As you can see in the schematic below there s a lot going on inside that eight pin dip chip.
Ruby amp vero layout.
Simple dual led battery monitor stripboard layout.
The architecture of the little gem has been updated with an input buffer as found in the little gem mkii feeding the inverting input and the volume control changed from the output rheostat to the type and placement as shown in the datasheet application notes.
It is a popular choice for low powered guitar amplifiers due to its low quiescent current and ability to run on 9v.
I have just verified this.
Maybe overkill but i have made almost every 386 amplifier on the internet.
I was pleasantly surprised about how easy it was to use the software and i may well consider using it again in the future.
The lm386 is a specialized op amp that was designed for easy creation of various audio amplifiers.
So it s good to go.
The data sheet for all 78xx v r s suggest using two fairly large caps for the in and out to ground.
Verified ish the gain wires need to be switched around.
The ruby amp is an lm386 based guitar amplifier.
I just built the noisy cricket based on the ruby amp and wired it straight into a strandard 8ohm 8 midrange speaker and it worked just fine.
It might be helpful to add a daughter board to the layout.
Also added a very small heat sink.
Ruby is an enhanced version of the little gem battery powered amplifier.
It has been used in a lot of popular amps like the smokey amp the little gem the ruby amp the marshall ms 2 and the noisy cricket.
I used a demo version of lochmaster to layout a version of the lm386 ruby amp.
Ruby amplifier stripboard layout.
Although they are correct according to the schem.
The main power amplifier stage is based on the lm386 audio integrated amplifier.
The lm386 chip amplifier.
The 1 lm386 chip amp does all the amplification in the ruby amp.
It is an enhanced version of the previous little gem amp also designed by runoffgroove.
The main improvements of the ruby amp vs the little gem are new the input buffer a renovated volume control and an updated gain potentiometer.
I don t think it s too fussy about what you use i ve seen people use the tiny 1 mylar speakers or hook them up to 4 x 12 marshall cabinets.