I have just bought myself a Kala U-Bass. It is a bass ukulele based on a Baritone uke body but modified to take special strings so it plays at the same pitch as an upright bass or bass guitar.

More Information here

Mine is a solid mahogany body but with a passive piezo pickup rather than the active pickup shown in the link. It is OK but quiet played acoustically but really needs an amp to bring out the best.

I am looking for suggestions for a small bass amp - preferably battery operated - about 15 - 20W output and physically small as I don't have a lot of room to store it. I tried it through a 15W amp in the shop and there was adequate volume and it sounded really good.

I will mainly be using it as a bass in an otherwise acoustic band, so definitely don't need a large amp.

Suggestions please.