So I decided to build a power amp for my electric guitar, and through online search I ended up on the LM3886 design at www.generalguitargadgets.com Here is the power amp schematics:

http://www.generalguitargadgets.com/pdf/ggg_lm3886_amp.pdf

The data sheet for the LM3886 states a needed voltage of 28-35V but the PDF asks for a power supply of 18V. Being a complete electronics noob I opted on following the PDF's directions of 18V. Then I needed a 18 bipolar power supply so I found and built this:

http://www.generalguitargadgets.com/pdf/ggg_bipolar_ps.pdf

When I built and connected the whole thing, it only produced a crackling noise, the 7918 regulator of the power supply got EXTREMELY hot (i couldn't even touch the heat sink), and suddenly the 2200uF electrolytic capacitor on the V- end of the amp exploded. Now I know that the capacitor's polarity was correct and it was rated for 26V. And the rest of the caps and resistors are the correct values for the best of my knowledge.

What could have gone wrong? Can you guys please take a look at the PDFs and tell me if they're correct? I'm fairly electronically illiterate but I'm pretty good at following schematics so I don't understand where I've made a mistake. I would appreciate ANY recommendations, corrections, making fun of my noobness etc.

Please help me fix this sucker. Thanx 

Hi everybody, this is my first post here since I'm kinda new new to amp building so please be patient with my noobish questions. So far I am amazed at the depth of knowledge this forum has and so I took the liberty to post my first attempt at amp construction. It is just a Little Gem LM386 amp which I installed in an old PC speaker box I had laying around.

Here it is:


Not much to look at, I know, but it was my first attempt at any electronics build, first attempt at circuit etching, soldering, schematics interpretation, resistor-capacitor readings and all that, and it's working pretty well. So I'm pretty proud and moreover encouraged to build something even better.

So here comes my request for your advise. What would be a good guitar amp for me to build next? This amp was around 1/2- 1watt, with only gain and volume controls. So I am looking for something a little more complex, maybe a couple more control pots, up to maybe 15-20W (if that's too much wattage for a simple build let me know). Also I would greatly appreciate it if there were PCB layouts for it.

I hope I am not asking for too much, please fire away with suggestions, comments, anecdotes etc.