I've got a Vox AC4TV mini guitar amp. It's a 4 watt guitar tube amp with a 6.5 inch speaker... When I play guitar through it I always plug it into an extension cabinet and bypass the tiny internal speaker. I bought it because it's the size of a head and has a speaker just incase I want it... Anyway I rarely play guitar through the internal speaker but would like to see if it could do double duty as a bass practice amp... the stock speaker farts out pretty quick though... Any ideas for a speaker that might work with this and a bass?? car audio maybe?? Thanks.