SMSL SU-1 DSP: Desktop DAC With 32-Band PEQ

The SMSL SU-1 was released internationally on October 30. Although SMSL launched the SU-3 in September of this year, the company decided to introduce a new version of the first-generation model in its “SU” desktop DAC series. The SU-1 DSP differs from the original in only one respect: its 32-band parametric equalizer (PEQ). Full details of this new SMSL release are provided below.

SU-1 DSP Features a 32-Band PEQ

With hardware identical to that of the original SMSL SU-1 (OG), the SU-1 DSP differs only in its support for a 32-band parametric equalizer (PEQ). This new version of the SU-1 uses the same AKM AK4493S DAC chip and XMOS XU-316 USB controller. The connections also remain unchanged: USB-C, optical TOSLINK, coaxial, and RCA.

How Does the SU-1 DSP’s Parametric Equalizer Work?

Creating equalization profiles and saving them to the SU-1’s memory requires SMSL’s dedicated parametric equalizer web app. The app requires no driver or software installation and operates using WebHID technology. To use it, simply connect the DAC to a computer via USB, open a browser, and follow this link.

What Are the Differences Between the SU-1 DSP and the SU-3?

The main difference between the SU-1 DSP and the SU-3 is the balanced XLR line output. Both models support a 32-band PEQ and an AKM DAC.

While the SU-1 DSP has only a single-ended (SE) RCA line output, the SU-3 has both RCA and XLR line outputs. The RCA line output level is 2 Vrms on both the SU-1 DSP and the SU-3, whereas the SU-3’s XLR line output level is 4 Vrms.

If your amplifier has balanced XLR inputs, paying the price difference of nearly US$100 between the SU-1 DSP and the SU-3 may be worthwhile.

SMSL SU-1 DSP Connections and Physical Buttons

The diagram below shows the SMSL SU-1 DSP’s connections and physical buttons.

SMSL SU-1 DSP: Specifications

• Analog outputs: Single-ended (SE) RCA
• Chassis material: Anodized aluminum alloy
• Color: Black
• DAC chip: AKM AK4493S
• Digital inputs: USB, optical, and coaxial
• Dimensions: 96 × 27 × 78 mm
• Dynamic range: 121 dB
• Power consumption: 5 W
• Signal-to-noise ratio (SNR): 121 dB
• Single-ended (SE) RCA line output level: 2 Vrms
• Standby power consumption: 0.1 W
• Support for a 32-band parametric equalizer (PEQ)
• Supported formats via the optical and coaxial inputs: PCM up to 24-bit/192 kHz
• Supported formats via the USB input: PCM up to 32-bit/768 kHz and DSD512
• Supported operating systems: Windows 7 / 8 / 8.1 / 10 / 11; Mac OS X 10.6 or later; Linux
• THD+N: 0.00013% (−117 dB)
• USB controller chip: XMOS XU-316
• USB transmission: Asynchronous
• Weight: 198 g

Release, Pricing, and Availability

The SMSL SU-1 DSP is now available internationally in black for US$99 through the Shenzhenaudio store on AliExpress.