from the Sound Up

[fromthesoundup]

And the crowd goes... silent?

Since the COVID-19 lockdown, stadiums around the world have gone silent. And while sports leagues are now reopening, it’s to a changed sonic environment devoid of the fans who give matches energy and personality. How can teams, leagues, venues and broadcasters bring the noise back without fans in the stands?

I wrote a thought piece with my Arup colleagues Lizzie Valmont, Matt Wilkinson and Brendan Smith about the challenges and opportunities of artificial crowd noise in the wake of COVID-19. Check it out here: https://www.stadia-magazine.com/fe

Photo courtesy Arup

[fromthesoundup]

La Musique Aux Enfants

Together with my colleagues Todd Brooks and Tateo Nakajima at Arup, I helped shape the acoustics of a new music program for preschoolers in Montreal. Read more about it here: https://www.lamusiqueauxenfants.org/

Photo by  Raphaël Thibodeau, courtesy the Orchestre Symphonique de Montréal

[fromthesoundup]

A Conversation with Leo Beranek

Leo Beranek, the preeminent acoustician of the 20th century, passed away on Oct. 10, 2016 at the age of 102.  In June this year, I interviewed Dr. Beranek with my friend Ross Urken, who published a profile of the man and his achievements in the science magazine Nautilus. 

The following is a transcript of the conversation Ross and I had with Dr. Beranek over lunch at his retirement home in Westwood, Massachusetts.

Beranek grew up in the small town of Solon, Iowa, where he repaired radios to pay his way through the local college. We asked him about his early experiences listening to and playing music.

What was the experience of listening to music like growing up? How did you listen to music? In a concert hall? On the radio?

Well now, certainly radio. But the radio was new. I was born in 1914, and radio was coming in to the United States in the '20s. And my family bought the first radio in 1924, and it was headsets. And there was one, only one station that I liked to listen to and it was called [indistinguishable] in Missouri, and they did music, so I did listen to music but it was headphones [laughs] and the headphones of that time were probably not very good quality. 

After my mother died we left the farm—I was on a farm 'til then—and went into the town school and the town school had a band. A sort of a marching band, you might say. And the band leader got me interested in learning the drums. And he could teach drums—he knew how to do it. And so I got a marching drum, which is one about so big around [gestures] and bounces on your knee, and I got to be pretty good with the marching drum. And then my father decided that since I was doing drums I should have a trap drum set for a dance band. So there was a fellow in the town there who was getting old and was not going to play the trap drums any more, so my father bought them from him for me. So then I practiced the trap drums in the basement of the high school—they let me have a room down there [laughs]. And then my father moved from this little town to a larger town and then I got involved with a local dance band—five local people.

And when I went to college, they had a symphony orchestra and I played in the symphony orchestra. And by then I was learning the timpani. And I went by train to Chicago occasionally and took a lesson from the timpani player in the Chicago Symphony. So I had some formal training. At least good enough that I could do fairly well. And when I came to Harvard in graduate school I played one year in the Harvard Radcliffe orchestra and I played timpani. Then I got too busy and stopped everything.

What kind of auditoriums did you play in?

Well in college they had a good performing center. No problems. And at Harvard they had the Saunders Theatre, which is a good theater. But then my first experience other than radio with a great orchestra was the Chicago Symphony. And you won't believe this, but every year they came out to our little college in Mount Vernon, Iowa called Cornell of Iowa and they came to the Spring Festival and played for three days. And the conductor of the Chicago Symphony at that time was called Frederic Stock. And it was of course one of the great symphonies of the United States, it was not a beginner symphony. But why did they come to that little town? Well, the president of the Union Pacific Railway told them that he would give them free transportation on sleeper cars and that since there was no hotel in the city he'd leave the sleeper cars there for three days, and the orchestra slept in the railway sleeper cars! And they came and played. Well now imagine the first time I heard a great orchestra in a good hall was the Chicago Symphony and boy, it sounded good.

In 1935, Beranek had the good fortune of meeting Glenn Browning, a pioneering radio technologist whose car had broken down on the Lincoln Highway in the town of Mount Vernon, Iowa. Beranek told Browning about his radio repair business and Browning encouraged him to apply to Harvard. Beranek did and got in. After obtaining his PhD in physics, he found himself in charge of a wartime defense lab where he helped improved fighter jet communications. 

One of the first things we did was to test whether people's hearing changed as you went up because we were dealing with unpressured airplanes, remember, so as you went up the pressure went down drastically, particularly at 30,000 feet. And now, does your hearing go bad? How much does your voice change?

 So we made tests at the Harvard Public School of Health, where they had a chamber where we could pump it down, and it was big enough to put people in, and we could then check their hearing as the pressure went down, and check the strength of their voice. Of course they had to have masks to get the oxygen, but they could take if off and talk for a bit, you see? And we could see what the voice did. And the voice got weaker but the hearing did not change. So that's the first important thing to know, is that the headsets that you used on the lower levels can be used at the higher levels, and they don't change with altitude, because your hearing doesn't change. So we got new headphones very quickly and [the ones for] all the armed services were not ones that changed with altitude. And they also had a nice, flat frequency response. 

And the microphones—we experimented with those also and improved them. And the microphones are inside the oxygen masks. And so our big contribution, early in the war, which is up to 1943, started being in all the airplanes, was improving the earphones and improving the microphones. And then the amplifiers—because the voice gets weaker—we put in an amplification that changed with the air pressure going down. It moved the amplification up, so we could keep the level more constant.

So it would detect the pressure level and automatically adjust?

Yeah, it's easy. A standard aeronometer. It's not complicated.

You were on the USS Canberra, and you wrote that the main danger with Kamikaze planes was the moment they come in undetected, and then they're spotted, and the response took too long?

First place, we got radars changed in a hurry. So instead of having you look at the things up here, and they were making plots by hand, they would see a thing come in, they'd draw it and then they'd go, 'Oh, we'll communicate those bearings to the gunnery.' Much too slow. So we had them bring the modern thing to horizontal. Put the tube that you're looking into horizontally, called Plan Position Projector, they called it. And now immediately when they'd see something they were plotting it immediately when they saw it—no time lost—and as soon as they saw there was enough to get a path, then by voice they would communicate to the gunnery and try to get that time down as much as you could. 

And so really changing the radar equipment was a big factor. And then making sure that they would communicate what they saw quickly to the gunnery, so we had to train the operators in the radar room in a language they could use to the gunnery that would get the maximum speed of getting the guns on target. So there were language problems we had to change. Well, we had this new equipment going into ships, and then the war was over. [Laughs.]

In 1948, Beranek, Richard Bolt and Robert Newman founded the acoustical consulting firm BBN. At the time, the field of concert hall design was a bit like the Wild West. 

When you were beginning your practice were acousticians seen as the authorities on how a concert hall should sound?

We knew nothing.

So who was seen as the authority on designing the shape of the concert hall?

Well, there was actually an acoustician in Illinois named [Floyd] Watson. And Watson, his theory was that you really wanted a dead room with the reverberation being only around the stage. And so he was involved in some strange halls [laughs]. But you see, to give you an idea, my first introduction to concert hall acoustics was 1950. They were going to build this new hall in Tel Aviv called the Mann Auditorium, and so the architect came over the United States and heard that—now, you see, we'd already started Bolt, Beranek and Newman, and he heard that BBN was a leading acoustics consulting firm. And at that time, there were only about 10 of us total, so he came to ask us if we'd be consultants on his concert hall there. And I said to him, 'Well, we don't really have much experience but nobody does.' At least, except for this old guy in Illinois. And so he said, 'OK,' so then I learned what I could. The Kleinhans Hall in Buffalo had been built. We had Boston Symphony Hall, and there was a Chicago hall. And...

And these were the only purpose-built halls for orchestral music at that time? 

Except for Carnegie. And then there was Carnegie. I guess that was pretty much it. So I then discovered that people like Symphony Hall the best of the group. But the architect knew—maybe it was [Serge] Koussevitzky, he knew a conductor who liked the hall in Buffalo, Kleinhans Hall. And so he convinced the architect that we should build a hall like Kleinhans Hall. Well now, there was a bunch of sort of misinformation on that hall. The hall there was designed by a Bell Labs engineer, and he—and I did this too in Tel Aviv—used [pioneering acoustician Wallace Clement] Sabine's data on audience absorption. Now Sabine got his audience absorption by putting students crowded together on benches in a hall in the physics department at Harvard. And these students crowded together absorbed less sound than if you put grown-up people in separate seats. So he go the audience absorption but then instead of publishing it on an area basis, which he also knew, he chose to talk about it in terms of people. But then, if we use those data, and then you spread the people out, you're going to find that the per-person absorption goes up if you [expose] the sides of them you see, whereas these students sitting together— and they're kids anyhow—they didn't absorb as much sound. So in Tel Aviv I also used the Sabine data—there was no other data. And the [Bell Labs engineer] used it and he predicted the reverberation time would be two seconds and it turned out to be 1.4, 1.5, and I was asked to go to Edmonton, Alberta in Canada, and they had asked for 2 seconds and it turned out to be 1.5. And they were also using Sabine data so they had too low a ceiling. You see, if his data would have been correct for the audience absorption that ceiling height would be OK.

There are a lot of dry halls at this time—Royal Festival Hall for example...

Same thing.

So the calculations were right, but it was this one missing piece of data?

Right. So it was Festival Hall, it turned out to be Tel Aviv, there was Edmonton, and there was Kleinhans, and Boston Symphony Hall, remember! Sabine said that the reverberation time there was going to be 2.3 seconds and it turned out to be 1.9. So even it missed, you see!

One thing I've never understood about Boston Symphony is why Sabine used the Neues Gewandhaus as the model. The Neue Gewandhaus had a fairly low reverberation time, didn’t it? Around 1.6 seconds?

Well he didn't know that. He decided to go to 2.3 and fortunately that was his calculation [laughs] because when it came down to 1.9 that's quite satisfactory, you see.

A happy accident?

A happy accident! [Laughs.]

Where did the 2.3 come from?

I don't know! It's what he predicted!

One of BBN’s first projects was an auditorium for a new university under construction in Caracas, Veneuela. The collaboration between architect Carlos Raúl Villanueva and artist Alexander Calder on the design of the space’s acoustical petals is well documented but less has been published about the role BBN played in the design process.

I’d like to ask you about a project you did early in your career—the Aula Magna in Caracas. What was it like working with Villanueva and Calder? 

Villanueva was a good architect. But the trouble was that the hall was already designed when we came into it. The exterior was even being poured, you might say. So they came to us and we said, 'Well, this is an awful shape. And maybe we gotta get some panels in there to see if we can counteract this bubble.' And so Bob Newman and I worked on panels and then Villanueva says, 'Well they can't look like that, you guys are designing square panels!' [Laughs.] 'We can't have that.' And he says, 'Why don't we get Alexander Calder interested?' So he contacted Alexander Calder and asked him if he would take on working with us to change these panels so they'd be interesting. So Bob Newman really worked a lot with Calder, and Calder never wrote with a pen, he always wrote with a brush. [Laughs.] I mean, one little thin tuft, not a broad brush, but a little tufted one you know, and he would write Bob Newman notes with the brush. Well then he and Newman sat down together and worked out these panels. And I was involved in the measurements both before and after and went down with Newman on all the trips, but it was sorta his project. And the hall of course is no Symphony Hall, but it's usable. [Laughs.]

So the shape and the location of the panels, those came from you initially?

Exactly. From Newman. Now what did you think of it?

Well I heard amplified music in there, so it's hard to judge. But I like to think of it as a really exemplary collaboration, because very often we work with an architect and we're calling the shots or they're calling the shots and it's difficult to build a rapport and to challenge each other. This was kind of Villanueva's M.O. for a lot of his work, to bring in artists and experts and the whole campus down there is just stunning, you're immersed in art and architecture and music.

Well I remember that the panels had just been painted and Villanueva had invited me to come down to the opening of the hall and so he and I came into the hall together and the first time he saw the painted panels, and he puts his hand and he says, 'Fantastico!' So he liked it! [Laughs.] 

In the late 1950s, Beranek worked with architect Eero Saarinen on renovations to the Tanglewood Music Shed, a covered outdoor auditorium that is the summer home of the Boston Symphony Orchestra. Conductors and critics raved about the improved acoustics and the project’s success helped establish Beranek’s reputation as the go-to concert hall acoustician in America. 

Why is Tanglewood—the Shed—so celebrated?

Well, there's a bunch of seats really in the front, not too much to the sides and not too far back, which sound very good. And all I can tell you is the RCA Victor people—were they the big recording people still back then? I think they were the ones. They came up and they liked it so, sitting in that area, that they said, 'Well we'd like to make recordings here!' And then I said, 'Well stop and think about it. The hall is open to outdoors and the humidity changes, and the rain comes and it's cold sometimes and birds come in and chirp and I don't think you want to make recordings here! [Laughs.] So they didn't.

It does sound unusual because recording engineers want as much control as possible, but it's pretty quiet out there, except for the natural sounds.

That's right. Have you been to Tanglewood?

I went there two years ago.

I see. Where did you sit there?

I sat in two places. I sat inside about halfway back...

More or less in the middle?

Yes. And then I joined my friends out on the lawn. And I have to say that I enjoyed being on the lawn more, but I think it's partially an issue of expectations. And that there was something so nice about being able to lie on the grass...

Oh yeah.

...with the sunshine and how informal it was and to listen to the music staring at the clouds, and I think the sound was better inside [laughs] but it was good enough that I kind of forgot about the acoustics. I'm not sure that's the answer you wanted to hear! 

Well I haven't been out there for several years now because at my age it gets harder to go. And my wife also finds that it's difficult for us as we get older to get out there. And so my last time there I sat in the boxes in front and it was pretty much in the center or off a little bit. It was so good, it sounded beautiful, it even surprised me that that box seat was so very good. 

You make it sound like it's not fully explainable, the good acoustics in Tanglewood, or do you think it's possible to define it with acoustical parameters?

Well, there are two things I know. One is that there's not too many [acoustical] clouds. And they are 50 percent open. And so you're letting the sound get up to the upper space and get a very rich reverberation. So the first thing, you get a richer reverberation. But then these panels bring in the early sound, and it's true we don't have lateral reflections but there are some reflections off of those panels to the sides. And that may be just enough to fool you [laughs]. I remember even Eugene Ormandy sitting with me and saying, 'Why does it sound so good?!' [Laughs.]

Of course there's other things that are not quite explainable. That orchestra is spread out fairly wide. And therefore you get sort of 'side reflections' from the orchestra itself.

Because the source width is so great?

Right. And I'm sure that makes a difference. But it also brings problems. If you get off to one side, the violins will sound stronger than the bass. And you get off to the other side, the bass becomes stronger than the violins. And I've experienced that. What you get in the middle balances nicely.

While working on Tanglewood, BBN was commissioned to consult on the design of Philharmonic Hall, a  concert hall for the New York Philharmonic planned as part of the Lincoln Center campus. The project began with a major survey of existing concert halls, which Beranek assembled into a book, Music, Acoustics & Architecture, now in its 3rd edition and regarded as a sort of bible of concert hall design in the acoustics profession. 

Can I ask you about your original survey as part of the Phiharmonic Hall work? Was that funded by the clients of that project?

It was funded by Lincoln Center, yes.

And I assume you were responsible for finding the halls to go listen to?

I did, and in the case of interviewing particular people, they would write a letter to them ahead of time and say that I was studying the acoustics, and would they talk with me? For example, [conductor Herbert] von Karajan. I spent three days with him. But he did it because he was told by Lincoln Center that this was important. And so he became a very good friend of mine. And we spent three days together.

