Abstract: An electronic circuit for simulating the sound of a skin head percussive instrument struck with a stick includes a pair of ringing oscillators of different frequencies both triggered by pulses from the rhythm pattern generator of an electronic organ, a circuit for combining the output signals from the two ringing oscillators in preselected amplitude proportions, and a circuit for distorting the combined signal in such a way as to non-linearly amplify the combined signal so as to produce an electrical signal having characteristics such that when acoustically reproduced produces a sound highly simulative of that produced when the membrane of a skin head instrument is struck with a stick.

Abstract: An electronic musical circuit simulates the sound of a wire brush rotated around the head of a snare drum by differently amplitude modulating and bandpass filtering in separate channels a noise signal derived from a suitable source and summing the modulated and filtered noise signals from the separate channels to produce a sound imitative of the rhythmic variations in pitch and amplitude produced by wire brush rotation on the head of a snare drum.