PURPOSE: To obtain the timbre control unit of the electronic musical instrument which automatically and easily varies the atmosphere of the whole timbre even with the same musical signal by varying the timbre according to the characteristics and output level of a speaker.

CONSTITUTION: An inputted input sound signal is sent to a sound source under the control of a CPU 10 to generate a musical sound. The read part 11 of the CPU 10 receives this signal, retrieves a timbre setting table 12 on a ROM 4 to find a timbre control signal corresponding to the set value of an operation element 1, and sends the timbre control signal to respective scalers 7a, 7b, and 7c. Multipliers 16a, 16b, and 16c receives the musical sound signal from the sound source 6, converts the output level of the musical sound signal on the basis of control values sent from the respective scalers 7a, 7b, and 7c, and converts it into an analog signal by a D/A converter 17; and amplifiers 8a, 8b, and 8c provided by speakers 9a, 9b, and 9c having different frequency characteristics amplify the signal to specific gains and sends the resulting signals to the speakers 9a, 9b, and 9c. Consequently, the speakers 9a, 9b, and 9c output sounds with desired timbres.