Nov 30, 2016
Making a DC-blocking/AC-coupling cable
Solder a 0.1µF cap in series with an audio plug's tip (I used this cap). Make sure to use a bit of heat shrink to insulate the signal from ground. Close it up, and you're done. Used with a 100k input impedance (the Eurorack pseudo-standard), this creates a high-pass filter with a -3dB point at 16Hz. Blocks the DC component of any signal. I made this to feed AC-only signals to ring modulators – but it could also be useful for other applications, as well as for troubleshooting.