Electronic vibrato or celeste

Abstract

Electronic circuits are provided for producing an electronic timbre modulation for effecting celeste or vibrato similar in sonic results to the well-known Leslie rotating speaker system. Electronic signals corresponding to audio tones are generated and are modified by appropriate filters. Three controlling oscillators are locked in exactly 120° phase relation to one another and act through three voltage controlled oscillators respectively to modulate three bucket brigade circuits through which said modified electronic signals are passed substantially in parallel. A roving band pass filter further modulates those of said electronic signals corresponding to flute tones to simulate other aspects of a Leslie speaker system.