1Wamp is a one Watt small guitar amplifier based on a JFET guitar pre-amp, the Big Muff Pi tone control, and the LM386 power amplifier. This portable amp is an open hardware project designed by ElectroSmash using only free / open-source tools.
The preamp stage with two J201 transistors is designed to give a tube-like sound, the BMP tone stage is able to produce a big range of tones and the LM386 output stage can drive any kind of speaker, from headphones to a Marshall 2x12 cabinet.