And what was the process like when you went to meet with a conductor? Because I believe you asked each of them to rank order their favorite concert halls?

I did, right. And I would ask them about some halls that they didn't think about. And said, 'Have you played in this hall?' 'Yes.' 'What did you think about it?' 'Oh it's not so good.' Y'know. That sort of thing.

And were they answering from the perspective of the conductor's podium or the audience? Did that matter to you when you did your survey?

Well, we would ask for their opinion on both. Generally, these conductors tried to go to a concert too and hear the hall. For example, Eugene Ormandy was very careful to say, 'Well I sat here and I sat there and on the stage I had these problems,' and he discussed the whole thing, you see? And he did not like the Concertgebouw. Even though most conductors said it was one of the great halls of the world!

The Concertgebouw's a really interesting case though. Compared to Vienna [Musikvereinsaal], where the consistency of the acoustics is very different between the two halls. My guess is that in Vienna, the sound you get at the podium is similar to what you get in the audience, whereas when I was at the Concertgebouw I sat about two—thirds of the way back and then I moved up front and it was dramatically different.

Oh, dramatically different!

It was terrible up front!

Ormandy said that, 'First of all this stage side has a steep ramp to it, and they have audience on both sides of the orchestra,' and he said that the overhead sound didn't work very well, and he got no sound on the stage from the sides. It all came from overhead. And he didn't like the hall. But then other conductors said, 'It's one of the great halls. We enjoy it.' Now you must remember that part of the reason that these three halls [Grosser Musikvereinsaal, Concertgebouw and Boston Symphony Hall] get these fine reputations is that you've never heard bad music in it. You've got great orchestras. And kept feeling there's something about hearing great music... [Laughs heartily.]

It raises an interesting question for the designer, though, because you could have a great-sounding room—the physics of it—but a room that no good orchestra has ever played in. So did you try to factor in that kind of a bias, you know, how good the orchestras were, how well-known certain halls were, in your survey?

Well of the 58 halls in the paper I published in [Acta Acoustica united with Acoustica Vol 89], and the first 20 halls were the ones that I was able to talk about the most with the conductors and the music critics. And then there was a group of halls that was so bad [laughs] that the bottom group was easy to put there. Then if you look at my study, the middle group, I said that they just seemed to be all about the same, not great, not bad. And that middle group is kind of indeterminate.

Beranek correlated his survey subjects’ preferences to architectural and physical measurements in the concert halls they mentioned to establish ideal parameters for concert hall acoustics, some of which—notably a reverberation time of 2.0 seconds—remain commonly accepted design targets today.

In your survey, you found that the optimum reverberation time for a concert hall was, I think, 2.0 seconds exactly. Going into that survey, did you intuit that that would be the value that came out?

Well, my design plan in Tel Aviv was 2 seconds.

But that was prior to the survey, no?

Yes. And partly that's because — now let me see... I'm not sure whether I knew Boston Symphony then or not. [Long pause.] But... [long pause.] But somehow my design number was 2 seconds. I can't remember why. [Laughs.]

There was some debate prior to your survey about how dry or live a room should be. For example, Floyd Watson...

Floyd Watson, he's the one I was speaking of, the old man...

Where did that idea of a really dry, outdoor sound come from as an ideal, because none of the great halls of Europe are that dry.

I can't answer that. That was his idea! And one place it showed up was this hall in Washington D.C. that they called the Daughters of the American Revolution or something but it turned out they had an absorbing back and just the live area around the stage. And that hall has always been hated too [laughs].

Have there been any halls you've attended that have great acoustics but don't conform to the parameters that you established in the survey? Have there been any big surprises that are hard to explain?

Well the most successful non-shoebox hall is Berlin. The Philharmonie. Well, [acoustician Lothar] Cremer was very scared of that hall. He thought it was going to be a flop. So he convinced the orchestra that they should engage a second hall, even if they were not going to play in it. And if the objections were too great, they could go to the second hall. And they did that! And furthermore, he tried to scare Scharoun, the architect, into not doing this hall. And So he asked me to come over and meet with him and Scharoun, and I argued that they should make it like Symphony Hall. And Scharoun paid no attention to either of us [laughs].

When you say it's successful, is that your own opinion or is this going off the mass of critical reviews?

Well, it depends on where you sit. My opinion is that there's about a quarter of that hall, where you're in front... Now remember, half the audience is seated around the orchestra, so if you're in front and don't go too far back, the sound is quite good. And the statement that [acoustician] Müller makes today is that the aficionados know where to sit and the tourists fill the rest of the hall!

Are there some halls that don't have good reputations that you really like? Or you think are kind of unsung great halls of the world?

I would say that most of the halls that the architects like, I liked. Oh, let's look at this dessert menu.

[We look at dessert menu.]

Of course, the best dessert here is apple pie a la mode. And the frozen yogurt is another one where you get less calories, that's usually pretty good. [To server:] I'll have the frozen yogurt.

Despite all of the research that went into the design of Philharmonic Hall, it was panned as an acoustical disaster. In 1976 the entire auditorium was demolished and rebuilt with acoustician Cyril Harris brought in to consult. Beranek was not responsible for many of the design decisions that doomed the hall’s acoustics but regardless his reputation as a concert hall designer was severely damaged. Philharmonic Hall’s failure has been pinned squarely on the building committee’s decision to add seats by bowing the side walls of the auditorium, but Beranek reflected on some other possible reasons for the hall’s shortcomings, including some decisions he made. 

Of course, my big problem came with Philharmonic Hall in New York, where the ceiling reflection was overdone. As you saw in my autobiography, it was a mess. They didn’t build the hall we designed, because we were trying to design another Boston Symphony there. And in fact, that was in the newspaper with a picture calling it, ‘Final Design.’ The picture was on the front page of the New York Times, and they didn’t build it.

Why didn’t the architects communicate with you?

Well, they communicated with me. But it was, ‘Do it their way, or die.’ What I should have done was quit. If I’d have resigned, that would have been my best answer. I wouldn’t have gotten blackened so.

Does it still frustrate you?

Well, it’s a long time ago. And I decided from the beginning not to let it bother me, just say, ‘It’s there. I can’t change it.’

Are you involved in current plans to overhaul Geffen Hall?

I have not tried to push myself into it. The acoustical man [Paul Scarborough]  just communicated with me recently and said he wants to come up and see me. So that will be my contact to it. But again, I’m sure the architects are going to have a lot to say. You see, one problem we had with Philharmonic Hall was the architect was not a good man. He was really a weak person. And he got pushed around by everybody. And let me tell you the thing I don’t think I put in the book: I wanted some irregularities on the walls, and they ended up being absolutely smooth. Now the architect fought with me, and he told them we want the irregularities on the walls. And the building committee says, ‘O.K., You’re through. We’re hiring an interior decorator.’ The hall’s interior was done by an interior decorator, not an acoustician, not an architect.

Were you able to communicate with the interior decorator?

I never met him. I should have resigned, you see, which I didn’t do. We were consultants at the time to the [Metropolitan] Opera House, and I didn’t want to lose that job. So if I quit one, that would make me quit both of them. After the trouble came, then they did sort of disregard me at the Opera House. They paid my fees, they took my report, and they really built pretty much what I had but gave me no credit.

Did you use Sabine's [faulty] audience absorption data when you were working on Philharmonic Hall?

No, no, no. I had good data for that. So the reverberation times there were always high—no problem with that.

So you were aiming for 2 seconds on Philharmonic Hall?

You see, the big complaint on Philharmonic Hall as it exists today is that the bass is not strong enough. And if you read the reviews, they talked about the bass not being strong enough. And in the case of what's there now, the architect working with Cyril Harris lined it with wood, and wood absorbs bass. So the bass today is missing because of wood. The bass in my case was a case of not... if we'd put the front of Boston Symphony Hall there, we'd have had bass—but the trouble is the sound could go around back. We had too much openness.

In the orchestra enclosure?

The orchestra enclosure was open, not solid. So the sound could go around back and the bass got absorbed there. The high frequencies went out OK.

So there was a kind of backstage area?

Yeah. I don't know what that was used for [laughs], that space except they could go in and out through there because they had separate rooms for the orchestra to tune. They didn't have to go around, just around the stage. But then later, I found that that was where the absorption was coming from. There was some absorption in the pipe organ and that also took some bass out. But the big absorption was around the back. And if I'd known enough and forced the architect, if that was possible [laughs] to put in what's in Symphony Hall afterwards to correct it, we'd probably have recovered the bass. But then they hired other consultants and I was out of it.

If you were to do it all over again do you think you would go with the same design? Or do you think, after moving on in your career, you would have edited or altered that original design?

Well the only thing I would have changed was not make the hall quite as wide as it is. It's a wider hall than I would like it. I would like it narrower. Because when you get wider, then these reflections come in later and you don't get the full effect of them. So it would be better to have the hall a little narrower. But then that's going to restrict the audience size and that's what got us in trouble to start with! We wanted to keep the audience down to 2400 and I even wrote a paper that went into the Lincoln Center's own publication arguing how strong I felt about 2400 seats. Well then the building committee came in and says, 'It's going to be 2700.' And that's when the big changes came. They had to pack in 2700 and that meant the balconies started to be horizontal, had to come up like this, so you get bigger area in the balconies, you get more people in. And everything changed then.

After the disastrous experience of Philharmonic Hall, Beranek turned his attention away from concert hall acoustics and towards other projects at BBN, which had expanded from its initial acoustic consulting practice into other areas of technology and communications. Among these prjoects was ARPANET, the immediate forerunner of the Internet. 

ARPANET [laughs] is so different. You see, let's get the reason why the ARPANET was financed. The ARPA was a  part of the Department of Defense, where they put money to do unusual things. They really told them, 'You can spend big money doing some unusual things.' So at that time, we were prominent in the beginnings of time sharing, where multiple people could use one computer without these people knowing that each other was using it. It's called time sharing. And our company was right up front in that. And if fact, the first public demonstration of time share—our company made it. So we were very much in this. 

Well then ARPA decided that what they'd do is put a big computer in each of the big universities and they would time share them so that all the people in the university could use one big computer and just have terminals out. And that resulted then in these different universities and there were 19 of the universities that put these expensive computers in, and I'm sorry, not all universities. Some of them were government installations. But there were 19 total. And then somebody said, 'Well why don't we hook these things together?' And then the smaller universities will not need to get a big computer because they can hook into this communication line with just a keyboard, so to speak. And then they can ask for time on these big ones. And get permission to use Harvard's computer for maybe an hour after midnight, and MIT's for an hour. Or UCLA's for an hour, so that the smaller universities could use the big universities' computers but if we hook them all together then they can have a choice of 19 big computers. So they then said, 'Well, ok we'll hook these together — that's never been done before — so why don't we finance somebody to figure out how to hook 'em together.' 

And they sent out proposals to, I don't know, 60 companies or so, and 30 responded and told how they would do this, and it turned out that our company and Raytheon had the best ideas on how to hook together these with a network. And finally when they got down to studying it they said that they thought we would do a better job than Raytheon. So we got the job of hooking the 19 computers together. And that was the ARPANET. Then when the ARPANET got so — as it grew, other people wanted to hook in, even England hooked in, and when it got up to about 500 people on it — 500 users — they decided to split it in two and make two networks, and then coupled them together with the TCP/IP protocol, which is not Bolt, Beranek and Newman's, and that was the Internet. And from then on, it grew like fury. [Laughs.] But the PC came in, remember that was a big push. Everybody got into it then.

During his time away from concert hall acoustics, other acousticians began to challenge some of the measures and targets Beranek had derived in his survey as well as propose new ones. 

Did it come as a surprise to you when Harold Marshall and Mike Barron published their articles on lateral reflections? Because it's something that is missing from your initial survey.

If you read my last paper, the last paragraph talks to this. But you see, the problem with his design is that they are taking too much of the early energy and throwing it back on the audience. So you don't have much energy going into reverberation. And so the reverberation lacks intensity, it's quieter. And I don't like that.

The acoustician Eckhardt Kahle recently tried to quantify the ratio of early to late energy. That was part of the design for the new Philharmonie de Paris. The acoustical consultants for Paris claimed that their design strategy was to reflect a lot of early energy back and then add reverb chambers to boost the reverberation time. But it doesn't really work because it decouples the early sound and the reverberation, so you get strong direct sound because you're close to the orchestra, and you get reflections from the side walls and reflectors, and then there's nothing.

Well it's partly a matter of energy, you remember? That you take so much energy away from the reverberation. Now, there's another problem that people are not aware of. And that is that in most of these surround hall — you take Disney [Concert Hall], and you take — well, this new hall in Paris — those two examples. They're using heavily upholstered seats. So much so that whether the audience is in there or not, the reverberation is the same. Now what does that do? You find that even when the audience is there in  heavily upholstered seats, the audience absorbs more sound than if they're on seats like in Symphony Hall, where the absorption is very little in the chairs. And the difference is then that you're not getting enough energy into the reverberant sound.

It basically goes to waste because it's not reaching people's ears. It's just the chairs sucking it up.

Chairs sucking it up. So now, if I go to three principal halls where they have these heavily absorbing chairs — one is in Japan [possibly Suntory Hall], one is Disney, and one is Paris, I've had now audiences say, 'These halls are pretty good with Mahler — they've got full orchestra, loud. But when you get a quiet group in there, they're too quiet. The hall doesn't have the strength it should.' And that's due to the heavily upholstered seats.

Have you been to Snape Maltings in the United Kingdom?

No. 

This is the first project designed by Arup. A concert hall by Derek Sugden. And the seats there are wicker. So they absorb no sound whatsoever. And it's a nightmare for rehearsing in there... 

Oh yeah, it would be.

...but when it's full to capacity, it sounds marvelous in there, and the entire space is a brick floor, brick walls, heavy timber ceiling, and you really sense that some of the sound energy hitting that floor is not absorbed, that it's a very enveloping kind of sound. It’s a kind of hard sell to an orchestra to have such a big difference between a rehearsal condition and a performance condition.

Well, of course [acoustician Russell] Johson tried to take that into account in the one over in Switzerland.

KKL Lucerne?

Lucerne. And he had the curtains you could pull out. And that helps overcome that argument. Because you pull the curtains out during rehearsal.

Russell Johnson was an architect who worked with Beranek at BBN on the design of Philharmonic Hall and later founded his own firm, Artec. Johnson was more successful than his mentor at winning concert hall work. He designed some of the most highly-regarded concert halls of the late 20th-century, many of them incorporating his signature reverberation chambers.

How did Russ Johnson start working at BBN? Because he was an architect.

I know, but the head of our architectural acoustics division after it started growing—I was spending more of my time with the ARPANET kind of people, and less time with acoustical people—Newman and Cavanaugh took over. And they ran the architectural acoustics. And they hired him. Now why I don't know! [Laughs.] Well, Russell was a problem also. Because he was not very good on keeping books or getting his charges in for travel and all the things that you expect an employee to take care of he did not do.

Did you work together much? Or at that point were you kind of working in separate departments.

No, but he worked with me on Philharmonic Hall. By then, he'd been working in architectural acoustics quite a while. So he had ideas. And we worked together fairly well. But nothing we could do to change the changes or prevent the changes that took place.

Did you have slightly different ideas about acoustics or about how rooms should sound?

Of course his idea even when we were working together on Philharmonic Hall even, he said, 'Why don't we have some chambers on the side that we could open and close?' And I said, 'This is too expensive, too much trouble, we can't do it.' And so I prevented them from coming in to Philharmonic Hall. But then he got them into other halls. [Laughs.] But the chamber idea hasn't been terribly successful.

