Namely, if the tone color information comprises such data as shown in FIGS. 9A to 9C, this means that the plug-in board 2 attached to the first slot (DN=1) possesses tone colors of program changes ???0???, ???2??? and ???5??? for bank number ???0???, tone color of program change ???2??? for bank number ???1??? and tone color of program change ???0??? for bank number ???2??? but does not support an