Little Gem MK2
Introduction
This is easy and interesting project from ROG. I needed simple and very clean amp and there were two 386s lying around so I gave it a shot. Also, having only 15×8 holes perfboard in part box I had to squeeze it as much as possible. It drives my 12″ Celestion Greenback very well, also loud enough for bedroom practice. I tried it with two 4″ 5W speakers salvaged from old Genius desktop speaker set but it sounds terrible, fizzy distorted sound all the time. I needed only clean amp so nothing is connected between pins 1 and 8 (gain control) of 386s for cleanest sound possible. There aren’t any pots or switches, volume and tone are controlled only with guitar pots. There’s no need for them because it will mostly be used as power amp only together with my Tube Reactor preamp.
Pictorial
Click on a photo to see more details
Update: I’ve heard that those 386D ICs can get warm so I placed heat sink salvaged from an old graphic card.
Update: Since I really like this amp I tried to further improve it by shielding enclosure. I got a decent sized self adhesive copper tape for my guitar project, so lot’s of it left over for other projects like this. It is clean amp, so there isn’t noise anyway, but it might help if used with hi-gain pedal. And I also got rid of that silly tape holding that matte plastic
Clips
Considering how simple and cheap it is, it sounds pretty good. I’m not a fan of distorted sounds, as it clips kinda raspy. As long as you don’t overdrive it, clean sounds are nice. Below is a clip I recorded with my Ibanez and Mini LP. Ibanez goes first then Mini LP. The last bit is played with the IIc+ preamp making all the distortion, all others are guitar straight into the Little Gem.
Useful links
RunOffGroove.com project article


Hi Bane,
I’m really interested in building a guitar amp myself. However I can’t get grip on some facts. This amp you’ve build here seems like a nice first attempt for me to recreate it.
Some questions I have:
I plug my guitar into the ”in” and simply connect a (descent) speaker to the out?
Can you mail me de schematics of this amp and/or send me pictures or drawings of the layout and the wiring?
Do I have to consider any about using/making this?
Kind regards,
Ron
Also, the components