I'm new to amp building, made a couple of LM386 set ups running on batteries, a muff pi, and a simple crappy tone killing fuzz effect.  I recently got 10 TDA2003 chips for fun ($8)

I built the simple amplifier circuit from the datasheet and had it sounded like garbage.  Would hum really bad with nothing hooked up, wasn't very loud.  If i cranked my guitar to max volume, it would cut out all together.

This was powered off the 12v lines of a computer power supply.  I also(for giggles) hooked a 9 volt to it. <-- same results with the 9volt just not as loud.

My intended use is to build a battery powered amp.  I've got me a nice little 12v 7amp security battery with a regulator/charger that will push a steady 12v at 3 amps max.



my lm386 builds are louder than this thing is currently, they also have more clean head room than this does (NONE)... So I'm doing something wrong.

Where should i start?