I'm looking for a power amp, but I don't want a great big lump of a thing. I've run my Ampeg preamp into the effects return of a Markbass 250 and it sounded fine (for a bit more power I'll try it into my 500W Markbass next time I have a go). Are there any compact, lightweight, gig-worthy power amps available?   (I suppose if I get to playing stadiums, I might want something a bit more hefty, but then again (a) that's unlikely and (b) it'd all be going via the PA anyway.)