An electronic musical instrument has a generator assigner (2) for supplying note data and octave data by key stroke, a top octave synthesizer (3) for generating 12 highest pitch signals for each note, a circuit (5) for selecting one highest pitch signal from the 12 highest pitch signals according to note data, a binary counter (6) for dividing said highest pitch signal to produce several pitch signals, and circuits (7) for selecting one pitch signal out of several pitch signals obtained by the binary counter. Further circuits (10) are controlled by both octave data and note data to generate octave series tone signals and non octave series tone signals such as quint series tone signals.