Pioneer MU-31D
¥ 18,500 (around 1972)
Commentary
Belt drive phono motor with hysteresis synchronous outer rotor motor.
Uses a 4-pole hysteresis synchronous outer rotor type motor with large torque and enhanced durability.
An aluminum alloy die-cast turntable is used for the turntable.
A Center shaft side pressure prevention mechanism is adopted. A pulley is placed in the opposite direction of the capstan, and a belt is also placed on it to prevent side pressure to the shaft. This is a unique mechanism.
Equipped with a button lock function, it has a safety design so that the rotation speed cannot be changed when the motor stops.
This prevents the belt from hurting.
Model Rating
Type | Phono motor |
Motor | 4-pole hysteresis synchronous outer rotor type |
Drive system | Belt drive |
Turntable | 30 cm Diameter Aluminum Alloy Die-cast (1.3 kg) |
Number of revolutions | 33 1/3, 45 rpm |
Uneven rotation | 0.1% or less (WRMS) |
S/N | 50 dB or more |
Attachment mechanism | Push-button speed selector Center shaft side pressure relief mechanism Belt protection device |
External dimensions | Width 335x Height 109x Depth 325 mm |
Weight | 3.9kg |