I'd agree with Jazzyvee that the Phil Jones Briefcase is a great amp that can work off a battery that provides clean sound and plenty of volume. It is a bit heavy, however, weighing in at a little under 30 lbs. (the Bass Cub in comparison is less than half the weight of the Briefcase but alas has no battery option). The one I have has Piranha speakers in it as opposed to the Neo speakers now available in most PJB products. As a result it doesn't have quite as warm a tone. The battery is rechargable, but don't believe the hype that it will get you 20 hours without recharging. Mine started out providing 13-14 but has recently dropped to 10 (not that I ever see myself playing for 10 hours straight). I do have to admit that I really like the PJB cabs and typically play through a 6B/9B combi. Some people don't appreciate the sound anywhere near as much as I do.