Sony ULT Field 1

A bass-forward mid-size speaker built to be knocked around. Sony rates the ULT Field 1 IP67 and shockproof, with the seal counting only when the port cap is closed, and its detachable strap lets it hang from a tent loop or a tree branch. The ULT button adds bass on demand, the rated battery is 12 hours, and two of them pair for stereo. At about 2 pounds it sits between the Flip 7 and the bigger boxes, at around $138.