Pedal resonance effect simulation device for digital pianos
Giovanni De Poli · The Journal of the Acoustical Society of America · 1998
Acoustical pianos usually have a pedal which lifts the dampers from the bass strings to provide through sympathetic vibration a reverberant tonal effect for the tones produced in the middle and treble portions of the scale. The purpose of this patent is to disclose means for producing a similar effect for digital electronic pianos. The microprocessor circuitry uses delay lines to simulate the first 18 strings in the scale and activates them when the pedal is pressed, deactivating them when the pedal is released.