I have just started experimenting with a Electro Harmonix Caliber 22 amplifier. It's the size of a stompbox and puts out 22 watts of power. Plugged into a whizzy 10 it sounds not too bad. When I run it into my dtar equinox parametric preamp and then to the whizzy it sounds simply sweet. I know most of you think that 22 watts is not even worth talking about, but it will absolutely bury 2 or 3 loud acoustic guitars so it's fine for practice, acoustic jamming and small coffee house type gigs. really convenient as well. fits right into the whizzy 10 carry bag along with its power supply (the power supply is roughly the same size as the amp) However I must be honest and say that it does not sound as good as my ampeg b12!!!