portable fiddle amp test

So I need to be able to play loudly and to be totally moveable (as in walk around a town, for hours, not just a few feet) so all battery operated high powered amps like the fender cube are no good for me
I have to play against 2 accordions and percussion (at least)
and be heard
so this is what I'm working on
though I've had a few troubles with strings and pegs on old violins! arghhh! long story
anyway.. this is a test
(ps I've been converted string wise!)
love the D'addarios