Voltage Controlled Low-Pass Filter

Thread Starter


Joined Jan 13, 2008
Hi all. I am currently doing a project that needs a very simple, low-pass filter for audio. I have successfully integrated this low pass filter I found online.

Now the only problem is that I need to be able to control the cutoff with a variable voltage I have. Does anyone know how I can modify this circuit to achieve this?

I've found many voltage controlled filter schematics online but they either didn't work at my voltage (single supply 9v) or they were too complicated/required too many components. So if you know if a simple way to integrate this into the circuit I have here that would be ideal for me.