Abstract: An automatic electronic musical instrument generates structured and pleasing musical sound patterns from a random sequence. One phase of the random sequence is supplied to a first shift register. A first plurality of outputs from the first shift register is used to control a rhythm oscillator. A second plurality of outputs from the first shift register is used to control a pitch oscillator. A second shift register receives a second phase of the random sequence and the rhythm signal produced by the rhythm oscillator. A programmed control input provides a song structure to the outputs of the second shift register. The outputs of the second shift register are supplied as inputs to a musical frequency generating means which has the capability of transforming dissonant frequency combinations otherwise selected by those inputs to compatible frequency combinations. The musical frequency generating means also receives the pitch signal from the pitch oscillator.