The SMSL SU-3 combines AK4496 conversion with 32-band parametric EQ

The SMSL SU-3 is a compact desktop digital-to-analog converter using an AKM AK4496 DAC and XMOS XU-316 USB interface. It supports PCM playback up to 32-bit/768 kHz and native DSD512 over USB, with balanced XLR and single-ended RCA outputs for connection to amplifiers, powered speakers, and other line-level equipment. A 32-band parametric EQ provides detailed frequency-response adjustment, while dual low-phase-noise femtosecond crystal oscillators and a dedicated USB power-filtering stage address clocking and incoming power noise within a chassis measuring 4.57 x 1.57 x 3.43 in (116 x 40 x 87 mm).

XMOS USB audio with PCM 768 kHz and DSD512 support

An XMOS XU-316 controller handles asynchronous USB audio. PCM support extends from 44.1 kHz through 768 kHz at resolutions up to 32-bit, while native DSD operation covers 2.8224 MHz through 22.5792 MHz, corresponding to DSD64 through DSD512.

The SU-3 also provides optical and coaxial S/PDIF inputs for sources that do not use USB. Both interfaces accept PCM from 44.1 kHz through 192 kHz at bit depths from 16 to 24 bits. USB compatibility is specified for Windows 7, 8, 8.1, 10, and 11, macOS X 10.6 or later, and Linux.

Dual femtosecond oscillators for digital clocking

Two low-phase-noise femtosecond crystal oscillators provide clock references for the digital audio circuitry. Their function is to reduce phase noise and timing error in the clock signal used during conversion, maintaining stable timing across the DAC's supported sample rates.

32-band parametric EQ

The SU-3 includes a 32-band parametric EQ for detailed frequency-response adjustment. PEQ provides substantially finer control than conventional bass and treble adjustment by allowing individual frequency regions to be targeted, making it suitable for headphone response correction, loudspeaker tuning, room-related adjustments, or listener-defined tonal curves.

EQ settings are retained after the DAC is powered off, allowing stored adjustments to remain available after a restart without requiring the parameters to be entered again.

Balanced XLR and single-ended RCA outputs

Rear-panel analog connectivity includes balanced XLR and single-ended RCA outputs. The XLR connections deliver a specified 4 Vrms output, while the RCA outputs provide 2 Vrms. These standardized output levels allow the SU-3 to feed powered monitors, headphone amplifiers, preamplifiers, integrated amplifiers, and other equipment with line-level analog inputs.

Dedicated USB power filtering

A dedicated filtering stage is used on the USB power input to reduce incoming noise, ripple, and electromagnetic interference before it reaches the DAC circuitry. Power consumption remains below 5 W during operation and below 0.1 W in standby.

Compact CNC-machined aluminum chassis

The electronics are housed in a CNC-machined anodized aluminum alloy enclosure measuring 4.57 in wide, 1.57 in high, and 3.43 in deep (116 x 40 x 87 mm). The SU-3 weighs 0.683 lb (310 g), giving it a small footprint for desktop systems where space around a computer, headphone amplifier, or powered speaker system is limited.

Availability

The SMSL SU-3 is available now on Apos.