PURPOSE: To enable the required speed control with a small amount of data by controlling the stage setting by a manual control part at the preparation stage with the required speed pattern and storing the speed data of the stage setting which is detected in this case, and generating a speed command by making an access to the complement data storage part for each stage setting at the time of performing a playing.

CONSTITUTION: When power devices 11a-11n are controlled individually by manual control parts 13a-13n, the speed of the stage setting to be driven by each power device in a sampling processing part 14 is made sampling by the definite time. The sampling data is temporarily stored in a storage part 15. Then, the special points are extracted by making an access to the storage part 15 in a square deviation complement processing part 16 and the straight line complement and the square deviation arithmetic processing are repeated. Thus, the complement straight line data when the square deviation value is within the prescribed standard value is obtained and it is stored for each stage setting. Then, the complement straight line data of the address corresponding to the stage setting in performing the play is accessed, generating the speed command.