It may be a problem of where the energy goes and that the chambers begin to decouple the response of the room, and it's maybe not quite as even a response. I went to Symphony Hall in Birmingham recently and the audience was very impressed when the reverberation chamber doors moved at intermission. It was very dramatic when they opened and closed. So it adds to the spectacle.

You heard the difference?

I did. But, you know, I think the intention was simply to change the reverberation time without anything else changing, and of course it changes the spatial balance...

Yes, it does.

... and in Birmingham the reverberation chambers are above the stage and make the sound sound more frontal and there's a bit of image uplift and I don't know, not all coupled sounds sound alike, I guess. It's not going to sound like the Concertgebouw, this rich, spatially broad, well—integrated sound, somehow.

Well I never saw the two comparisons. Or heard the two comparisons. I was there when they had it where they liked it. And it was fairly good, the Birmingham Hall.

I think another reason I'm not a huge fan of it is... It's that it sounds a lot like the Musikvereinsaal in Vienna, and to be honest—and this is off the record—I don't particularly like the sound in Vienna.

You're right—Boston is better! And von Karajan and I talked a lot about this. And he liked Boston better.

And what did he have to say about that?

First of all, the Musikvereinsaal gets very loud. It's very intense noise. Sound, not noise, but sound. And as you go back in there the reflections off the side walls change. It's not uniform reflections. So it depends on where you sit and what you hear. It's not uniform.

How does the sound change?

Well [laughs], it changes when the reflections from the side walls change. That's what you hear.

They become relatively stronger...

... or weaker. And that's particularly at the higher frequency ranges, you see?

In 1972, Beranek’s book Music, Acoustics and Architecture was translated into Japanese. Japanese acoustician Takayuki Hidaka read it and invited Beranek to collaborate on a number of research and design projects in Japan, which culminated with the design of Tokyo Opera City in the late ‘80s. Tokyo Opera City gave Beranek the chance to salvage his reputation as a concert hall designer three decades after the disastrous opening of Philharmonic Hall. 

What did you learn from the experience of designing the opera house and concert hall at Tokyo Opera City? 

You're working with an architect, and in this case the architect wanted to do everything he could with good acoustics but he still wanted his design, so we had to work with him carefully. Now the [Tokyo Opera City] Opera House — he did not want to go to the old circular opera house. But he wanted to have a sound that was uniform through the hall and also that the singers on stage could move around and their voice would [wouldn't?] go up and down. So in the case of the Opera House, we developed a sort of horn idea, and it's built into the side walls and into the canopy, it's sort of a horn thing, that distributes the sound quite uniformly over the hall. It's the best I've ever done. And in testing we had singers walk around the stage and keep singing while they were walking. And the sound did not change in amplitude [while listening] in the audience. So we achieved our goals there. So even though it's different, it's successful.

Would you apply that technique if you were to design a hall for symphonic music or is it just for opera?

Well, you must remember that the reverberation time in an opera house is lower than the concert hall. So when that sound is as live as, say, Symphony Hall, it's a quieter hall. But you want to hear the singers' voices more clearly and if you go to Symphony Hall with opera singers, their voices are not as clear as they are in a real opera house. Now the concert hall—we tried to copy the principles of the shoebox hall all we could, but the architect wanted a different ceiling. He wanted this pyramid up there. And that created a terrific problem, because now see the stage is here [points] and this back wall comes down [points] and this could create an echo back to the orchestra and to the people in front. It would be unbelievable. And so the big effort that we made with the architect was to get rid of that echo. And we finally went to these shredder kind of diffusers. Sound comes up to them and gets thrown to the sides. And that's the way we left it finally. So half the ceiling is covered with these shredder diffusers.

I get the sense that Opera City was a bit of a redemption for you. Is that correct?

Well, the New York Times is the one that confirmed this. They ran this big write up on those two halls in Japan, and started from the front page. And on the front page they had the architect's picture and underneath it it says, 'Acoustics miracle.' And then inside they even had a box which said that this was my... uh... what's the word I want?

Comeback?

Comeback, right. And they said there had been so much negative talk about Philharmonic Hall and this was just reversing it. So the New York Times tried. I certainly am happy with what happened in Japan. Very much so. I hate to claim anything because you're always working with architects who want to do something different. They don't want to make another shoebox hall. And Yanagisawa wanted this pyramid thing on top, which was completely different. Fortunately, we could handle that. I'm not sure we could handle every architect's idea! [Laughs.] 

Geffen Hall, the current incarnation of Philharmonic Hall, is slated to be gutted for a second time, with English industrial designer and architect Thomas Heatherwick leading the design team and Akustiks providing acoustic consulting. 

You say someone from Akustiks is coming to meet you at some point to discuss David Geffen Hall. He obviously wants your knowledge base.

Oh, I dunno. Or else he just wants to talk [laughs].

Would you be game to, say, consult on a project like that?

No, no, not at my age. No more consulting!

What would you tell someone designing it, not so much about the acoustics per se but what advice would you give them for managing the task of working with an architect, of knowing when to threaten to quit, basically? Maybe there are some lessons beyond the acoustics to ensure the success?

Well, of course I would be more definite today in who I'm consulting for and that if the building committee is going to be involved, that I have also got to have communication with the building committee. You see, the architects Harrison and Abramovitz said, 'Absolutely you must never talk to anyone on the building committee!' So they prevented us from talking to them. But it was the building committee that ended up getting the interior decorator. They were the ones that one should be influencing, but we had no contact with them. So my feeling would be that somehow if you could tie down at the beginning who you're communicating with and how much power the building committee is going to have over the architect, and if they're going to have to agree, we're going to have to talk with all of them. That would probably be my approach.

Image Credits

Aula Magna: http://delacasaalaciudad.blogspot.com/2014_07_25_archive.html

Tanglewood Music Shed Sketch:  Reproduced from Music, Acoustics & Architecture, 1st edition. 

Postcard of Philharmonic Hall: collection of author

The Philharmonic Hall Listening Panel: Reproduced from Music, Acoustics & Architecture, 1st edition.

Tokyo Opera City Concert Hall:  www.operacity.jp

[fromthesoundup]

Mysterious missing reflections at De Bijloke

I arrived at De Bijloke, a concert hall housed within a medieval hospital in Ghent, with high hopes for the acoustics. The hall is particularly narrow, and narrowness is good, because it means strong side wall reflections will arrive at listeners' ears soon after the direct sound. Strong, early-arriving side reflections make the sound image louder, clearer and broader, and can make the musicians sound closer than they look, contributing to a perception of intimacy. To be precise, De Bijloke is 3 meters narrower than the Grosser Musikvereinsaal, the benchmark by which all rectangular halls are measured, so I imagined the sound might be even louder, clearer, broader and more intimate than in that most acoustically-acclaimed of halls.

Before I deliver my verdict, a bit of history. De Bijloke was constructed in the 13th century, when Ghent thrived as a major cloth manufacturing center, to replace the older (and likely overcrowded) Maria Hospital of the Cistercian order of nuns. Erecting its massive timber truss ceiling apparently required that a "whole forest" of oak trees in southern Belgium be felled. After the French Revolution, De Bijloke became a civilian hospital, and it remained in operation until the early 20th century. After lying vacant for a number of decades, the building was in 1999 repurposed as a concert hall.

Taking my seat about two thirds of the way back just to the right of center, I strained my ears to hear the woodwinds warming up over the din of the audience. "Sound is a little distant," I noted, but hoped that it was simply because of the chatter. But the sound didn't improve once the concert began. The program began with Schumann's piano concerto in a minor. The sound was reasonably clear and warm, but it lacked intimacy. I felt removed from the music, disengaged, on the outside. At intermission, I moved up several rows to an empty seat about halfway back. The program continued with Bruckner's 7th symphony and despite the increased orchestral forces and my new position closer to the stage, the sound remained far away, over there. I could hear some sound energy coming from above but almost none coming from the sides. As a result, the sound image was compressed, constrained, unable to grow or swell or bloom. If I had walked into the concert hall blindfolded, I would have guessed I was sitting in a much wider room with far more than its 975 seats (Geffen Hall, formerly known as Avery Fisher Hall, came to mind).

I felt disappointed not because the acoustics were poor but because I had failed to predict as much. How could I have been so far off the mark?

According to a 2003 article in Sound & Communications Magazine, De Bijloke's weak, distant sound impression can be partly blamed on the room's timber rafters, shown below, which "act as a huge baffle and soak up any potential reverberation." 

The article profiles a survey done by Artec Consultants soon after the hall's opening in which it was found that the room had a reverberation time of only 1.3 seconds, far below the recommended 2.0 seconds for Romantic orchestral music. Because historic preservation laws precluded any invasive changes to the building, Artec recommended enlivening the room electronically, and the management installed a LARES elecro-acoustic enhancement system made up of 90 loudspeakers on the ceiling beams (look closely and you will see a few in the photo) and under the floor.

During the concert I attended, the sound did not strike me as being unusually dry, so the system must have been turned on. But what about the weak lateral sound? The smooth, massive stone walls were clearly not absorbing sound like the ceiling rafters. Scanning the room for clues, I noticed something odd up at the front. The portable reflector panels standing upright at the edge of the stage weren't parallel to the adjacent side wall.

The side walls, I could now see, were not vertical! They leaned outwards by a few degrees, pushed over hundreds of years by the lateral force of the dense, massive ceiling trusses. A walk around the outside of the building confirmed the finding. Here I am, standing upright in the modern corridor that surrounds the historic structure. Observe the angle of the buttresses compared to that of the new mullions to the right.

A little angle goes a long way acoustically. A vertical wall will send a strong side reflection to everyone in the audience if there is a reasonably high stage and/or a reasonably steep rake.

A slight angle, however, will reflect energy upwards, over the heads of the audience.

For sound to reflect off an angled side wall and reach a good portion of the audience, the stage must be very high or the rake must be very steep. At De Bijloke, the stage is only about a meter high and the rake is very shallow. A steeper rake might have facilitated strong, early lateral reflections audible but it would have also reduced the room's acoustical volume, further driving down the reverberation time—a damned if you do, damned if you don't scenario.

It appears that the consultants at Artec and LARES were aware of the lack of lateral energy in the room but were unable to do much about it. The article in Sound & Communications explains:

The hall's management was concerned about the location, number and visibility of the speakers, preferring that they not be seen at all... The overhead speakers were not so much the issue - they could be painted and tucked on the stage side of the ceiling beams to hide them from the audience. But, because no speakers could be placed on the walls, this meant finding a different solution for the lower lateral components.

If De Bijloke’s management had opted for speakers on the walls, the angled side walls might have been acoustically straightened, providing strong lateral reflections to the audience and giving the sound the presence and intimacy it so badly lacks. Instead, the “different solution” was to locate speakers in the air plenum underneath the raked floor, which in my experience did not make up for the missing side wall reflections. 

I suppose there are two design lessons to be learned from the case of De Bijloke. First, make sure your side walls are straight. Second, make sure that your side walls will be straight for the next 800 years, because who knows, people may still be listening to Bruckner in 2816.

Program Notes

De Bijloke March 12, 2016

DeFilharmonie Edo de Waart, conductor Jan Lisiecki, piano

Robert Schumann (1810-1856) Piano Concerto in a minor, op. 54

Anton Bruckner (1824-1896) Symphony no. 7 in E Major (version Nowak, 1954/2003)

[fromthesoundup]

What Does Gray Sound Like?

Occasionally, someone asks me how the color of a material affects its acoustical  performance. It doesn't, physically speaking, but color and light can influence our psychological perception of sound. In my article on the Grosser Musikvereinsaal, I hypothesized that its great acoustical reputation may be in due in part to the room's golden appearance. There is also some scientific evidence that color affects auditory perception—Hugo Fastl, a professor at Munich Technical University, found that participants in a controlled lab experiment found a red train to be louder than white, blue and green trains, in that order, when played the same sound.

I visited the Concertgebouw in Bruges, a recently-constructed 1290-seat concert hall designed by architects Robbrect and Daem with Arup as acoustical consultants, to listen to gray. When I first saw a photograph of the concert hall auditorium, I assumed it had been converted into black and white. It was not, however. It was a color photograph of a black and white auditorium.

If the Musikverein's golden sound equates to warmth and brilliance, then the Concertgebouw in Bruges should sound cold, dry, flat, lifeless. None of which are qualities most people would associate with good acoustics.

Taking my seat in the front row of the second balcony, the lights went down, the conductor walked out and as the band broke into Gluck's Dance of the Blessed Spirits from the opera Orfeo et Euridice, I found myself immersed in one of the largest, warmest, most embracing orchestral sounds I've heard.

If the auditorium had had an objectively low reverberation time or weak early reflections, I think the gray color would have made the music sound more dry, distant and lifeless by association. But what I experienced was contrast—warm and alive, the orchestra's sonic color shone more vividly against a neutral background.

I attribute the Concertgebouw's acoustical warmth in part to the wooden slats that cover many of the surfaces in the room. The slats vary a bit in scale but not much: they range between a half inch and two inches in width and depth. At this scale, they diffuse sound waves at high frequencies, taking the top "edge" off the sound.

It is perhaps an oversimplification to claim that I experienced complete contrast between visual grayness and auditory color. In fact, the first thing I noticed when I entered the auditorium was that some of the slats were not in fact gray but were painted green or blue. Not many, but the few lines of color immediately attracted my attention. They do not photograph well, appearing almost like chromatic lens aberrations, but in person, they really stand out. The second thing I noticed was people. Clothing, faces, musical instruments all popped against the gray walls and black seats as shown below.

The gray itself changed character throughout the evening. With the house lights up before the performance, it could appear almost white in contrast to the black flooring and seats. When the house lights went down, the gray reflected very little light from the stage and merged with the black, plunging the entire audience into shadow.

Onstage, the gray orchestra shell screens took on whichever color was projected onto them by uplights arranged around the perimeter. And, as would seem appropriate for a program made up of lots of little morceaux, there were lots of colors. Probably too many. But when the stage went blood red during an excerpt from Prokofiev's ballet Romeo and Juliet, the effect was powerful— visually, and indirectly, aurally.

At the Bruges Concertgebouw, gray acts as a sort of perceptual infrastructure—while it is initially disorienting to enter a concert hall that appears to be drained entirely of color, it soon becomes a background for strong, dynamic colors made by people, lights and music.

Program Notes

Concertgebouw Bruges March 10, 2016

Symfonieorkest Vlaanderen Dirk Brossé, conductor Jo Lemaire and Hans Peter Janssens, soloists 

Christoph Willibald Gluck (1714-1787) Dance of the Blessed Spirits, from Orfeo & Euridice

Sergei Prokofiev (1891-1953) Juliet as a Young Girl, from Romeo and Juliet Montagues and Capulets, from Romeo and Juliet 

Dirk Brossé (1960 —) Für Elise @ the movies

Gabriel Yared (1949 —) Camille Claudel Coco & Igor

Igor Stravinsky (1882-1971) Four Norwegian Moods

Leonard Bernstein (1918-1990) Maria, from West Side Story

Queen Who Wants to Live Forever

Marguerite Monnot (1903-1961) Hymne à l'amour

Louis Guglielmi (1916-1991) / Edith Piaf (1915-1963) La vie en rose

Michel Vaucaire (1904-1980) / Charles Dumont (1929 —) Non, rien de rien

Charles Aznavour (1924—) La Bohème Plus bleu que tes yeux

Dirk Brossé (1960 —) / Jo Lemaire (1956 —) Le jasmin et la rose

[fromthesoundup]

Victorian Splendor at Leeds Town Hall

I wouldn’t have visited Leeds Town Hall were it not for the quirks of the privatized UK rail system. It turned out to be far cheaper to book a ticket with one rail company from Saxmundam (the nearest station to Snape) to Leeds and a ticket from Leeds to Manchester with another company than traveling directly from my origin to my destination. I should be thankful, because Leeds Town Hall turned out to have better acoustics than practically any concert hall I’ve been to (at least from my seat two-thirds of the way back just to the right of center).

