STAX SRM-D10 II – portable electrostatic headphone amplifier and USB DAC

The STAX SRM-D10 II is a battery-powered electrostatic headphone amplifier designed for listeners and audio professionals who want to use compatible STAX Earspeakers beyond a conventional full-size system. Combining a dedicated high-voltage driver stage with an integrated USB DAC, it provides a space-efficient option for desktop listening, travel setups and professional workstations. Its compact format is particularly useful for existing STAX owners seeking a second amplifier for another room or location, while the choice of digital and analogue inputs allows it to work with a broad selection of suitable computers, portable players and audio components.

Digital conversion is handled by an AKM4493 DAC chip with hardware decoding. The SRM-D10 II accepts PCM audio at resolutions up to 384 kHz/32-bit and supports DSD playback up to DSD256, enabling direct use with many commonly available high-resolution music libraries. Its amplifier section and selected audio capacitors are intended to maintain clarity, low-level detail and stable presentation rather than applying an exaggerated tonal effect. A 580 V DC PRO bias supplies the operating voltage required by compatible STAX PRO-type Earspeakers. The aluminium-alloy enclosure adds structural strength and corrosion resistance while keeping the design compact and suitable for regular transport.

A USB-C 3.0 connection handles both digital audio input and internal battery charging, reducing the number of different connections required in a portable system. A separate 3.5 mm analogue input makes it possible to use an external DAC, portable music player or another source with an appropriate line-level output. For reliable operation, keep the ventilation and connectors clean, avoid exposure to moisture and excessive heat, and use a well-made USB cable when playing high-resolution files. The listed one-year limited warranty applies to the United States, so buyers in other markets should confirm local coverage with their retailer. Consider the STAX SRM-D10 II when you need a compact and versatile way to power your PRO-type Earspeakers.