The amp was made in the early '90s using Ampegs Super Valve Technology. It runs on 3x12AX7 valves (Hot Rods in mine) and these valves are enough to support any style of music, when teamed up with the amps graphic EQ and mid-range selector, allowing you as the bassist to choose where the amp's reference point is when adjusting the mids knob. It is only a single channel amplifier, but the Graphic EQ is footswitchable allowing you to boost EQ or completely change it, ie: during bass solos. It has an FX loop on the rear of the rear of the amp, and a wireless input also on the back. This is there so that when using a rackmount wireless reciever, the SVT-III (also rackmount) can be connected to it with the cables staying in the rear of the rack. This input, however, is still connected to all of the EQ etc. so that it works just like the input on the front. It has jack and XLR line outs on the back with a line out volume control on it, so that it can be connected to a PA / Recording Interface as a DI device. This DI feature also works when speakers are connected. There is no headphone connection, but if you disconnect the speaker jacks, headphones work in the line out socket. There are 3 speaker outputs on it, 2 are jack connections

Ampeg SVT-III Bass Head