The outstanding acoustics at Leeds Town Hall came as a surprise. Taking my seat and gazing up at the vaulted ceiling, I imagined a cavernous, reverberant, sound. When the Leeds University Chamber Choir filed out onto the stage platform and began to sing Antonio Lotti's Crucifixus, an eight-part Italian Baroque motet, I did a double take. The sound was focused, dry and crystal clear. Where was the reverberation? In my notebook, I jotted down, 'Almost like an outdoor sound.' This was perhaps an overstatement—there was certainly enough energy in the room to support the singers, to help them blend together, to allow their voices to broaden and bloom in the crescendos—but it accurately reflects the difference between my visual expectation and aural experience.

The chamber choir filed offstage and their place was taken by the Leeds University Symphonic Wind Ensemble, who played a contemporary, tonal, sacred hotchpotch of a piece—drum solos here, Bach chorales there, and the whole ensemble breaking out into song at the end. Not exactly my cup of tea, but the acoustics continued to impress. The sound was warm, large and loud without being overwhelming. The balance between sections was a little lacking but that was because the ensemble was seated mostly on the flat stage extension with only a few players on the rake.

Going into intermission, I couldn't bring myself to move to another chair. The sound from where I was sitting was just too good, so I decided to indulge myself, forsake my research impulses and remain in place. I now regret it somewhat because it is quite possible that I found a small sweet spot in the auditorium, and as I wrote in my post on the Concertgebouw, a sweet spot can be wholly unrepresentative of a concert hall's acoustical landscape. Could it be that I am lauding a sonic environment few others will hear?

After the intermission, the Leeds University Symphony Orchestra and Choir assembled to play Mahler's Symphony No. 2. The performers filled the entire stage extension and the better part of the raked choir risers, shown below, and there were easily twice as many performers as audience members. 

I suppose the orchestra, made up mostly of amateur student musicians, should be applauded for its audacity in taking on such a massive work. The performance, in other words, was not great, but by the end, I was in tears—my first cry of this listening tour—and for that I have to give most of the credit to the acoustics. 

As when the wind ensemble played, the balance was not always perfect due to the lack of risers at the back of the stage extension, but otherwise, I can't imagine a better environment in which to listen to Mahler. My colleague at Arup Tateo Nakajima recently pointed out to me that Mahler poses an acoustical challenge because despite the large orchestral forces, many passages are chamber-scaled, requiring conversations between individual instruments often situated across the stage from each other. The vastness and intimacy are difficult to accommodate within one acoustical room response. From my seat at Leeds Town  Hall, quiet, chamber passages were present, clear and intimate, just as when the chamber choir first performed, and tutti passage were rich, punchy and powerful. The combination of warmth and clarity allows instruments to rapidly change character: one contrast the acoustics really brought out was near the end of the final movement, when the trombones play a soothing four-part chorale and then, after a timpani drumroll, roar back into life in terrifying unison.

Walking away from the concert slightly dazed, I tried to make sense of what I had just heard. What was architecturally responsible for the outstanding acoustics? I began by looking at the hall's history.

Leeds Town  Hall is one of many monumental town halls constructed in the north of England during the Victorian era. According to historian Tristram Hunt, The burgeoning industrial cities of Yorkshire and Lancashire had gained a reputation for being cultural wastelands, and local elites sought to rectify that by commissioning great halls that could host concerts as well as balls, banquets, bazaars, exhibitions and political meetings. After its smaller neighbor Bradford built a town hall, Doctor John Heaton led the effort to build one in Leeds, declaring:

If a noble municipal palace that might fairly vie with some of the best town halls  of the continent, were to be erected in the middle of their hitherto squalid and unbeautiful town, it will become a practical admonition to the populous of beauty and art, and in course of time, men would learn to live up to it.

Moral reform was central to the project of town hall building, and, according to historian Rachel Milestone, a large performance space was expected to tempt working-class music-lovers away from taverns, the principal sites of music-making in the early 1800s.

The 1852 competition to design Leeds Town Hall was won by architect Cuthbert Broderick, who modeled his Great Hall after that of Liverpool's St. George's Hall, shown below courtesy Dave Wood. (Copied is perhaps the more accurate term, as the two rooms' dimensions are nearly identical). 

Harvey Lonsdale Elmes, the designer of St. George's Hall, is believed to have modeled his room not after an existing space for music but after the frigidarium at the Roman baths of Caracalla, shown below in an 1899 reconstruction.

The historical chain of design inspiration does not yield much evidence for the great acoustics at Leeds Town Hall. A formal analysis, however, reveals similarities, coincidental though they may be, to highly-regarded concert halls that would be built some decades after the completion of Leeds Town  Hall. First, the footprint of the Great Hall at Leeds, shown below, is nearly the same as that of the Grosser Musikvereinsaal in Vienna. The Great Hall measures 49 m x 22 m, while the Musikvereinsaal measures 49 m x 19 m, as long but slightly narrower. 

The narrow shoebox shape that Leeds shares with Vienna results in strong side wall reflections, which add clarity, intimacy and loudness to the sound impression.  (The seating capacity of the two halls is also similar: Leeds seats 1,563 people in its current concert configuration while Vienna seats 1,744.)

The second similarity is that the back and side balconies in the Great Hall are quite high above the floor of the stalls level, like in the Amsterdam Concertgebouw. At the Concertgebouw, the high balconies trap sound and send it back to the audience at a slight delay from the side wall reflections, and it was clear that the back balcony at Leeds Town Hall was doing the same. When I turned my head to the side, I could hear a lot of energy coming from the back of the room, far more than I would expect if there were a low balcony or no balcony at all. This early-arriving energy from the rear under-balcony corners, shown below, certainly contributed to the clarity and immediacy of the sound at my seat but also must have also contributed to the spatial envelopment I experienced, the feeling of being gripped by the music on all sides.

What accounts for the low level of reverberant energy I heard, the unusually soft, smooth and succinct finish to each phrase of music? The 28 m-tall vault at Leeds is 10 m taller than the flat ceiling of the Grosser Musikvereinsaal, which implies a longer reverberation time than Vienna's 2.0 seconds. But during a recent overhaul, heavy, sound-absorbing curtains were installed over the clerestory windows, which have brought the reverberation time down, and with it, the reverberant level. The curtains, located high up on the side and back walls, affect only late reverberation and do nothing to dampen the strong early reflections that give the sound its clarity and impact. (The curved panels above the stage platform, also added during the overhaul, surely contribute further early reflections to the acoustic signature. A pity they are so ugly.)

My anxiety about whether my listening position may have been uncharacteristically good relative to other seats at Leeds Town Hall stems from one critical difference between the geometry of the room and that of the Musikvereinsaal or the Concertgebouw. It is not the vaulted ceiling, which has a radius small enough to obviate the acoustical defects commonly associated with curved ceilings, but rather the side walls, from which giant column bases jut out. In the Musikvereinsaal and Concertgebouw, the side walls are relatively flat, ensuring strong, broadband reflections from the whole orchestra to most seats in the audience. In Leeds Town  Hall, the column bases may reflect sound from some but not all parts of the orchestra to some but not all parts of the audience. I might have just gotten lucky! I hold out hope, however, that I did not, and that the rest of the audience was able to experience the same immersive, gripping acoustical environment that I did. I suppose it will take a return visit to confirm.

Program Notes

Leeds Town  Hall Sunday, March 6, 2016

Leeds University Chamber Choir Milette Riis, conductor

Antonio Lotti (1647-1740) Crucifixus

David Wikander (1884-1955) Kung Liljekonvalje

Ola Gjeilo (1970 — ) Unicornis Captivator

Leeds University Symphonic Wind Orchestra Sam Watson, Conductor

Martin Ellerby (1957 — ) Dona Nobis Pacem

Leeds University Symphony Orchestra and Choir Tim Gillies, conductor

Gustav Mahler Symphony No. 2 "Resurrection"

[fromthesoundup]

The Sound of the Industrial Revolution

While in Manchester, I visited the Museum of Science and Industry to see—and hear—how cotton fabric was made in the mills of the 19th century. The museum maintains a working collection of mill equipment and three times a day museum staff demonstrate each step in the cloth manufacturing process to visitors.

The museum’s brochure advertises the demonstration as “thunderous” and indeed, the machines were loud—incredibly loud. Here is a typical power loom in action:

That high-pitched smacking sound is made when the metal-capped end of the flying shuttle, a piece of wood that carries the weft thread, strikes the end of the shed.

And here is a video of a thread-spinning machine:

The exhibition guide pointed out that what we were seeing and hearing was a cut-down section of a typical machine, which would stretch the length of the factory floor. And a typical factory would contain not just one but many of these machines. Listening to just this small section, it was not hard to imagine why mill workers suffered from hearing loss (among many other ailments).

According to the exhibition guide, noise in the mills made normal verbal communication impossible, and gave rise to ‘mee-mawing,’ a form of exaggerated speech and miming.  In his memoirs of working in the Bancroft Weaving Shed, a mill that survived into the 20th century, Stanley Challenger Graham recalls:

The workers ... used to ‘mee maw’ to each other. This was using exaggerated lip movements with no sound so they can lip-read each other. If a weaver wanted to say something privately to another weaver she would place her mouth very close to her friend’s ear so nobody could see her lip movements.

Born out of necessity, mee-mawing became part of Lancashire culture, and has been immortalized by comic actors such as Hylda Baker: 

Special thanks to my friend Mei-Lun Xue for pointing me towards the Museum of Science and Industry.

[fromthesoundup]

Pitch Perfect: The Snape Maltings Concert Hall

On a cold, rainy weekend I made a pilgrimage to Snape, a village on the Suffolk coast of England, to listen to Arup's first concert hall, Snape Maltings. The hall is notable for its steeply-pitched ceiling, unusual for a concert hall. What would this do to the sound?

Snape Maltings Concert Hall was commissioned in 1965 to serve as the principal venue for the Aldeburgh Festival. The summer festival, founded in 1948 by composer Benjamin Britten, his partner, singer Peter Pears, and writer and producer Eric Crozier, had outgrown a number of small venues in and around Aldeburgh, and when a maltings plant in the area shut down, Britten saw the potential to turn the largest building in the complex into a performance venue. Britten wrote a letter to engineer Ove Arup, who in turn called Derek Sugden, an architect and partner of Arup Associates. In an interview, Sugden recounts:

Ove rang me up and he said, 'You better go and see them!' I remember he just said that. So I went along. I went and met Britten and Pears and walked round it and thought, 'Gosh, it's in a terrible state.' All Britten said was, 'I would like it as full as possible for the volume' so I decided to go for 10 cubic meter per seat and that meant raising the walls another meter, which we did. And everybody liked it.

Two years later, the concert hall was destroyed in a fire. Again, Sugden:

The phone went about 7:00 - I think it was on a Sunday morning - and [Sugden's wife] Jean came rushing up and she said, 'Snape has burned down!' Jean and I got in the car and drove up and met Britten and Pears on the wet ashes. And I had a cry. He said, 'It's alright. I've got over it Derek now, we'll start building it straight away.' So I  I thought, 'Argh, getting all the drawings out.' And I said, 'Just as it was?' He said, 'Just as it was! Exactly as it was?' And it was back in 42 weeks.

Since opening and reopening, Snape Maltings gained a reputation for having stellar acoustics and paved the way for additional acoustic consulting projects at Arup, including Glyndebourne Opera House and the Bridgewater Hall. If it were not for Snape, I would probably not be working at Arup today (nor would I be writing this article).

The area around Snape is flat and marshy and when I visited at the beginning of March, the fields, trees and shrubs had yet to come back to life, adding further shades of grey to the overcast sky. Only the occasional daffodil punctuated the calm, expansive gloom.

Entering the concert hall, I felt as if I hadn't entirely left the surrounding landscape behind. The room, with its soaring timber ceiling, is awesome, yet a gloomy atmosphere pervades the room. The light in the room is quite dim and diffuse, turning the red brick of the walls and the blond wood of the ceiling grey. It is a quality that doesn't quite come across in photographs.

The low light contrasts with the dramatic structural form of the pitched ceiling. Why is the ceiling not more dramatically lit? Perhaps because the room is not meant to be experienced as an architectural space but as an environment, an extension of the outdoors. Other factors contribute to the feeling of being not-quite-inside: the unfinished timber, the rough brick...

... the wicker folding chairs...

... and the slightly chilly temperature. But it is the dim light more than anything else that defines the room's character.

While Snape's pitched ceiling does not draw the eye up as much as it might with more dramatic lighting, it does lift up the sound image, giving the acoustics a celestial quality that is more common in churches than concert halls. For the music on the program the day I attended—Haydn's sacred oratorio The Creation—the acoustics could not have been more appropriate. The sound was elevated, but also quite clear, warm and proximate. The sound was also large and full in shape. Too much sound energy coming from above can give the acoustics a  narrow, constricted quality (hence why adding an overhead reflector is not quite the panacea it is often made out to be), but in Snape, sound reflections from above are complemented by others from the sides as shown in the first and second-order raytracing diagrams below.

When I moved from my initial seat halfway back, just to the right of center, to a new seat four rows from the back, the sound image shifted further up. Here, near the top of the steep rake, with only about ten feet to the top of the brick walls, reflections from the pitched ceiling arrive earlier and relatively stronger than they do further down. The difference in sound impression caused by variations in the arrival time and strength of reflections does not make the acoustics at one seat at Snape better than another, but, I would argue, presents the repeat visitor with a subtly shifting acoustical landscape to explore. If I were listening to a more profane work, I would likely sit further down the rake, where the ceiling reflections will recede as the side wall reflections become relatively stronger.

It is surprising that in interviews and articles about Snape Maltings, Derek Sugden never brought up the concert hall's pitched ceiling. But in the 1960s, shape was not something acousticians really talked about. When Sugden began working on the commission, reverberation time was still seen as the sole measure of a concert hall's acoustical success or failure. Reverberation time dictates a relationship between sound-absorbing surface area and volume but does not put any limitations on the room's shape. Hence Sugden may not have thought the pitched ceiling particularly worthy of comment.

The still below, from a 1970 BBC news feature, shows Sugden with a chart of the room's unoccupied and occupied reverberation time curves...

...measured by firing a starting pistol, playing sine sweeps through a synthesizer and setting off a controlled explosion.

In the decades following World War II, reverberation time provided a scientific foil for architectural experimentation. The pitched ceiling at Snape, the vineyard terracing of the Berlin Philharmonie and the incredible width of Royal Festival Hall were all architectural concepts sanctioned by confidence in shape-agnostic reverberation time predictions.

It is less likely that the pitched-ceiling concept would have met with approval prior to the advent of scientific room acoustics at the turn of the twentieth century. Before W. C. Sabine published his landmark formula for predicting reverberation time, architects had no scientific metric for predicting acoustical quality and thus has to copy the shape of rooms known from experience and by reputation to have good acoustics. Hence the proliferation of shoebox-shaped halls in the 19th century, which derive from flat-ceilinged palace banquet rooms and ballrooms.

