Pro-Ject DAC Box RS2 Digital-to-Analog Converter

Dual-mono ESS Sabre DAC with MQA decoding, tube or solid-state output, and fully balanced design

The Pro-Ject DAC Box RS2 is a purpose-built, high-end digital-to-analog converter distilled from the acclaimed Pre Box RS2 Digital. By removing the analog preamplifier section and committing to a fixed-output design, Pro-Ject focused the RS2 entirely on one job: converting digital audio with maximum precision, flexibility, and musical integrity. The result is a compact but uncompromising standalone DAC designed for modern high-resolution and streaming-based systems.

At its core, the DAC Box RS2 employs a true dual-mono architecture using a pair of ESS Sabre ESS9038Q2M DAC chips, with fully independent signal paths for left and right channels. This approach, rare at this price point, improves channel separation, lowers noise, and enhances spatial definition. High-resolution playback is fully supported, with PCM up to 32-bit / 768 kHz and DSD up to DSD512 via USB, ensuring compatibility with virtually any current digital format.

Tube or Solid-State Output

The analog output stage offers a unique level of user choice, allowing switching between a solid-state output and a high-quality tube output. This gives listeners the ability to tailor the presentation to their system and preferences, from maximum transparency to a more harmonically rich character. Eight selectable digital filters are provided, including the proprietary Optimal Transient filter developed by the creators of MQA, further extending the ability to fine-tune the sound.

Full hardware and software support for MQA (Master Quality Authenticated) is built in, making the DAC Box RS2 an ideal partner for high-resolution streaming services such as TIDAL. USB signal handling is managed by a powerful multi-core XMOS processor, while precision re-clocking is handled by an Altera MAX II CPLD, minimizing jitter and preserving timing accuracy for both standard PCM and MQA playback.

Versatile System Integration

System integration is equally thoughtful. The DAC Box RS2 can be paired with Pro-Ject’s Stream Box S2 Ultra or the CD Box RS2 T transport, the latter connecting via a differential I²S interface over HDMI and sharing a master clock for optimal synchronization. A large, clear front-panel display provides comprehensive playback information, and menu navigation is fast and intuitive.

A premium full-aluminum remote control is included, and the DAC Box RS2 is housed in a precision-machined aluminum chassis available in silver or black. Compact, versatile, and technically sophisticated, the DAC Box RS2 is designed for listeners who want state-of-the-art digital performance without unnecessary complexity.

Specifications

DAC: 2 x ESS9038Q2M (dual mono, 32-bit / 768 kHz, DSD512)

Digital Inputs: 1 x USB 2.0 Audio (up to 32-bit / 768 kHz, DoP and native DSD up to DSD512)
1 x HDMI I²S (for CD Box RS2 T)
2 x S/PDIF optical (up to 24-bit / 192 kHz)
1 x S/PDIF coaxial (up to 24-bit / 192 kHz)
1 x AES/EBU balanced (up to 24-bit / 192 kHz)

MQA Support: Full MQA unfolding by hardware

Output Impedance: 180 Ω solid state, 220 Ω tube

Analog Outputs: Pre-out (XLR, RCA)

THD+N (20 Hz–20 kHz): <0.0008% solid state, 0.001% tube @ 2 V RMS, 1 kHz

Master Clock Output: 16.9344 MHz (for CD Box RS2 T)

Output Buffer: Discrete and balanced, tube and solid-state

Tubes: 4 x 6922EH

Power Supply: 20 V / 3 A DC, 110–240 V / 50–60 Hz

Power Consumption: Max 1.2 A DC, <0.5 W standby

Dimensions (WHD): 8.11" x 2.83" x 8.74" (206 x 72 x 222 mm) 

Weight: 3.35 lb. (1.52 kg) without power supply