STAX SRM-D50 electrostatic driver and DAC for streamlined listening

The STAX SRM-D50 is a high-performance electrostatic driver with a built-in digital-to-analogue converter, created for listeners who want a tidy and versatile way to operate compatible STAX earspeakers. Inspired by the battery-powered SRM-D10, the SRM-D50 translates the convenient integrated concept into a mains-powered component for a permanent desktop or dedicated headphone system. Combining digital conversion and electrostatic drive circuitry in one enclosure reduces the need for a separate DAC and helps simplify system layout. It is a practical choice for music lovers using computers, digital transports, network players or conventional analogue sources.

Its digital connection panel includes USB Type B, TOSLINK optical and coaxial RCA inputs, allowing several common source types to remain connected. The internal DAC accepts high-resolution PCM material up to 32-bit/384 kHz and DSD up to 5.6, while the analogue RCA input enables use with an external converter or another line-level component. A front-mounted VU meter provides a visible indication of incoming signal strength. Construction details include a 4 mm thick non-magnetic aluminium cover and an R-core power transformer designed with reduced leakage flux. Together, these features support a compact component that feels substantial while retaining straightforward operation.

The specified frequency response extends from 20 Hz to 40 kHz within ±3 dB, with 59 dB of gain and a maximum output voltage of 400 V RMS or 1130 V peak-to-peak. The SRM-D50 operates with a DC 580 V bias, and harmonic distortion is rated at 0.025% or less from 1 kHz to 10 kHz when used with the STAX SR-L series. Measuring 192 × 67 × 268 mm and weighing 4.5 kg, it can fit comfortably into a focused desktop system or a compact equipment rack. Keep the ventilation openings clear and operate the unit within the specified 0 to 35 °C range. As this version is rated for AC 110 V/60 Hz, confirm local mains compatibility before purchase and consider the SRM-D50 for a clean, integrated STAX setup.