The pitched ceiling is also less likely to have been proposed in the 1970s or '80s, when new parameters for acoustical quality, such as the "initial time delay gap" and "lateral fraction" began to put increasing constraints on room shapes. Acoustician Leo Beranek, who proposed a whole raft of new parameters in his 1962 book Music, Acoustics and Architecture, can lay claim to being one of the only acousticians besides Sugden to oversee the design of a pitched ceiling in a concert hall—Tokyo Opera City Concert Hall, shown below (courtesy TOC). But the idea was the architect's, not his, and in his memoirs he writes that he was so uncomfortable with the shape that he insisted that the architect install sound-absorbing diffusers all over the ceiling and hang a massive rectangular reflector above the stage.

I loved the sound of the concert hall at Snape Maltings not because it was equivalent to a traditional, flat-roofed shoebox, but because it had a character all its own that would not be possible without the pitch. I hope to return again to continue exploring the various shapes of elevated sound it makes possible.

Program notes:

Snape Maltings Concert Hall Saturday, March 5, 2016 - 7:30 PM

J. Haydn (1732‒1809) The Creation (Die Schöpfung), sung in English

Aldeburgh Music Club Choir Prometheus Orchestra Conductor: Edmont Fivet

Gabriel, Eve: Jennifer France Uriel: Mark Wilde Raphael, Adam: Stephen Gadd

[fromthesoundup]

Domestic Acoustics at the Wigmore Hall

Stepping into The Wigmore Hall feels a little bit like entering someone's living room. The entire floor is covered in carpet—a thick, springy, tufted carpet that makes one feel inclined to take off one's shoes. The room glows with warm light from sconces along the side walls. Mahogany wainscoting runs along the stage wall. Two paneled doors with handsome moldings and brass doorknobs lead backstage but, one imagines, could just as well lead to the kitchen of a Victorian townhouse, from which the stage manager might emerge bearing a tray with tea and biscuits for the performing artist.

Listening to a podcast on the history of the Wigmore Hall a few days later, I found that intimacy came up again and again when artists, directors and critics spoke about the room. Take current director John Gilhooly, for example:

If you've been doing a lot of concerts elsewhere, even very famous halls, and you come here you suddenly find yourself capable of sounds, of colors, of responses on a small, intimate level without being too small, but I mean you find yourself capable of things you didn't think yourself capable of... The colors and the sonorities and the variations of touch—the hall is so unbelievably alive to these nuances.

Or former Times of England music critic Hilary Finch:

I always sit on the back row. They put critics on the back row and at first I thought this is was an awful affront when I started, and now I see why, because the sound's marvelous at the back.

At the Wigmore Hall intimacy seems to come at the expense of spaciousness. I didn't experience any claustrophobia during either performance but I did find myself craving a bit more sonic breathing room. According to Hilary Finch, some artists feel the same way:

[Dietrich] Fischer-Dieskau I think never sang here because the hall wasn't big enough for him. But he came to talk about his life and drew a huge audience.

The intimacy has, however, benefited singers who are at the end of their careers and whose voices lack the power they had in their prime. Elizabeth Schwarzkopf, for example, gave her final recital at the Wigmore Hall in 1971.

The Wigmore Hall's intimacy is largely due to its narrowness—strong reflections arrive at each listener from the smooth side walls, shown below, soon after the direct sound, enlarging and amplifying the sound image. But I don't think the room's sound would be quite as intimate or quite as grounded if it did not break two "rules" of acoustical design.

The first rule: avoid carpets. Acoustics textbooks advise against wall-to-wall carpeting because it is sound-absorbing and can deaden the room. (Carpets are also a paint to clean, but that's beside the acoustical point.) Acoustician Michael Barron cites carpet removal as a key factor in improving the acoustics of a number of less-than-successful concert halls, and I for one have never entertained the idea of specifying one in the performing arts projects I've worked on. But at the Wigmore Hall, the carpet serves an important acoustical function: it helps to keep the reverberation time relatively constant regardless of whether the room is empty or full, so an artist can enjoy the same cozy acoustics while rehearsing as while performing to a sellout audience. If the carpet were removed, the room would become more reverberant, more spacious-sounding and less intimate during rehearsal, encouraging the artist to "overplay" in concert. Likewise, a poorly-attended concert may look empty but will sound full with the carpet in place.  

The second rule: avoid concave curves, especially shallow ones. "In rational acoustic design terms," Barron Michael Barron writes in his assessment of the Wigmore Hall, "one would criticize the concave ceiling." Concave curves focus sound energy, which can result in echoes, dead spots, image shift and poor integration among other nasty acoustical phenomena. But as I wrote in my previous post about the barrel-vaulted ceiling of the Bachkirche in Arnstadt, concave surfaces are not all problematic. The Bachkirche ceiling reflects sound to the audience more evenly than a flat ceiling would because its focal point is so high off the ground.

I have to admit that one of the reasons I moved seats at each concert was with the perverse hope of encountering one of the abovementioned acoustical defects. But I did not. From each seat, the sound was well-integrated and centered on the stage. So I decided to draw the path of sound in a cross-section of the room to better understand what I didn't hear.

The drawings below show that sound energy reflecting off the smooth, elliptical ceiling converges practically on a single point. I must have simply missed the sweet spot.

While one person in a given row is likely to receive a lot of energy from the ceiling (over 10 dB of amplification, according to a study by acousticians Thomas Wulfrank and Raf Orlowski), no-one else will receive much at all, which may explain why I felt the sound image to be so grounded from each of my seats. If the Wigmore Hall were to have a flat ceiling, or a curved ceiling that more evenly distributed energy from above, the sound from most seats might appear to lift up, become more elevated, more elegant, a little less immediate, a little less domestic.

Program notes:          

The Wigmore Hall Sunday, Feb. 28 - 7:30 PM

Alexander Ullman, piano

Frederic Chopin (1810-1849) Polonaise-fantasy in A flat major Op. 61 Berceuse in D flat major Op. 57 Piano Sonata No. 2 in B flat minor Op. 35 'Funeral March' -Intermission- Waltz in F major Op. 34 No. 3 Scherzo No. 2 in B flat minor Op. 31 Nocturne in C sharp minor Op. 27 No. 1 Mazurkas Op. 24 Ballade No. 4 in F minor Op. 52

Monday, Feb. 29 - 7:30 PM

Ralph Kirshbaum, cello Shai Wosner, piano

L. van Beethoven (1770-1827) 7 Variations on 'Bei Männern, welche Liebe fühlen' from Mozart's Die Zauberflöte in E flat major WoO. 46 Cello Sonata in G minor Op. 5 No. 2 -Intermission- 12 Variations on 'Ein Mädchen oder Weibchen' from Mozart's Die Zauberflöte in F major Op. 66

Cello Sonata in A major Op. 69

[fromthesoundup]

I am going on a second listening tour during the first two weeks of March, 2016, beginning in London and ending in Utrecht. Please join me on tumblr as I listen to and write about the architecture, acoustics and cultural context of performance halls in the United Kingdom, Belgium and the Netherlands. On my "grand tour” in October 2015, most of the halls I visited were constructed prior to the advent of scientific acoustics. This time, I will be visiting a number of venues built or repurposed in the 20th and 21st centuries. As with the last tour, the question motivating my trip is simple: what is the relationship between architectural form and sound?

[fromthesoundup]

‘Moderate Modern’ acoustics at the Vienna Staatsoper

I did not find myself thinking much about acoustics at the Vienna Staatsoper. I attended a performance of Mozart's Don Giovanni and the singing was so good, the acting was so good, the orchestra was so good, the staging was so good, and the story itself is so gripping that I felt transported out of the physical space of the theater. The fact that I did not pay much attention to the acoustics is in itself an indication of good acoustics. If the reverberation had been too long, or if the orchestra had overpowered the singers, or if there had been an echo, I would have noticed right away. Acoustic faults such as these would have constantly reminded me that I was sitting in a big room with over a thousand strangers surrounding me watching a staged production. In other words, bad acoustics make disbelief harder to suspend.

That said, when the lights came back up at intermission, I collected the few thoughts I did have in the fleeting moments when I felt removed enough from the performance to "hear the room." The Staatsoper is certainly not acoustically neutral, if such a character could be said to exist. From my seat, and I would imagine from most seats in the stalls, the sound was particularly strong at high frequencies. If I were to describe the room's effect on soprano Marina Rebeka's voice, I would call the acoustics "bright," as her voice came through loud, clear, brilliant and glimmering. If I were to do the same for the altos, tenors and basses in the production, however, I would call the acoustics a little "trebly," as they seemed to lack some support from below.

The Staatsoper's bright, or trebly, acoustics, are a product of the room's spartan reconstruction after the end of the Second World War by architect Erich Boltenstern,  shown below in a photo from the Vienna city archives. 

The Staatsoper's bright, or trebly, acoustics, are a product of the room's spartan reconstruction after the end of the Second World War by architect Erich Boltenstern. Boltenstern, shown below in a photo from the Vienna city archives, earned his architecture degree in 1923 and interned with both Antoni Gaudí in Barcelona and Hans Poelzig, designer of the expressionist Grosses Schauspielhaus, in Berlin. He also taught a masterclass under modernist architect and industrial designer Peter Behrens, whose influence is clear in Boltenstern's 1928 competition entry for a German theater in Brno shown below.

The first project Boltenstern realized was a crematorium in Graz, and he would go on to build numerous other crematoria and funerary buildings over the course of his career. In fact the only English language critique of his work I have found is in the Encyclopedia of Cremation, in which architecture historian Bruno Maldoner writes:

His buildings are distinguished by their great stillness and calm but complete lack of pathos. Their style is marked by a reduction to geometric simplicity, uniform measuredness with clear lines, and quiet elegance. The building shapes and interiors exhibit impressive proportions with forms devoid of any decoration.

Maldoner's description applies as well to the Staatsoper as it does to his crematoria. Compared to the Hofoper it replaced, shown below courtesy Austria-Forum, the Staatsoper is austere.  The muted color palette, the lack of ornament, the blankness and flatness of the ceiling are especially striking seen against the auditorium's non-modern shape. Boltenstern retained the original form of the Hofoper in his design but essentially stripped it bare. The end result could be seen as an architectural compromise, but I like to think that it was a more complex expression of Boltenstern's multiple identities as a modernist architect, a born-and-bred citizen of Vienna and a victim of Nazi repression (during the war he was labeled a "jüdisch versippten" for having a Jewish spouse, which made it nearly impossible to find work).

The smooth, unadorned surfaces of Boltenstern's Staatsoper reflect high-frequency sound like a mirror, preserving the high partials of the singers' voices. Ornament in the richly-decorated Hofoper, by contrast, would have scattered sound at high frequencies, resulting in a warmer and more covered sound with less brilliance. The trebly quality of the new Staatsoper is also a consequence of Boltenstern's decision to clad much of the room in wood (possibly because he believed the age-old myth that acoustics are the product of rooms resonating like a wooden string instrument). On the balcony fronts, the wood is glued directly to concrete, so the two materials act as one solid mass and reflect a broad range of frequencies. The wall surrounding the stalls, on the other hand, consists of thin plywood panels with a ventilation airspace separating them from the concrete. This assembly reflects higher frequencies off the wood and absorbs lower frequencies in its resonant cavity, emphasizing brightness at the expense of depth.

Curators at the Vienna Museum gave an exhibition of Boltenstern's work the title "Moderate Modern," and perhaps the same appellation could be applied to the acoustics of the Staatsoper: bright, dry and clear as in many of the so-called "hi-fi" halls of the post-Second World War period, but with the intimacy and intensity of a traditional opera house.

Program Notes

Wiener Staatsoper Monday, October 26 - 4:00 PM

W. A. Mozart (1756-1791) Don Giovanni

Direction: Adam Fischer Production: Jean-Louis Martinoty Scenery: Hans Schavernoch Costumes: Yan Tax

Don Giovanni: Mariusz Kwiecien Il Commendatore: Sorin Coliban Donna Anna: Marina Rebeka Don Ottavio: Benjamin Bruns Donna Elvira: Juliane Banse Leporello: Erwin Schrott Masetto: Jongmin Park Zerlina: Andrea Carroll

Orchestra of the Wiener Staatsoper Choir of the Wiener Staatsoper Stage Orchestra of the Wiener Staatsoper

[fromthesoundup]

Why I can’t review the Philharmonie de Paris but why it’s worth trying anyway: a meditation on variability.

Every time a new concert hall opens, critics rush to say something about the acoustics but usually add a disclaimer along the lines of, "It's really too soon to say because the orchestra needs time to adjust," or, "The Ode to Joy with live acrobatics was not really a representative program." There's another reason why it's hard to judge the acoustics on opening night, however, which is that it's impossible to assess the acoustics of the hall from a single seat. Variation in the sound field is not only a problem in assessing new halls but a more general problem in room acoustic design and analysis. The problem is a can of worms that I will open but will not attempt to close by the end of this post. 

 Variation in the sound field is the topic of this post because it is all I could think about after my experience in the brand-new (or, more accurately, yet-to-be-finished) Philharmonie de Paris. During a single concert, I experienced what might have been the worst concert hall acoustics of the tour, followed by what might have been the best. I have to thank the conference organizers, who waited until last minute to buy tickets and ended up with the seats no-one else wanted, otherwise I would neither have sat where I was seated nor would I have been as motivated to seek out the best seat in the hall after the intermission.

My assigned seat was to the stage-right side of the orchestra in what is known as the "1st balcony." (It is not really a balcony, because it doesn't cantilever over anything and it isn't that high above the orchestra, but my ticket called it a balcony, so fine, I'll call it a balcony). As soon as the orchestra began, I cringed and wrote down, "It sounds terrible." Not a good start. The balance was way off, with the 1st violins barely audible and the woodwinds super-strong, and there was very poor integration between direct sound and reverberation, making the hall sound cavernous. These issues weren't helped by the fact that the Orchestre de Paris is, well, not quite in the same league as, say, the Wiener Philharmoniker or the Berliner Philharmoniker or the Concertgebouworkest. Many of the players looked and sounded bored, which may not have been so apparent sitting some distance in front of the stage, but I was sitting right next to them, so when one of the horn players started nodding off in the middle of the concerto, all I could do was stare and feel sad. My only consolation was that I was seated next to Jürgen Meyer, an acoustician whose work on the relationship between acoustics and musical performance I deeply admire (and whom I have quoted a few times in this blog), and his wife, and I was able to commiserate with both of them.

As the final movement of the cello concerto came to a close, I scanned the room for empty seats and decided the most promising one would be directly opposite but on the "2nd balcony," a true balcony much higher up than the so-called balcony where I was sitting. 

My instinct was right. From my new perch high above the orchestra, the sound was very present, well-blended, spatially enlarged, and clear but lush, this last contrast a rare sonic quality that I only experienced once before on the tour, in the Speyer Cathedral crypt. I heard a light, blurred echo from the far left side of the room, but it was not distracting and instead gave a sense of sonic depth to the room. 

Overall, the sound was great, but I thought it could get even better. So during a break between the two movements of the symphony, I left my seat and crouched down at the bottom of the stairs so that I could see and hear almost the entire orchestra unobstructed. 

The sound became even more powerful, even clearer, and I realized that I was hearing the exact sound that I longed for in Berlin, a sound in which I could pick out every individual part but in which all those parts blended together perfectly. And no wonder, really—I was at such a steep angle above the orchestra that I could see and hear each instrument clearly (I could even see the front faces of the second violins right below me), but far enough away that the direct sound did not dominate the sound of the room. The sound gave me goosebumps and made me sweat. I gripped the bars of the balcony railing the whole time. It was exhilarating.

