Pro-Ject Pre Box RS2 Digital Preamp w/ DAC & Headphone Amp - Clearance

The Pro-Ject Pre Box RS2 Digital is a high end preamplifier, DAC, and headphone amplifier built for listeners who want a single compact hub for serious two channel and headphone systems. It combines dual mono ESS9038Q2M DAC chips, fully balanced analog topology, a selectable tube or solid state output stage, and extensive digital input support in one chassis. Use it as a DAC and preamp for your power amplifier and speakers, as a high performance headphone amp, or as the digital control center of a full RS2 stack.

Based on the core design of the award winning Pre Box S2 Digital, the RS2 version pushes resolution, flexibility, and build quality much further. It supports PCM up to 32 bit 768 kHz, DSD up to DSD512, and full hardware MQA unfolding. With both XLR and RCA outputs, plus a discrete DC coupled headphone stage, it is as comfortable feeding a reference power amp as it is driving demanding headphones.

Dual mono DAC and digital architecture

Pre Box RS2 Digital uses two ESS9038Q2M converters in a dual mono layout, with fully separate signal paths for left and right channels. The USB input is handled by a powerful multi core XMOS controller, while an Altera CPLD manages reclocking. Together they reduce jitter and provide a stable digital foundation for conventional PCM, DSD, and MQA playback.

Sample rates up to 32 bit 768 kHz and DSD512 are supported through USB. Eight digital filter options are available, including the proprietary optimal transients filter from the MQA team, so you can fine tune the presentation to taste. Hardware MQA unfolding works on all digital inputs, including I²S, coaxial, optical, AES EBU, and USB.

Tube or solid state output

One of the defining features of Pre Box RS2 Digital is its selectable output stage. At the press of a button you can choose a fully discrete solid state path or a 6922 based tube output. This lets you match the sound to your system and mood. The solid state stage offers ultra low distortion and maximum linearity, while the tube mode adds a slightly more relaxed and harmonically rich character.

Both stages sit behind a fully balanced analog signal path with separate XLR and RCA outputs. Use it as a fixed level DAC, a variable level preamp, or directly into a power amp or active speakers.

Headphone amplifier

The built in headphone amplifier is a discrete, no compromise design. It is DC coupled with a fast servo to remove any DC offset, and it avoids coupling capacitors in the signal path. With power output up to 245 mW into 33 ohms and 90 mW into 300 ohms, it can handle a wide range of headphones from efficient dynamics to more demanding planar designs.

System integration and RS2 ecosystem

Pre Box RS2 Digital is designed to integrate cleanly into both standalone and stack based systems. It offers nine digital inputs, including I²S over HDMI for direct connection to Pro Ject’s CD Box RS2 T transport. In this configuration the Pre Box RS2 Digital can provide the master clock at 16.9344 MHz for improved timing.

Paired with a Stream Box S2 Ultra, it becomes a Roon Ready, network enabled front end for Tidal, Qobuz, local libraries, and more, with full MQA decoding. Trigger in and trigger out jacks make it easy to power the system on and off in sync with other RS2 components.

Build, interface, and control

The Pre Box RS2 Digital is housed in a solid aluminum enclosure and is available in black or silver. The front panel features a large 3.5 inch TFT display that clearly shows sample rate, input, filter, and status information. The interface is fast and direct, and a full aluminum remote control is included for easy operation from the listening position.

Technical Specifications

What is in the Box

• Pro-Ject Pre Box RS2 Digital
• 20 V 3 A DC power supply
• Aluminum remote control
• Owner’s manual

FAQ