batteryACID is a simple yet elegant distortion module for analogue synthesis. It is based on the infamous MXR Distortion+ and is great for acid basslines and other uses. Try running drums and other timbres through the unit for cool effects! It is very easy to build and is quite forgiving in terms of component selection. It requires only a positive supply voltage. Anything from 5V to 15V will work fine, so it is a great candidate to build into a portable unit and run off of a 9V battery.