PURPOSE: To allow the scrupulous variable control of the characteristics of the musical tones generated successively with lapse of time by successively subjecting the characteristics of the musical tones already generated in accordance with 2nd response data to the variable control.

CONSTITUTION: Musical tone signals are formed by adding pitch, sound volume and timbre to the musical tones generated according to the pitch data corresponding to a KEY SW2 pushed by a player and the initial data corresponding to the player's way of blowing in the beginning of blowing on a sound source 4 side. The AD data after a sample (N+2) are successively sampled in order to form after-data and the values of the respective samples are converted to sound volume data, etc. The change of the detection signal with time is successively reflected in the characteristics of the generated musical tones in this way according to the changing state of the detection signal with time.