Roland BTY-NIMH/A

This battery is so useful for this amp - it saves carrying endless AA batteries, it lasts longer, and gives the amp slightly more volume. Four stars for two reasons:

1- this is my second battery of this kind, the first one was used heavily and batteries degrade, and eventually it stopped charging after almost three years of use, but it’s good, so repeat purchase.

2- one niggle is you can’t charge the battery and use it to power the amp simultaneously. It uses the amps power cord, so unless you have a backup set of AAs (or a second Roland adapter for the amp), you can’t charge the battery while also using the amp.

Overall this improves the amplifier (Roland Street Cube EX but I believe comparable with other Roland and Boss amps) and lasts longer than using AAs. It charges pretty quickly and I reckon you get at least 18 hours out of it (I think they quote 20 hours), so with charging in between use, it’s great. The amp puts out good power with it in use, comparable to plugged in to an outlet.