PURPOSE: To provide a tape recorder of simple and small size constitution and prevent unnecessary power consumption by connecting an adapter provided with a high voltage large capacity power source, etc. for motor driving, etc. and putting the tape recorder in an operating state.

CONSTITUTION: When a variable speech control adapter 22 is connected to a tape recorder 26 provided with a low voltage large capacity power source 42, etc. for driving a preamplifier 37, output amplifier 38, motor current, speed control circuits 39, 40, etc., then turning of the motor 36 of the tape recorder 26 of the speed according to a variable resistance 45 via reproduction equalizer 46, pitch conversion circuit 47, motor speed control circuit 48, etc. and controlling of pitch by the circuits 46, 47 are accomplished by the high voltage large capacity power source 25 of the adapter 22 and the reproduction sound corresponding to the tape speed is produced from a speaker. This minimum required simple constitution of the tape recorder miniaturizes the tape recorder and prevents unnecessary power consumption through operation only when the adapter is connected.