So, when people ask me how the Philharmonie sounded, I don't know what to say. From the two sections I sat in, it sounded terrible and it sounded amazing, and it is hard for me to reconcile these two experiences to sum up the overall sound of the room. If someone were to ask me how the Philharmonie looked, it would be much easier, even though the visual experience was also very different on the second balcony compared to the side of the stage. We lack language, let alone the cognitive capacity for reconciling differences of auditory experience within one space, whereas we are quite good at abstracting localized visual experiences and reassembling them into a coherent, meaningful whole. Regardless of where I was sitting, it would only take a quick glace to determine that the room has a stage at the center, a low and black-colored ring of seating surrounding it, a number of discontinuous and different-colored balconies higher up, a number of white-painted and wood-veneered reflectors above them, and a white wall and ceiling surrounding the upper level, with all of the forms sinuous in form. I could not make the same summary after a sonic glance or even a series of sonic glances. The discreet objects that stand out in one's eyes—the stage, balconies, reflectors, and so on—all blend together in one's ears because of the way the brain integrates the room's sound response (unless there is a distinct echo). So when I moved from the side of the stage to the second balcony, I could reorient myself to the individual components of the room, which remained identifiable and coherent despite the radical change in perspective, but I could hear only the sum of the changes to the room response, and because those changes really added up, my new acoustical environment sounded completely foreign from the last.

I was not surprised to hear such extreme differences in a hall like the Philharmonie de Paris. It is well-known that the acoustics in a surround-type hall will vary much more than in a shoebox or a fan-shaped room (more on this shortly). I was surprised, however, that neither the acoustical brief for the concert hall, written by Eckhardt Kahle of Kahle Acoustics, nor the papers delivered at the conference by the hall's acoustical designers, Howard Marshall, Christopher Day and Thomas Scélo of Marshall Day Acoustics, explicitly addressed the issue of variability. Acoustical success was predicated on (and more or less achieved by) meeting acoustical targets averaged across a number of different seats in the completed hall, as shown in the chart below, reproduced from one of the papers Marshall Day presented at the conference.

Why did the acousticians involved in the design of the Philharmonie de Paris pay so little attention to the hall's inevitable acoustical variability? History provides some clues as to why variability has long been and remains sidelined in room acoustics analysis and design. 

Wallace Clement Sabine, the so-called father of architectural acoustics, was an avid mapper of acoustical variability. Inspired by Geodetic Survey maps, he created some beautiful contour drawings of loudness levels in rooms, such as the one below, by playing a tone on a portable organ and meticulously noting the level at different locations.

Despite how attractive his drawings look, Sabine saw acoustical variation as a phenomenon to be avoided because he considered it to cause "deaf regions" in a room's sound field. In his collected papers on room acoustics, Sabine discusses variation along with echoes and excessive reverberation in a chapter called 'Correction of Acoustical Difficulties.' Even though Sabine writes about variability primarily in relation to rooms for speech, his negative attitude towards the phenomenon extends by implication to rooms for music and surely influenced following generations of acousticians designing rooms for music.

Along with Sabine's admonitions against variability, a number of other forces in the early-to-mid-20th century conspired to create hundreds of auditoriums with highly diffuse sound fields in which the only real variation was loudness, a function of distance from the stage. These forces included the influence of recorded music on listeners' expectations; the influence of acoustically dry recording studios and movie theaters on design models; the commercialization and marketing of acoustic panels and other sound-absorbing products; and growth in audience sizes, requiring fan-shaped forms with weak early reflections. (For in-depth analyses of these and other forces, see Emily Thompson's book The Soundscape of Modernity or chapter 8 of Michael Forsyth's book Buildings for Music.) The Beethovenhalle in Bonn, completed in 1959, is a good example of one of these halls. Shown below in images reproduced from the first edition of Leo Beranek's Music, Acoustics and Architecture, the Beethovenhalle is fan-shaped in plan and has a distinctive sound-diffusing ceiling, meant to prevent focusing from the domed ceiling and thus promote an even sound field.

The problem with highly diffusing halls is that although they sound similar everywhere, they do not sound very good anywhere. Without strong early reflections, the sound image tends to be very frontal and distant unless you are sitting right at the front.

The era of highly diffuse, fan-shaped auditoriums is now over but our understanding of variation in the sound field (and our recognition of its value to design) is still lacking, hampered by another legacy of Sabine's work.

Sabine's most enduring legacy is a formula bridging the physics and the psychoacoustics of sound in a room. His formula for reverberation time allows one to predict the amount of time it will take for a sound to die away in a room given the room's volume, surface area and absorptivity. Sabine used the formula to design Boston's Symphony Hall, today regarded as one of the best-sounding concert halls in the world, and over a hundred years later, acousticians still use it, unchanged, to do basic predictions. The most interesting thing about reverberation time, in the context of this post at least, is that it doesn't change much from seat to seat in most concert halls. It only changes significantly in seats far removed from the main volume, such as deep under a balcony. This means that it's possible to get the reverberation time "of the room" by averaging the reverberation times measured at a number of different seats in the hall.

For many years, reverberation time was taken to be the sole measure of acoustical quality in rooms for music. When acousticians discovered (or more accurately, redisdovered) the importance of early sound to the listening experience, they introduced new measures, such as "Definition" (D-50) and "Lateral Fraction" (LF), to be used alongside reverberation time in the analysis and design of concert halls. (See this paper for a glossary of room acoustics parameters as of 2008—the number of parameters continues to grow and grow). Unlike reverberation time, many of these new measures do not remain steady across the audience area. Even in a highly diffuse hall, LF, which measures the ratio of sound arriving from the sides compared to the front and back, will vary a lot, with listeners at the very front getting much more lateral energy than listeners further back. Still, LF and other measures are very often averaged following the analysis model established for reverberation time.

Why not analyze LF and other measures in a more spatially distributed way to acknowledge their variance across the audience area? Besides habit from the study of reverberation time, I can think of a few other reasons. One is that it is hard to know how many positions to study. ISO-3382—Acoustics—Measurement of Room Acoustics Parameters section A.5 provides some guidance on how many measurements to take, as shown below, and suggests that the microphones be "evenly distributed over all audience seating areas." 

But the acoustics can change quite a lot even from row to row, a phenomenon I experienced sitting in the front row of the top tier of the Garnier Opera in Paris. When I leaned my head back so that it almost touched the knees of the man sitting behind me, the sound was muffled and remote. When I leaned my head forward so that my ears were more exposed to the main volume of the room, the sound became louder and brightened considerably.

How many measurements must be taken to get a full picture of acoustical variability in a concert hall? In his pioneering survey of concert halls, Leo Beranek did only two measurements per hall, one halfway back at orchestra level and one halfway back on the first balcony. He picked these two positions because, he wrote, "Music critics normally occupy [these] seats." (See my previous article for more on the survey and on the circular logic for this choice). ISO-3382 suggests 10 positions for a hall upwards of 2000 seats.

Some recent studies have attempted to more accurately quantify the number of recording positions required. A 2010 paper by researchers at the Institute for Technical Acoustics at RWTH Aachen studied differences in LF across the audience areas of four halls in Germany and concluded that for a resolution of one degree of "just-noticeable-difference," measurements should be taken 0.3 m apart, a distance of less than a chair's width! A map of their measurement results in the Leipzig Neues Gewandhaus and a chart showing variance in all four halls are shown below.

Another 2010 paper, this one by researchers at Kyushu University, mapped parameters taken from a staggering 1427 measurement positions in one hall. Their conclusion was similar to that made by the Aachen researchers—ie. that many positions are in fact needed to accurately capture variance in the sound field. They also concluded that contour maps are a better way of communicating measures than tables of data or single values.

What would a measures map look like for the Philharmonie de Paris? We may never know unless a meticulous study is carried out like the ones mentioned above. Nevertheless, I have attempted to make a very crude, unscientific map of the Philharmonie based on my own experience along with reviews from other acousticians at the same concert and newspaper reviews from France, the United Kingdom, the US and Germany. I have reduced each review to "good," "so-so" or "bad," and mapped it to the seat or, lacking an exact seat number, the approximate location that review was made from. This is what the map looks like as of November 14, 2015 (I am still waiting to hear back from Tom Service at the Guardian, who did not provide any information about where he was sitting in his gushing review of the hall).

The reviews from the rear and sides of the stage are all from acousticians and are all negative with one exception, a positive review from the a side seat near the back of the "1st balcony." My positive reviews are from the 2nd balcony, stage left. (The happy face on the edge of the balcony should actually be especially happy-looking). The reviews from orchestra level facing the stage are almost all from newspaper reviews, and show a mixed reaction. The happy face at the edge of the balcony facing the stage is from David Griesinger, an acoustician and sound engineer who is a big fan of clarity. I have listed the newspaper reviews cited at the end of this post.

Beyond good, bad and ok, I would like to briefly speculate on what the different acoustical characters of the Philharmonie de Paris might be, or might have been had the acoustical designers recognized the value of difference in the sound field. High above the orchestra, the sound can be a landscape with a mix of localizability and blend, and with envelopment created by reflections from the ceiling corners. The acousticians largely achieved this, whether intentionally or not. At the front of the orchestra level, facing the stage, the sound has the potential to be spacious and strongly enveloping, as I experienced sitting at the front of the Haydnsaal. In the middle of the orchestra level, facing the stage, the sound can be broad and tall and balanced. At the back of the orchestra level, the sound can be intimate, with a sensation of being closer to the orchestra sonically than visually, as I experienced in the Schwetzingen Rokokotheater. Beside and behind the stage are more challenging zones acoustically, but perhaps there are ways to make the inevitable imbalances more engaging and less distracting.   

These are just some initial speculations. I hope in my own work as an acoustical-architectural designer to be able to more deeply investigate the potential of acoustical variability, which has for so long been either seen as a negative quality or as something to be ignored, to positively contribute to the character of rooms for music.  

Program notes

Philharmonie de Paris Thursday, Oct. 29, 2015

Orchestre de Paris Director: Paavo Järvi Organ soloist: Thierry Escaich Cello soloist: Sol Gabetta

Thierry Escaich (1965—) Improvisations

Camille Saint-Saëns (1835-1921) Concerto for Cello, op. 33

Intermission

Camille Saint-Saëns Symphony no. 3 "with organ," op. 78

A selection of newspaper review of the Philharmonie de Paris

Francis Carlin for FT

Alex Ross for the New Yorker

Anthony Tommasini for the New York Times (I)

Anthony Tommasini for the New York Times (II)

Marshall Marcus for his own blog

Tom Service for the Guardian (no seat location)

Olly Wainwright for the Guardian (architecure review, no seat location)

Marie-Aude Roux for Le Monde

Eric Loret, Clément Ghys and Guillaume Tion for Libération (no seat location)

Rémy Louis for Diapason (no seating location)

Manuel Brug for Die Welt (no seat location)

Frederik Hannsen for Der Tagesspiegel (no seat location)

Christine Lemke-Matwey for Die Zeit (no seat location)

Götz Thieme for the Stuttgarter Zeitung

Robert Braunmüller for the Munich Abendzeitung (no seat location)

Marc Zitzmann for the Neue Zurcher Zeitung (no seat location)

[fromthesoundup]

Why does the Musikverein have “the best” acoustics in the world?

“The Mecca of the old halls of Europe.” “The holy grail.” “Certainly the finest hall in the world.” “The most venerable of all the old halls of Europe.” “The most famous of the shoe-box shaped halls.”  “Indisputably one of the most admired concert halls in the world.” “The best concert hall in the world.”

While a small number of other concert halls vie for the title of “best acoustics in the world,” the Grosser Musikvereinsaal always seems to come out on top. The comments above are just a small sampling of the superlatives it has garnered from acousticians, conductors and music critics.

Rather than weigh in on whether the Musikverein’s acoustics are in fact the best, I would like to investigate how its acoustics became the gold standard and what it means for concert hall design.

My review. But first, ok, I will weigh in on the Musikverein’s acoustics—but I’ll make it brief. I attended two concerts in the Grosser Musikvereinsaal, one a special Austrian National Holiday concert of Strauss waltzes performed by the Wiener Johann Strauss Orchester and the second a subscription concert performed by the Cleveland Orchestra. I regret that I was not able to secure a ticket to hear the Wiener Philharmoniker perform, especially because the orchestra knows how to play in its own hall better than any other orchestra.  The Wiener Philharmoniker performs in a unique layout with double basses at the back of the stage and plays on instruments that differ from those used by other orchestras, further differentiating its sound in the hall. Despite listening to orchestras that do not fit the Musikverein like a glove, the acoustics of the hall are, physically speaking, linear, and thus respond the same way to any sound impulse, so I feel that I heard enough to pass preliminary judgment. (Acoustician Tapio Lokki might dispute this claim—see his discussion on the relationship between linear physical acoustics and the nonlinearities of performance and human hearinghere).

During the first concert, I sat on the centerline almost exactly halfway back. During the second concert, I sat a little off center about two-thirds of the way back. The acoustics from both positions were good, ticking the boxes of appropriate reverberation time, high sound strength, high clarity and even blend. The tonal balance was excellent, both bright and strong in bass. This combination made Messaien’s Couleurs de la Cité Céleste, a piece for piano, winds and percussion, particularly impactful. The clarinets and brass were piercing and the percussion instruments really boomed in the space. The 2.0 second mid-frequency reverberation time, considered ideal for Classical and Romantic orchestral music but too long for most 20th-century art music, added a kind of ironic luxuriance to the sound. The combination of long, smooth reverberation with tonal brightness gave the music a cold splendor. In my notebook, I wrote, “The sound during one long blast from the brass is unique so far—cutting, searing, like a knife. Not a jagged sound, because so clear, so smooth. If I ever get knifed, I imagine this is what it will feel like.” The Messaien piece was the highlight of both programs for me, but I don’t think most of the (rather elderly) audience agreed, as shown in the photo below, which I took right when the tepid applause began.

The spatial quality of the sound was a little disappointing. I did not experience the hall’s reputedly strong envelopment. Instead, I heard a horizontally broadened but vertically compressed source with little energy coming from behind. The focused, frontal sound was not nearly as involving as in the Haydnsaal, the slightly smaller shoebox hall I had just visited. Despite the responsiveness of the hall to dynamic changes, the vertically-compressed source image grounded the sound so that even during the most dramatic crescendos, the music never seemed to “lift off.” I suspect the Grosser Musikvereinsaal’s frontal, broad and compressed acoustics are largely due to strong second-order reflections off the balcony undersides, which reinforce first-order reflections off the side walls to create a low and wide directionality. In the Haydnsaal, the lack of side balconies meant that the side reflections were weaker and thus did not mask reflections coming from above as much, allowing the source to grow vertically as well as horizontally.

The invention of excellence. Interestingly, the Musikverein’s acoustics have not always been the ultimate acoustical benchmark. According to acoustician Michael Barron:

A curious aspect in the history of concert halls is that the Vienna Musikvereinsaal, which has such a reputation today, was little mentioned [in the first half of the 20th century]. Neither Sabine (1922) nor Bagenal and Wood (1931) refer to it. Nor did the architects, Gropius and Schmieden, of the Neues Gewandhaus in Leipzig. This new Leipzig hall served as the worldwide model of excellence before the Second World War. From the point of view of reverberation time, this reputation proves to be somewhat surprising… While [its] reverberation time of 1.55 seconds would be suitable for late Classical or early Romantic music, it would certainly today be judged as too short for the main Romantic symphony repertoire.

How then did the Grosser Musikvereinsaal take the place of the Neues Gewandhaus (shown below in a colored woodcut reproduced in Michael Forsyth’s book Buildings for Music) at the pinnacle of acoustical excellence?

