Sequential drum
M. V. Mathews · The Journal of the Acoustical Society of America · 1979
A sequential drum is described. It consists of a square surface 20″ by 20″ which is hit with conventional drum sticks. Transducers on the surface generate three electric signals each time the surface is hit. One signal is a pulse whose amplitude is proportional to the impact. The other two signals encode the x and y positions of the stroke. The three signals are transmitted to a digital sound synthesizer (Alles machine) which generates a note each time a signal is received. The loudness of the sound is controlled by the amplitude pulse. The timbre of the sound is controlled by the x and y signals. The pitch of the sound is obtained from a score stored in the memory of the digital synthesizer. Each time the drum is struck, the next pitch in the score is played; thus, the desired sequence of pitches is produced automatically by the instrument.