I love PromptSmart, but do I need an external mic? If so, which one do I buy?
Nothing is worse than stuff that doesn’t work. We all know that frustration. Save your sanity (and your money) by following this buyer’s guide to help you wade through the sea of options and bewildering tech specs.
In this installment we cover external microphones.
When working with PromptSmart on a mobile device, an external mic can do a lot for you. It ensures that your voice is amplified and picked up by VoiceTrack from distances of up to 20 feet. Without a mic, scrolling accuracy can break down at distances of 5 feet. Speaking from further away is important, however, as it can mitigate pesky eye-tracking so that you don’t look like you’re reading.
A cardioid mic in particular can isolate your voice in a crowded or noisy environment. It’s called a cardioid mic because the pick-up pattern looks like a heart (who knew?). Sound pros use cardioid mics to filter out noise, to attenuate unwanted feedback, and to isolate individual musical instruments during live performances.
Nothing is to stop you from using one out in the field or in a place where you have little to no control over the ambient noise level. Because we want to hear you – and only you. Under the correct conditions, VoiceTrack is accurate, efficient, and will reduce the stress of your filming projects and the time you spend getting a usable take.
Below we’ve offered some tips on how to select the right kind of mic for your project:
(1) Wired lavalier lapel microphone
Simple, reliable, and affordable (can be less than $15 USD) – no latency.
Make sure the cord is long enough for your work space.
Always check compatibility with your mobile device.
Consider investing in an extension cord with the proper TRS > TRRS male/female poles. These cords are fairly common and run ~$13 USD.
What are poles, you ask? The difference between a TRS and a TRRS pole is visible to the naked eye (see below).
(2) 2.4 GHz Wireless Transmitters/Receivers
Declutters work space with fewer wires, but introduces latency;
2.4GHz connection method is not fully reliable;
More expensive than wired mics, but less expensive than pro gear;
Check product specs carefully, as you may need an adapter cable to connect a TRS receiver to your TRRS device (see above).
(3) UHF Wireless Transmitters/Receivers
High quality & professional grade;
Can be very expensive (hundreds of USD);
Most reliable of the wireless connection methods – less latency than 2.4GHz;
Check product specs carefully, as you may need an adapter cable to connect a TRS receiver to your TRRS device
Bluetooth mics are not recommended because they depend on third party software integration; often-changing iOS peer-to-peer permissions; and can introduce substantial latency (i.e., there may be noticeable lag between your speaking and the eventual scrolling). While we intend to support Bluetooth mics and understand the convenience they provide, we still feel compelled to warn users of the pitfalls of that approach.









