Solid State Guitar Amp Forum | DIY Guitar Amplifiers
Solid State Amplifiers => The Newcomer's Forum => Topic started by: Leopard on May 11, 2009, 01:39:47 PM
Hi all,
I just made this simple LM386-schematic, and would like to get some suggestions etc. regarding it. It is sort of based on the Little Gem / Ruby plus common sense, so nothing original here, just a cost-cutting variation. All feedback is welcome! :)
And a couple of questions:
1. Pin 7 is bypass, do I have to connect it to ground or can I just leave it open? Additionally, in the Ruby schematic, theres a 100nF cap before ground, what does it do?
2. What do I benefit if I added a 47nF input cap?
3. What are the 10ohm resistor + 47nF cap after output pin 5 for in the Ruby schematic? Noise filtering?
(http://img79.imageshack.us/img79/9139/ampa.png) (http://img79.imageshack.us/img79/9139/ampa.png)
Hi Leopard.
Sorry but it has a couple mistakes, correcting them sends us back to square one.
Just stick to the original schematic that´s simple and cheap enough , or even better, build one and post your results. Some photos or MP3s won´t hurt either.
Thanks.
Whoops! I accidentally put the power supply filtering cap like that... It should be tied to ground instead of being in the power supply path, right?
Also, the 10K volume pot should also be grounded. Output @ pin 5 should also have a ground connection before the electrolytic cap? Any more mistakes? :)