Originally Posted by seamonkey
Best bet is to get a Class-D Car power amplifier...
Ive tried the inverter method, but those things put out a square wave
. Every amp i plugged into it had nasty 60 Hz buzz. Grounding the unit helped with the noise somewhat, but still pretty bad.
Im getting a class-D car power amp for busking.
Edit: The unit that B-string linked to has a "modified sine wave" output. Mine does not. Maybe the Cobra inverter is not noisy.