Reverb tank

The sprung metal reverb unit inside a traditional guitar amplifier, in which a signal is sent through springs and picked up again at the far end.

The springs twist in response to the signal, and a transducer at the other end converts that movement back into sound, producing the distinctive boomy, slightly metallic echo that players recognise as spring reverb. Because the springs are physical, the tank is sensitive to knocks, which is why a bumped amplifier makes a crashing noise, and why long cables to and from the tank need screening. Physical size and the number of springs affect how long and how dense the reverb sounds.

Example: a short, bright spring reverb is the sound that gives a surf guitar its splashy, dripping character.

Reverb tank

See also