The Musikverein’s acoustical preeminence owes a lot to acoustician Leo Beranek’s pioneering survey of concert halls that began in 1955 and has continued to the present day. Beranek carried out the survey as research for the design of New York’s Philharmonic Hall, part of the Lincoln Center performing arts campus. The initial survey consisted of interviews and questionnaires of conductors, music critics and a few connoisseurs. The table below, reproduced from the most recent survey publication, shows the respondents along the x axis, the ranked halls represented by numbers along the y axis, and the respondents' rankings in the cells.

The next table in the same article reveals the hall ranking with the Grosser Musikvereinsaal at the very top.

Even though the first edition of Beranek's survey book, published in 1962, hid the names of the halls in the ranking (perhaps for political reasons) and the second major edition did not explicitly rank halls within their letter-grade categories, it is not hard to read between the lines.While some of the other halls have moved up and down since the initial survey, the Grosser Musikvereinsaal has remained at the top.

To achieve a more scientifically rigorous rank ordering, Beranek developed objective psychoacoustical parameters such as brilliance, texture, and initial time-delay gap. Beranek created these objective parameters based on the outcome of his subjective studies, so it should not be surprising that the Musikverein came out on top again. Recently, acoustician Magne Skålevik used new survey data to contest some of Beranek’s rank ordering methods but found that the Musikverein came out on top yet again, as shown in the table below.

In a paper on the Musikverein presented at last week’s Auditorium Acoustics conference, acoustician Tapio Lokki presented the results of a new listening study in which he and his colleagues at Aalto University found that the Musikverein did not “stand out in the indicated preferences.” Despite this finding, I think it’s highly unlikely that any other hall will knock the Grosser Musikvereinsaal off its pedestal in the foreseeable future. The following are some reasons why the Musikverein will remain known as the best even if it is not the best or there is no best: 

1. Accessibility. In his rank ordering paper, Beranek writes:

One problem is that no person interviewed is well acquainted with more than one-third of the 65 or so concert halls that I have recently asked about… The process was easier when there were fewer halls, because most halls were well known by many of the persons contacted. A plethora of halls has been built since 1980, and the subjective assessment of their relative acoustical quality has become ever more difficult.

One of the most basic reasons the Grosser Musikvereinsaal will continue to be known for having the best acoustics is that it is relatively accessible to listeners compared to many other halls. Beranek’s table above shows that considerably more interviewees had been to the Musikverein (#1) than to the Concertgebouw (#5), or to Beranek’s own Tokyo Opera City Concert Hall (#6), or to a number of other halls.  

The Musikverein is accessible for a number of reasons. First, it is geographically located in Vienna, a major city in central Europe. Second, music is played in the Grosser Musikvereinsaal all the time, if not always by ensembles as renownedas the Wiener Philharmoniker. One of the reasons I skipped the above-mentioned KKL on this tour is that it does not host many orchestral music performances outside the summer Lucerne Festival. Third, the hall’s reputation (which I will talk about next) makes it more accessible psychologically. When I planned the tour, the Musikverein’s program was the first I checked simply because it came to mind before any other European hall.  

Could an abandoned warehouse in Siberia such as the one shown below,courtesy English Russia, have acoustics that outshine those of the Grosser Musikvereinsaal?

Possibly. But consider the age-old question, “If a tree falls in a forest and no one is around to hear it, does it make a sound?” Can we speak of acoustics if music is never played into a room and an audience never assembles to listen? From an analytical standpoint, I’m not sure. It might not be appropriate to include a space such as the hypothetical one above in a list of the best-sounding rooms in the world. But from an instrumental, design-oriented standpoint, of course we should value “found” acoustics and “lost” acoustics as much as rooms that are highly accessible. I adopt this view from my colleague Alban Bassuet, whose survey of historical rooms for music as part of the Constellation project revealed amazing acoustical phenomena in spaces where music is no longer or rarely played. The results of the survey have strongly influenced design work at Arup on rooms for music. 

2. The weight of reputation. Reputation is the basis of Beranek's ranking system. It also grounds the objective parameters he developed to more scientifically compare concert halls. Reputation depends a great deal on accessibility and on time, two factors that help the Grosser Musikvereinsaal retain its top spot and prevent halls that are more remote or newer from challenging it. Unlike people, whose longstanding reputations can be tarnished or destroyed overnight, concert halls are impassive, unchanging vessels for music (unless they are renovated) and are thus more impervious to changes in reputation. 

Why does reputation matter so much in the assessment of concert hall acoustics? If acoustics is a science, shouldn't hard facts matter more? 

Hard, physical facts cannot serve as the basis of comparing concert halls because the ultimate object of room acoustics science is us, people, and we listen to music because of its emotional power and its cultural resonance. Physics can explain how sound propagates in a room but it is far less useful for explaining what sound means to us when it arrives at our brains. This explains why reputation, a cultural-psychological construct, makes more sense as an arbiter of acoustical quality than, say, a single physical measure, like the amount of energy arriving at one's ears over a period of time.

Sound reproduction technologies would appear to give us more accurate means of comparing acoustical environments than reputation. In Arup's SoundLab, for example, we are able to reproduce any sound environment over a loudspeaker array using Ambisonics surround sound technology. And by convolving the same anechoic sound sample with different room impulse responses, we can directly compare the acoustics of those rooms. Our controlled listening studies have not yielded a clear ranking of concert halls, however, and have instead exposed the plurality of preference and taste for different acoustical environments. Our findings are often harder to communicate than a ranking, however, because we often lack appropriate objective parameters or technical language to describe what we hear. Getting more people to simply listen is also a challenge. It is easier for most would-be-critics of concert hall quality to get a ticket to the Musikverein than to get access to a dry, noise-isolated room with an Ambisonics speaker rig like ours. It is easier to make the sounds of different concert halls available by a technique known as binaural playback, which allows the listener to hear the 3D sound environment over headphones. But the technique requires a filter based on the listener's head shape, and everyone has a different head shape, so barring every listener getting his or her head scanned, the playback will not be consistent from listener to listener.

Even Tapio Lokki, who has dedicated a great deal of research energy to demonstrating and clearly communicating how people have different acoustical preferences, cannot escape the specter of reputation, and more specifically, the Musikverein's reputation. In the introduction to a recently-presented paper entitled, "The Secret of the Musikverein and Other Shoebox Concert Halls" (the first page of which I have reproduced above)  writes,"Considering the reputation of the golden hall, the listening test results are surprising, as the Musikverein does not stand out in the indicated preferences." Rather than investigating why the Musikverein did not stand out, he then goes on to find new reasons for why the Musikverein should still be number 1!  

3. Influence, real and exaggerated. The Musikverein’s shape has inspired the design of numerous halls starting from the mid-20th century. In my post on the Amsterdam Concertgebouw, I commented that despite the hall’s excellent reputation, very few modern halls (none to my knowledge, in fact) have been modeled after its proportions. There are plenty of examples of halls modeled after the Grosser Musikvereinsaal’s proportions. Beranek’s firm BBN consulted on a number of narrow, shoebox-shaped rooms, including the original design of Philharmonic Hall and Tokyo’s Opera City Concert Hall. Russ Johnson, an architect who worked with Beranek at BBN and went on to found Artec, was perhaps the strongest advocate of Musikverein-style shoebox halls. Halls shaped by Artec include the Maison Symphonique de Montreal, Meyerson Hall in Dallas and KKL in Lucerne, shown below (courtesy of the Lucerne festival).

Arup, the firm where I work (and the firm into which Artec has been integrated) has also designed a number of halls modeled after the Musikverein, including UK venues Milton Court and King’s Place, shown below (courtesy Robert McAlpine).

The sheer number of halls that more or less follow the Musikverein’s proportions burnishes its reputation for acoustical greatness to the extent that it is easy to mistakenly assume that it served as the inspiration for all subsequent shoebox-shaped rooms. The Grosser Musikvereinsaal is sometimes misattributed as the inspiration for Boston’s Symphony Hall (see Forsyth’s Buildings for Music for one example), whereas it was in fact the Neues Gewandhaus that served as the model for Sabine’s collaboration with McKim, Mead and White, as documented by historian Emily Thompson in her book The Soundscape of Modernity. The Musikverein’s influence is also sometimes over-exaggerated. New York Times architecture critic Nicolai Ouroussoff, for example, writes:

For more than a century the conventional wisdom for creating a great acoustical hall was a narrow, high, rectangular “shoe box” model with a maximum of 2,500 or so seats. The holy grail was Vienna’s 1870 Musikverein, a Greek Revival invention of the Danish-born architect Theophil von Hansen.

It is possible that Ourossoff simply paraphrased acoustician Chris Jaffe, who writes in his book The Acoustics of Performance Halls:

For over a century, the Grosser Musikvereinsaal in Vienna has been considered the keeper of the keys, the one hall against which all others must be measured if one is to achieve the “traditional” nineteent-century orchestral sonic experience.

Jaffe's claim both extends the influence of the Musikverein further back in time than evidence supports and also neglects other concert hall archetypes that were influential in the twentieth century. The Greek Amphitheatre was in fact more influential as a model for concert hall design in early to mid-twentieth century than the shoebox, inspiring architects from Hans Poelzig to Alvar Aalto to Carlos Raúl Villanueva. In fact, the majority of halls shown in the first edition of Beranek's book are either amphitheater- or fan-shaped.

4. Excellent stage acoustics. Many of Beranek’s interviewees were conductors, which skews the results of his ranking towards halls that have good stage acoustics as opposed to good audience-area acoustics, the primary focus of the book. The Grosser Musikvereinsaal has an excellent reputation among conductors.  One of the quotations in the opening paragraph of this post is from Bruno Walter. In full it reads:

This is certainly the finest hall in the world. It has beauty of sound and power. The first time I conducted here was an unforgettable experience. I had not realized that sound could be so beautiful.

Compare this encomium to Yannick Nézet-Séguin’s characterization of the Concertgebouw’s stage acoustics as “dangerous.”  (See my earlier post on the Concertgebouw for more reviews of its poor stage acoustics.) The Concertgebouw is, of course, a challenger to the Musikverein’s number one rank. Its stage acoustics are surely one reason it is considered slightly inferior, even if they do not reflect the acoustics from the best audience seats at all!

There are a number of reasons for the Musikverein’s good stage acoustics. One is that the orchestra gets a lot of support from early reflections. The “cueball” reflections off the balcony undersides are particularly critical, because they allow different sections of the orchestra to hear each other clearly. Another reason is that the small stage size forces musicians to sit close together so that they play as a more compact unit. This might not make visiting musicians particularly happy, especially when they find their backs against a wall or their elbows knocking into each other as can be seen in the photo of the Cleveland Orchestra below, but from the conductor’s podium, the orchestra sounds tighter.

Still another reason is that the hall’s geometry is continuous between stage and audience areas, as shown below, creating a more unified acoustical environment than in most halls, especially those with orchestra enclosures like Boston’s Symphony Hall.

5. Other experiential factors. Listening to music in a concert hall, it is nearly impossible to psychologically extricate the acoustics from other aspects of the experience, including the music played into the room, the view of the performers on stage, the light level, the comfort of the seats, and the social context of the event. These aspects don't need to be completely sorted out when reviewing the overall experience of a hall, but for the purpose of scientific comparison or for design, they can create a bias.

While there are many experiential factors that make the Grosser Musikvereinsaal unique, two stand out that have a strong bearing on the appreciation of its acoustics. The first is the Wiener Philharmoniker. The orchestra is one of the world's best, and, as I mentioned above, it plays in a special layout with special instruments that suit the acoustics of the hall. A bad orchestra can make good acoustics sound worse than they are. Conversely, a good orchestra can make bad acoustics sound better than they are.

A second factor is the visual quality of the hall. The Grosser Musikvereinsaal is known as the "Goldener Saal" because much of the interior is covered in gold-colored paint, as shown below in pictures from a 1987 pictorial souvenir book. A number of lab studies have shown that people's perceptions of sound change depending on the color they're shown. So it is certainly possible that if the Musikverein were painted black it would "sound different" and would have a very different reputation.

In addition to vision directly influencing hearing during a concert, the gold-ness of the Musikverein also affects expectations of what the room will sound like. My colleague Alban Bassuet and I once began a lecture at Rice University asking music students what they thought various rooms would sound like just by looking at pictures of them. Their responses indicated very literal mental bridges between visual observations and sonic expectations. A room that looked warm was expected to sound warm. A room that was opulently ornamented was expected to sound rich and sumptuous. And so on. To my knoweledge, no formal study has been done ranking the expectation of acoustics based on images, but I'd predict that the Musikverein would come out near the top and the grey room shown below (which is actually supposed to have very good acoustics) would come out near the bottom.

Although the term "Goldener Saal" originally referred to the Musikverein's color, it has come to stand for the room's acoustics. A quick Google search of turns up newspaper headlines like, "Golden sound of Musikverein is music to the ears of Muti, CSO," and "The sound of the Musikverein is pure gold." Language helps to reinforce what would otherwise remain a loose perceptual association.

Beyond the best. What would it take for another hall to knock the Grosser Musikvereinsaal off its pedestal? I don't think its possible. What may be possible, however, is to remove the pedestal entirely, a project I see myself as part of along with a number of other acoustical designers. Over the course of listening to different rooms for music on my Grand Tour, I continue to be surprised by the range of acoustical characters that are out there in the world, many of which I would call excellent but none of which I would crown "the best." Acknowledging and celebrating the variety of acoustical environments is also the foundation of my experiments in acoustical reverse-engineering, a technique that allows designers to shape acoustical signatures and find matching room geometries. But that's another story which I will tell soon.

Program Notes

Grosser Musikvereinsaal, Vienna Monday, Oct. 26 - 11:00 AM Austria National Day Concert

Wiener Johann Strauss Orchester Director: Johannes Widner

Johann Strauss II (1825-1899) Ouvertüre zur Operette “Die Fledermaus” Im Sturmschritt. Polka schnell, op. 348 Wo die Citronen blüh'n. Walzer, op. 364

Josef Strauss (1827-1870) Die Libelle. Polka Mazur, op. 204 For ever. Polka schnell, op. 193 Spärenklänge. Walzer, op. 235

Franz von Suppè (1819-1895) Ouvertüre zur Operette “Banditenstreiche”

Johann Strauss II Bei uns z'Haus. Walzer, op. 361 Melodien-Quadrille, op. 112 Im Krapfenwald'l. Polka française, op. 336 Vergnügungszug. Polka schnell, op. 281 An der schönen blauen Donau. Walzer, op. 314

---

Grosser Musikvereinsaal, Vienna Tuesday, Oct. 27 - 7:30 PM

Cleveland Orchestra Director: Franz Welser-Möst

Olivier Messiaen (1908-1992) L'Ascension. Quatre Méditations symphoniques pour Orchestre. Couleurs de la Cité Céleste

Richard Strauss (1865-1949) Also sprach Zarathustra, op. 3

[fromthesoundup]

(Literally) moving acoustics in the Esterházy Haydnsaal

Thirty-one concerts into my trip, my energy is starting to flag and listening is feeling like more of a chore, especially after a few disappointing experiences, like attending the acoustically ill-preserved Thomaskirche. I have also started to attend operas, which are long and demand constant attention (not to mention constant head-bobbing to read the surtitles). So it was a real relief and a real pleasure to feel a sense of surprise upon hearing the spatially rich sound of the simplest of rooms, the so-called Haydnsaal at Esterházy Palace in Eisenstadt, Austria.

