Precision Motor

About the Precision Motor

The Walker Audio Precision Motor Controller (PMC) is a Variable Frequency Drive (VFD) that uses an XR2206 function generator IC to produce a sinewave signal for driving 120VAC synchronous motors in turntables. It supports nominal speeds of 33 and 45 RPM, selectable via a front panel switch, with recessed analog adjustments for fine tuning each speed. The unit includes a phase reversal switch to accommodate motor winding differences and reduce cogging effects, improving motor smoothness and speed stability. The PMC is housed in a heavy folded steel case with epoxy powder coating and features a heatsink on the side. It accepts 120VAC input via an IEC C13 socket and delivers up to 15W output power. The output voltage is fixed internally, and the device uses 60 Hz for 33 RPM and 81 Hz for 45 RPM operation. The controller reduces electrical noise and speed drift, resulting in a more stable and transparent analog playback experience. It is designed for turntables with AC synchronous motors and does not support 50Hz motors. The unit weighs approximately 10.25 lbs and measures 8"W x 17.5"L x 3.5"H. The PMC improves soundstage depth, dynamics, and bass definition by providing clean, stable power to the motor and isolating motor noise from other audio components.