Pro-Ject Pre Box RS2 Digital

Pre-amplifier and headphone amp with a dual-mono Sabre DAC with tube or solid-state buffer, and full MQA support

The Pre Box RS2 Digital is the bigger brother of Pro-Ject’s  award-winning and groundbreaking Pre Box S2 Digital. It uses a dual-mono Sabre chip configuration (ESS9038Q2M) offering separate DACs and signal paths for the left and right channels. It supports up to 32-bit / 768 kHz files in PCM and DSD formats (up to DSD512) via USB.

The Pre Box has eight digital filters. One of them is the proprietary optimal transient digital filter from the MQA creators. With these filters, the listener can customize the sound to suit their own preferences. Pre Box RS2 Digital comes with full hardware and software support for MQA (Master Quality Authenticated).

The analog output offers a choice of tube or solid-state buffer.

In the Pre Box, the USB input signal is processed by a powerful multi-core XMOS microcontroller with advanced Multi-Core RISC architecture. The CPLD MAX II (Complex Programmable Logic Device) Altera is used for re-clocking, which together with the XMOS microcontroller brings high-quality processing of both classical and MQA technology. For the ideal use of this technology, it is best to connect the Pre Box to the Stream Box S2 Ultra in conjunction with the TIDAL service.

You can also enjoy MQA quality by linking it with Pro-Ject’s new revolutionary CD transport, the CD Box RS2 T. The CD Box RS2 T can be connected to the Pre Box by reliable I²S differential bus via the HDMI connector where the Pre Box RS2 Digital also provides the master clock (16.9344 MHz).

The headphone amplifier has no coupling capacitors, not even on the output. All of the the amplifier is DC coupled, and a fast DC servo assures no DC voltage on the output. 

A premium full aluminum remote control is included, and a big display screen on the front shows all relevant information in an easy to read way. 

Features

• Dual Mono ESS9038Q2M DAC
• High-quality optionally selectable upsampling of PCM and/or MQA content with proprietary filtering
• Full MQA unfolding by hardware
• Advanced re-clocking powered by new XMOS chip with Multi-Core RISC architecture
• 9 digital inputs: i²S HDMI, AES/EBU, Toslink, S/PDIF coax, Bluetooth v4.0
• Pre-out XLR/RCA/headphone, RCA input
• Fully balanced double mono design
• Output stage switchable between 6922 tube and solid state
• Ultra-linear and ultra-low-noise
• New high-quality display with responsive and fast UI design
• High-quality full aluminum remote control included

Specifications

DAC chip: 2 x ESS9038Q2M (dual mono – 32bit/768kHz/DSD512)

Inputs
Digital: 1 x USB 2.0 Audio 32/768 + DoP and Native-DSD up to DSD512, 1 x HDMI I2S for CD Box RS2 T, 2 x S/PDIF optical 24/192, 1 x S/PDIF coaxial 24/192, 1 x AES/EBU balanced 24/192
Wireless: Fully embedded Bluetooth® v4.0
Analog: 1 x XLR stereo, 1 x RCA stereo 

Input impedance: 15 kOhm

Output impedance (solid-state, tube): 180 ohm, 220 ohm

Analog outputs: 2 x pre-out (XLR & RCA), headphone (6.35 mm)

Headphone output power (300, 32, 8 ohm): 90 mW, 245 mW, 150 mW

Masterclock output: 16.9344 MHz for CD Box RS2 T

Tube complement: 4 x 6922EH

Dimensions (WHD): 8″ x 2.8″ x 8.7″

Weight (without power supply): 3.77 lb