The Haydnsaal is named after Joseph Haydn because it was his primary workplace. Haydn resided in Eisenstadt and worked in the service of the music-loving Esterházy family for 40 years, and it was in this room that he premiered most of his major orchestral works. It was also in this room that the symphony matured as a musical genre.

I did not attend a symphony in the Haydnsaal but a performance of string quartets, one by Haydn and one by Schumann. The program was the finale of a walking concert of the palace that began in the chapel and continued in the banquet room known as the Empiresaal. The acoustics changed dramatically from room to room. The fully-occupied chapel was very live, with a reverberation time well over two seconds, whereas the fully-occupied Empiresaal was very dry, with a reverberation time that can't have been much longer than one second. Accordingly, the clarity was low in chapel and high in the Empiresaal, and vice versa for the blend. The tonal balance in the chapel favored high frequencies, so the violin sounded particularly squeaky and during the Mozart duo overpowered the viola, and the tonal balance in the Empiresaal was more balanced, with a good bass response.

 Enough about these two rooms. It is telling when I never get past basic parameters in my notes—reverberation time, clarity, tonal balance, and so on—that the room is somewhat unremarkable. It's a bit like going on a first date and not getting past the standard icebreakers—where are you from, how long have you been living here, what do you do, what kind of music do you like. The Haydnsaal, unlike the other two rooms, was a good first date, because I didn't think about the basics. The foundation was all there: good reverberation time, good clarity, good tonal balance, good loudness, no echoes. Which left me to revel in the sound's amazing spatial quality.

I began by sitting about halfway back just to the right of the centerline. From this position, the sound was lovely: rich, warm, balanced and surprisingly present given the small size of the ensemble and the large size of the room. (But perhaps it should not have been such a surprise after hearing the similarly present sound of a clarinet, viola and piano trio in the Semperoper [LINK].) The sound was also well-blended and spacious, relieving after the almost-too-intimate acoustics of the Empiresaal exposed every little error the players made. In my notebook, I wrote down the words, "doleful," "gentle" and "consoling" to sum up the acoustics.

At the conclusion of the Haydn quartet, I had the choice of moving forward or moving backward at the room was only a third occupied. Up until this point in the tour, I had been avoiding the front sections of rooms because typically, you hear more of the direct sound and less of the room response close to the stage. But because most of the audience was clustered near the front and I thought I would feel a little lonely surrounded by empty chairs, I decided to move up to a chair about one third of the way back from the stage, as shown in the diagram below.

I am glad I moved where I did because nearer to the stage, the sound acquired a fantastic spatial quality that I have not heard in any other room. As the first movement of the Schumann quartet began, the sound began to unfold around me. It felt like waves of sound were constantly washing over me. Previously, I wrote about [LINK] the experience of seeing bright daylight while listening to the Compenius organ in the Michaeliskirche in Erfurt—in the Haydnsaal, I experienced a similarly synaesthetic experience, except this one was haptic: I felt like I was being gently but completely embraced over and over and over again.

From my new listening position nearer to the front of the Haydnsaal, I found that if I concentrated I could actually trace the path of sound in the room. It started at the front, then broadened to the sides, then rose up above, then swept behind me. The constant spatial movement of sound may sound like it was distracting but it was not—when I relaxed and forgot about the acoustics, I simply enjoyed how it made the music swell and soar.

As soon as arrived in Vienna the next day, I decided to test my hypothesis about the movement of sound in the Haydnsaal by analyzing the "image sources" audible from my listening position. An image source, also known as a virtual source or mirror image, is a term acousticians use to describe the apparent location of a virtual sound source caused by a reflection. When a sound reflects off a surface, what you are hearing is not that surface, but a phantom source a distance behind that surface, just as when you look in a mirror, you don't see your reflected image on the mirror surface per se but somewhere behind the mirror. Unlike looking at multiple copies of yourself in a room full of mirrors, however, image sources in a room for music don't usually sound like multiple copies of the source, but due to a psychological phenomenon known as the precedence effect merge with the source into one sound. If lots of images are audible in front and to the sides of the source, the source will seem enlarged. If a number of images are audible from the sides and behind, the sound should feel enveloping. In theory, it is only when an image becomes audible outside the temporal window of integration that it will separate from the source and sound like a discrete echo.

The diagram above shows what the image source pattern looks like for first, second and third-order specular reflections integrated over 120 milliseconds. There are images to the sides, above and behind, as I heard, but a static image does not tell the whole story.

I decided to animate the image sequence to show when they become audible in the room response, and the result clearly shows the sweeping motion of the sound I heard. The direct sound arrives about 23 ms after the impulse. Images to the sides become audible 22-28 ms later, and are followed by a cluster of images from above and in front, audible from 42 to  72 ms. Then come two images from above and to the sides between 81 and 87 ms. These are quickly followed by reflections from behind, which begin at 91 ms and continue through 120 ms.

My experience of the Haydnsaal's literally moving acoustics makes me wonder if our perception of envelopment is dependent on the order in which reflections arrive from different parts of the room. Sitting further back, I experienced source enlargement and spaciousness but not envelopment, and I wonder if it's because the images were becoming audible closer together in time, with clusters from different directions possibly even overlapping. I will continue to investigate this hypothesis when I get back to New York and hope to write a follow-up post with my findings.

Program notes:

Schloss Esterházy, Eisenstadt Saturday, Oct. 24, 2015 - 7:30 PM

Schumann Quartet

(Schlosskapelle)

W. A. Mozart (1756‒1791) Duo for Violin and Viola in G Major, KV 423

G. Klein (1919-1945) Duo for Violin and Cello (incomplete)

(Empiresaal)

L. van Beethoven (1770‒1827) String Trio in B flat Major, op. 3

(Haydnsaal)

J. Haydn (1732‒1809) String Quartet in D Major, Hob. III:34, op. 20/4

R. Schumann (1810‒1856) String Quartet in a minor, op. 41/1

[fromthesoundup]

Big music in a small room: the Besední Dům

In my last post, I wrote about a small performance in a big space. Now, I will write about a big performance in a small space.

The Besední Dům, or "Meeting House," was built between 1871 and 1873 as a community center for Brno's Czech-speaking population. According to the Brno Philharmonic's website, the main room was used as a multi-purpose center for "social gatherings, music, theater, education, political events, and physical fitness." Over time, music became the primary activity, and today the main room is referred to as a concert hall.

The main room of the Besední Dům closely resembles Vienna's Grösser Musikvereinsaal: it is a long, narrow and tall shoebox with a flat floor and a single wraparound balcony. The proportions of the two rooms are nearly the same, in fact. (The Besední Dům is slightly squatter, but only slightly.) The only significant difference between the two room is the scale: the Besední Dům is a little under two-thirds the length, width and height of the Grösser Musikvereinsaal and about one quarter the volume, as shown below (dimensions are approximate and units are in meters). It is well-known that the Musikverein is a tight squeeze for the orchestra and can get excessively loud when, say, Mahler symphonies are played in it, so I can't imagine how the Brno Philharmonic manages to play late Romantic repertoire in its tiny home without knocking elbows and blowing the audience's (and their own) eardrums out.

I attended a performance of modern and contemporary music in the Besední Dům performed by the Brno Contemporary orchestra. The size of the ensemble grew throughout the night, starting with 15 players, then growing to 22 players, then for the finale swelling to around 35 players (plus tape player), shown below. The sound was indeed very loud, ear-splittingly so in the final piece, but when the orchestra was not playing at full blast, the sound was gorgeous—bright but rich in bass, clear but lush, vastly enlarged but focused, blended but localizable, live but not too reverberant, biting but smooth—with a decay smoother and better-integrated than any I've heard yet on this tour. In a word, the sound was luxurious. And even in the loudest, most dissonant, most painful passages, the sound did not lose its luxuriousness.

It was rather strange, I have to admit, or even inappropriate, to listen to Schoenberg in such a luxurious acoustical environment. I felt myself welling up at one point—I think it may have been one of the few moments of tonal harmony, with the strings all playing a pleasant major triad. But I promptly snapped out of it, reminding myself I should not be feeling mushy: Schoenberg's point, after all, was to break from the mushy sentimentalism of late Romantic music, wasn't it?

The piece by Trevor Grahl, a young Canadian composer who was at the concert (in the blue blazer in the photo below), was intentionally a little sentimental and nostalgic at times, and the acoustics of the hall really highlighted the contrast between these quiet, sweet-sounding bits and the more hard-edged, percussive, and loud passages. Just as the Semperoper in chamber mode can produce different acoustical effects depending on the texture of the music, the Besední Dům can sound gentle or assaulting depending on the dynamics. Of course, the contrast never felt as extreme as the difference between, say, running one's hand over a silk sheet and getting hit in the head with a lead pipe. It was more like the difference between running one's hand over a silk sheet and then getting strangled by it.

The Brno music community is well-aware of how loud their little hall is, and they put the loudness to particularly good use by inviting Canadian veteran noise group Nililist Spasm Band to perform in the Besední Dům as part of the 2014 Brno International Music Festival. A music critic for the Brno Město Hudby newspaper wrote, "Earplugs were offered at the entrance... the Brno Philharmonic attracted and scared the audience by announcing the loudest concert in the history of the Besedni dum." The same critic also notes, however, that, "the sound intensity was bearable and we did not experience the astringent sound pressure that empower you and overclocks your heart." So perhaps even the most aggressive, assaulting music out there cannot escape the Besední Dům's golden embrace!

Program notes:

Besední Dům, Brno Wednesday, Oct. 21 - 7:30 PM

Brno Contemporary Orchestra Director: Pavel Šnajdr

A. Schoenberg (1874‒1951) Chamber Symphony No. 1, Op. 9

Trevor Grahl (1984—) From Curious Lands and Places

Wolfgang Rihm (1952—) Verborgene Forrmen

Alois Piňos (1925‒2008) Concerto for Orchestra And Tape

[fromthesoundup]

Small music in a big room: the Dresden Semperoper in chamber music mode

Despite having the shape of an opera house and being called an opera house, the Dresden Semperoper hosts a much broader range of musical activities than opera alone. It is also home to Dresden's famous symphony orchestra, the Staatskapelle, and to the Semperoper Ballet. I attended two concerts at the Semperoper, one an opera and the other a concert of chamber music played by members of the Staatskapelle. Of the two performances, the chamber music concert has really stuck in my brain because of how surprised I felt at hearing such a small ensemble sound so good in such a large space. Chamber music was originally composed for palace rooms, salons and coffeehouses, not voluminous opera houses. When played in these small rooms, chamber music sounds intimate and enveloping.  The sound I experienced sitting just off center eight rows back from the stage edge was entirely different—it was not particularly intimate and was only lightly enveloping, but it was present and large and spacious, and, as I have already mentioned, so good.

The highlight of the program was a performance of Gyorgy Kurtág's Hommage à Richard Schumann, a haunting and forlorn piece for clarinet, viola and piano made more haunting and forlorn by the spacious acoustics. The piece is made up of several short movements (some only a few seconds long), and is full of melodic, harmonic, rhythmic and dynamic contrasts. The performers attacked the piece's sudden accents and sforzandos with all their energy but never lost their singing tone, even when playing at high, potentially squeaky or squeal-y pitches. One particularly beautiful contrast came when the clarinettist sustained one low note while the violist alternated between pizzicato plucking and spiccato bowing. The clarinet long swell sounded very present and warm, filling the room, while the quick bursts of sound from the viola emphasized the room's size, making the instrument sound more remote. This was only the most memorable among many passages of contrasting instrumental lines, in which the acoustics helped to emphasize the individual lines by adding a spatial dimension of difference to the melodic, harmonic rhythmic and dynamic.  After the piece concluded, the audience was buzzing—I have never hear so much chatter in the middle of a classical music concert. Clearly, I was not the only one who felt moved.

I suspect the Semperoper's spacious sound in chamber music mode is due to two aspects of the room's reflection pattern. First, there are very few surfaces near the center of the stage, so sound has to travel quite far to the room boundaries before reflecting back to the audience. This results in a considerable gap in the room response between the direct sound, reinforced by a single reflection off panels behind the musicians, and the rest of the reflections coming from other parts of the room. From my listening position about halfway back from the stage, the gap was almost but not quite long enough to produce an echo; the reflections were still arriving within the window of integration, so they sounded instead like a soft register of the room's dimensions.

Second, the reflections arrive from multiple directions (the drawing above shows just a few possible paths), making it seem like space extends in all directions. They are not particularly strong reflections compared to those of a small room, so rather than creating a feeling of envelopment and enclosure they again serve as a kind of soft spatial index. In an earlier post, I wrote about how a gap in the room response of the Schwetzingen Jagdsaal resulted in a pretty awful lurching sound. Having heard how lovely the Semperoper sounds with its large gap, I suspect that the lurching I heard in the Jagdsaal may have been more a function of space than a function of time; in the Jagdsaal, all of the reflections arriving immediately after the direct sound came from the front and back while those after the gap came from the sides, whereas in the Semperoper, the reflections come from all around.

I'm pretty sure that the gap in the Semperoper's chamber mode room response is the culprit for the phenomenal spatial contrasts I heard in the Kurtág piece. When an instrument played a long, sustained note, the continuous direct sound masked the reflections, thus also masking the spaciousness of the room. When an instrument played short notes, on the other hand, the gap was exposed, revealing the room's dimensions. Such an effect would not be audible in a better-integrated room.

The singing tone sustained at high volume and high pitch is, I think, largely due to the room's ornamented surfaces, as shown above. The ornament scatters sound at higher frequencies, as shown below, reducing "glare" and giving the sound a slightly darker, more covered tone (ideal for the clarinet in particular). The sound is not muffled, however, again because of the room response gap. The gap allows the bright, full-spectrum direct sound to be highlighted without too much masking from the early reflections.

My experience listening to chamber music in the Semperoper was enlightening, because it revealed that chamber music can sound amazing in very different acoustic environments. It's unlikely of course that anyone will build a room in the shape of an opera house specifically for string quartets but it's interesting to consider how smaller sounds can work well in larger spaces.

Program notes:

Dresden Semperoper Sunday, Oct. 18 - 11:00 AM

Michael Schöch, piano Robert Oberaigner, clarinet Susanne Branny, violin Michael Horwath, viola Titus Maack, cello

R. Schumann (1810-1856) Fantasiestücke for piano an clarinet, op. 73

G. Kurtág (1926—) Hommage à Richard Schumann for clarinet, viola and piano, op. 15d

R. Schumann (1810-1856) Märchenerzählungen for clarinet, viola and piano, op. 132

R. Strauss (1864-1949) Piano quartet in c-minor, op. 13

[fromthesoundup]

Sound trap: the Dresden Neustadt station hall

The entrance hall of the Dresden Neustadt station, constructed between 1898 and 1901, features a visually and acoustically remarkable pendentive dome. The dome is remarkably shallow. When I stood directly under the center, the entire surface appeared to be nearly perpendicular to my line of sight, indicating that my eyes and ears were close to to the center of the sphere the dome follows. 

I clapped and this is what I heard:

Late at night, when the station was quiet except for mechanical noise, the galloping echoes lasted almost nine seconds, as shown below.

The ceiling of the station hall acts as a kind of sound energy trap. Sound emanating from a source (in this case, my hands) reflects off the ceiling and gets focused back down at the source. The sound then reflects off the floor and back up to the dome, and so on and so forth, as shown below.

The echoes brought to mind research on cave acoustics by French musicologist Iegor Reznikoff. Reznikoff found that clapping or drumming in prehistoric caves near certain pictograms of animals produced similar “galloping” sounds among other sound effects. You can read more about Reznikoff’s research here.