Control panel from left to right after the Fuse holder, Off-on switch, Standby-on switch, Indicator, Brightness, Bass, Middle, Treble, Volume I and associated input jack sockets (Guitar channel), Volume II and input jacks (Bass channel). On lead guitar with a four by twelve cab sounds excellent especially when cranked up on the volume. Also sounds great on bass especially when one of the bass input jacks is linked via a patch lead to one of the guitar input jack sockets. Plug the bass guitar into the remaining bass input jack and adjust volume 1 and volume 2 for optimum mix via the patch lead. Currently fitted with a set of four matched Tesla EL34 output valves. This amp also sounds great on bass guitar.