Chorus is the most commonly used effect on electric piano sounds. The Vintage Electric Piano Chorus effect is based on a delay circuit. The delay time is modulated by an LFO. The delayed effect signal is mixed with the original signal.
On/off button: Turn the Chorus effect on or off.
Rate knob and field: Set the speed of the Chorus effect, in Hz. High values may result in the piano sounding detuned.
Intensity knob and field: Set the intensity of the Chorus effect. Technically, this sets the amount of delay time deviation.