Cigar Box Amp
After months of looking around the local guitar shops looking for something cheap that I could plug my guitar into and listen through walkman style headphones and finding nothing, I decided to attempt building my own.
After a little effort and experimenting I finally built a low noise amp that works wonderfully. This amplifier is driven by one 9 volt battery. The op amp is a LM386. The gain with this configuration is 200.
I have checked this diagram carefully. It is correct.
Components (minus the headphones) only cost me $15.00 at my local Radio Shack.
You do not have to an electronics expert to build this. I have no real electronics experience and was able to hack this together. Must be heard to be believed.
You could build this on a little perfboard and actually fit this into your guitars body cavity.
IT WORKS FOR ACTIVE AND PASSIVE PICKUP ARRANGEMENTS
1/4 ” Jack for guitar signal input
Head phone jack (stereo connect left and right channel)
1 9 volt battery terminal connector and 9 volt battery
Capacitors one each: 10uF, 220uF, 0.1uF
1 10 ohm resistor
1 LM386 op amp
8 pin IC base (optional, I used one because I did not want to burn up the IC)
SPST switch (optional, I used one so that the battery would last longer)
Perfboard of choice.
You can go gonzo with different boxes (I used a cigar box for the first one that I built) or you can fit it into the cavity in your guitar (I used velcro to keep the battery from flopping around) or you can add LED bar graphs (I don’t know the number for the control chip) etc. Your taste and equipment are the only real guidelines here if the above instructions are followed it doesn’t take online degrees to to take your cigar box amp to the next level.