RME Digiface USB – 66-channel USB 2.0 audio interface with 4× optical ADAT/SPDIF I/O (up to 32×32 @ 44.1/48 kHz; SMUX up to 96 kHz, SMUX4 up to 192 kHz), a DC-coupled 6.3 mm headphone/line output (channels 33/34), and TotalMix FX mixer (without DSP effects), powered via USB bus.
Digiface USB is an ultra-compact digital hub: each of the four optical ports functions as ADAT (8 channels) or SPDIF (stereo), with automatic format detection on inputs and independent format switching on outputs. TotalMix FX allows you to create up to 17 independent stereo submixes and route any signal freely, while the 6.3 mm headphone output (channels 33/34) enables direct monitoring without additional converters. The interface supports SMUX/SMUX4, works without a power adapter (bus-powered), and is compatible with the ARC USB remote and DIGICheck analysis software.
KEY FEATURES
- 4× ADAT/SPDIF I/O via TOSLINK (up to 32×32 @ 44.1/48 kHz; SMUX/SMUX4 up to 192 kHz)
- 6.3 mm TRS analog output (channels 33/34), DC-coupled – headphone or line output
- TotalMix FX for flexible routing (no DSP FX); up to 17 stereo submixes
- Independent format selection on each optical output; auto-format detection on inputs
- Bus-powered via USB 2.0; compact and lightweight enclosure
- Compatible with ARC USB and DIGICheck software tools
TECHNICAL SPECIFICATIONS
- I/O: 4× optical input TOSLINK (ADAT/SPDIF), 4× optical output TOSLINK (ADAT/SPDIF); 1× 6.3 mm TRS headphone/line output (channels 33/34)
- Total channels: 32 inputs / 34 outputs (66 channels over USB)
- Modes and sample rates: Standard 32×32 24-bit @ up to 48 kHz; Double Speed (SMUX) 16×16 @ 88.2/96 kHz; Quad Speed (SMUX4) 8×8 @ 176.4/192 kHz
- Phones Out (33/34): DR 110 dB RMS (113 dBA), THD+N −95 dB (0.0017%), impedance 2 Ω, level 0 dBFS/1 kΩ: +9.5 dBu, max power 50 mW; frequency response (−0.5 dB): 0 Hz–20.8 kHz @ 44.1 kHz; 0–45 kHz @ 96 kHz; (−1 dB): 0–89 kHz @ 192 kHz
- Clock and formats: internal/ADAT In/SPDIF In; SPDIF (IEC 60958) supported on all optical ports; PLL Bitclock, lock range 31.5–50 kHz
- Supported sample rates: 28–200 kHz
- USB: type B, USB 2.0 (RME drivers for Windows/macOS); bus-powered (typical power ~1.2 W / 5 V 230 mA)
- Dimensions/weight: 128 × 22 × 55 mm; 220 g






