the vesta kaza rv-3 is a dual spring reverb unit.

the rv-3 offers two independent channels and can therefore be used as two mono reverbs or as one stereo reverb. each channel is equiped with identical controls: input level, output level, dry/wet mix, 3x eq gain (100 hz, 800 hz, 6000 hz). each channel also incorporates an automatic limiter to prevent excessive signal overload. the rv-3 lacks a feedback control, but the other features make up for it. obviously the equalizer is an effective tool for manipulating the sound of the reverb.

the general problem with spring reverbs is that the springs have a fixed reverb time, determined by the length of the springs. also the sound range of a spring reverb is very limited, so you probably want to shape the reverb sound afterwards. the rv-3 can shape the reverb sound internally with the equalizers, which greatly adds to the flexibility of the device.