A plate reverb unit is constructed in the following way: Electrical signal carrying the sound is sent to a metal plate through a transducer similar to a speaker driver. The metal plate vibrates with the sound and then has residual "echo" vibrations. Another transducer – one similar to a guitar pickup – picks up the vibrations of the plate and converts them into an electric signal. Since this second transducer picks up also the residual "echo" vibrations of the plate the end result is a reverberated sound.
Plate reverb is reverb simulated by using an output transducer to pick up the residual vibrations of a metal plate after initial vibrations in the plate are generated by an input transducer.
A plate reverb unit works similarly to a spring reverb unit except that it uses a metal plate instead of springs.
Properties and use of the plate reverb
The plate reverb exhibits specific qualities because of its construction. It has large diffusion (i.e., many repetitions) and a specific coloration – it accentuates frequencies above 2 KHz creating a notable sibilance and shimmer. Digital reverbs that imitate the plate reverb aim for the same qualities: many repetitions and a boost to high frequencies. Because of these qualities, plate reverbs tend to be used more on vocals and drums.