Passive Filter


This is a passive low-pass filter with volume control. With a 1/4″ mono input on the left and output on the right it is simple way to add control to devices that may be lacking.

The circuit is the same used in other devices like the Minimal Drone and Auto-Step Synthesizer. Since it is completely passive it requires no external power.

It is housed in a very snug yet extremely tough die-cast aluminum enclosure.

Free shipping in the US. Outside the US is $12 for the first item and $8 for each additional item.

Ships next day.

In stock



Here is an example running a Casio keyboard through it….