Designing mini amp amp

[kin0]

Hay, I want to design my own mini amp (I mean about 1/2 to 1 watt like the smokey). I know I can use the little gem/ruby/smokey but I want to make a lot of them and sell them so I prefer my own design. I want it to work on 9V battery. Do anyone have suggestions? Oh and sources of info will be good too.

[rowdy_riemer]

I really like the way my ruby and little gem MkII sound with a tone stack and booster in front of them. Maybe you could try combining such things into one amp. Maybe combine the tonemender (see ROG) and the ruby or little gem.

[kin0]

Okay. But will the battery (9V) last long enough? Also I am afraid it's illegal to use this designs for commercial use.

[rowdy_riemer]

Actually, I really do not think it is. ROG probably want's a license fee for using their designs, but they are not patented. (Still, it would be damn nice to send them a cut of your sales if you use their designs.) Also, there's really not that much difference between their ruby/little gem designs and the reference design in the data sheet for the lm386. You can use the reference design as a starting point. Use a little different tone stack. Or maybe a very different tone stack. The real mojo in the lm386 designs comes from how the lm386 sounds when overdriven.

[J M Fahey]

If you use the circuit suggested by the chip manufacturer , you will have no legal problem.
They designed it and still hold the copyright, but they *want* you (or anybody) to use it, because you will buy their chip.
The Smokey is a *simplified* version of that; you can use the full one (6 parts instead of 3, big deal).
Same applies to all other datasheet schematics.