Tremolo cavity

The routed recess in the back of the body that houses the tremolo block, springs and claw.

The spring cavity is what allows a tremolo to move at all, since the block needs somewhere to swing when the arm is used. It is also one of the reasons tremolo-equipped guitars sound different from hardtail versions of the same model: removing that much wood, and adding an open chamber, changes the resonance of the whole instrument. On some designs the cavity is open at the back under a plastic cover, and on others it is closed by a back plate.

Example: Removing the plastic cover on the back of a tremolo guitar reveals the tremolo cavity and its springs.

Tremolo cavity

See also