Ruby Amp PCB – Build your own guitar Amplifier


This tiny footprint board hangs from the 2 pots, can power a 2×12 cab and can fit in a 1590Q box – you know you want it!

NEW – Interactive B.O.M Helper

We include a standalone HTML file with each of our boards that helps show you what parts go where (find it in the “Build Docs & Extra Info” Tab)- just extract the zip file to a folder and open the .html file in your internet browser. You can use the table on the left to tick off the parts as you source them / add them to the board – we found its a very handy and a big shout out to Interactive HTML BOM Plugin which is a free plugin on GitHub used to generate these.

The Ruby Amp from Five Cats Pedals is an LM386 based guitar amplifier board. It is an enhanced version of the previous Little Gem Amp designed by Runoffgroove. The main improvements of the Ruby Amp vs the Little Gem are new the input buffer, a volume control, and an updated Gain potentiometer. The board mounts vertically from the pots and fits in a 1590B perfectly - but you could put it in any box you wanted!

These tiny little amp's can drive some surprisingly big speaker cabs! You can wire it to run from a 9v battery or the usual negative center 9v mains (we suggest the mains!).

You'll get a full colour build guide with your purchase, but please remember you are buying JUST THE BOARD and you have to source your own components.

Ruby Amp Wiring - Five Cats Pedals

Wiring diagram - click to enlarge








If you want to add a power toggle and LED - we've made a guide for you which can be found here

Additional information

Fits Enclosure: 1590B
Build Docs Ruby Amp -V1.1 – Build Docs
Interactive B.O.M Ruby-Amp-V1.1 – Interactive B.O.M (.zip download)
Schematic Ruby Amp - V1.1 - Schematic
General Build Guide Five Cats Pedals - General Build Guide V1.0