Pro-Ject Pre Box S2 Digital

Micro-sized digital stereo preamp with built-in headphone amp - amazing piece at an amazing price!


In very nice condition! Includes original remote, box and packing. Manual can be found on the internet.  White bakground pix are stock.

Best DAC/Headphone Amplifier 2017-2018 Award - EISA, the European Imaging and Sound Association

"Great, Affordable Hi-Fi" with Hardware MQA Decoding

The new Pre Box S2 Digital compact preamplifier/DAC with MQA and DSD512 support marks a new era for Pro-Ject's renowned S-series components. And it's Roon-ready, too. For the very first time ever, Pro-Ject is using a dual mono configuration with flagship D/A converters made by ESS Sabre. The cutting-edge ESS9038 dual DAC ensures the highest quality audio performance in a small and affordable package. This DAC is capable of high resolution audio up to an impressive 32-bit, 768 kHz PCM and DSD512!

The Pre Box S2 Digital won a Best DAC/Headphone Amplifier 2017-2018 Award from EISA, the European Imaging and Sound Association, a unique association of nearly 50 trade publications from 23 European countries. "With an open and expressive nature, and supreme versatility, the Pre Box S2 Digital sounds bigger and bolder than it looks - making it great affordable hi-fi." Proprietary Clock Circuitry Design: Pre Box S2 Digital is also the very first Pro-Ject devices to support hardware MQA decoding. And it's also a Roon-ready product. Pre Box S2 Digital premieres the company's proprietary Optimum transient digital filter and its proprietary clock circuitry design.

Pro-Ject is using a 16-core XMOS chip for asynchronous USB data transfer and full MQA hardware unfolding. The DAC directly controls the XMOS chip. A four layered, gold plated PCB with extra shielding is used to achieve optimal audio performance. Digital audio is all about the art of time, and with Pro-Ject's new proprietary clock design, the Pre Box S2 Digital manages jitter rates of unrivalled 100 Femtoseconds, which easily outperforms many renowned and respected audiophile clock generators.

Extremely Low-Noise USB Operation: A huge problem for USB DACs is the transmission of noise through the USB output. Pro-Ject vastly reduces the noise through both actively and passively filtering the output. After applying passive RF interference filtering, noise on 1 kHz drops to -125 dB, and at 10 kHz noise comes even close to -160 dB. Applying an active filter after the passive filtering has even more impressive results that are limited by the capabilities of the measuring equipment. The noise floor is at -160 dB or even lower.

Blows Away Much Larger Components: With organic polymer capacitors and thin film mini-MELF resistors, Pro-Ject was able to create a tiny device that will blow away even much bigger components for a much higher price. With a total of seven digital filters available onboard (including the proprietary Optimum transient digital filter), the sound can be shaped precisely to the listeners liking.

Pre Box S2 Digital is fully remote operation capable, and it can also control the playback software of a computer. For convenient fast access to your music, you can also access the Play, Pause, Forward, and Rewind functions directly from your Pre Box S2 Digital front panel.

Pre Box S2 Digital provides up to 24-bit, 192 kHz decoding via its optical and coax inputs and up to 32-bit, 768 kHz via USB.

Technical Info on the Internals

Pro-Ject is using dual DAC 2 x ESS9038Q2M, the newest generation of SABRE Digital to Analog Converter. The ES9038 SABRE DAC is a high-performance 32-bit digital to analog converter and uses ESS's patented 32-bit Hyperstream II modulator architecture and Time Domain Jitter Eliminator. It is the first SABRE DAC to use new Dual-DAC architecture to further enhance performance. It also delivers an unprecedented dynamic range of up to 129dB and total harmonic distortion plus noise of -120dB (THD+N) - a performance level that will satisfy the most demanding audio enthusiasts.

The ESS9602 is used for the headphone amplifier and output buffer. It supports a dynamic range of up to 122dB and THD+N of -117dB with 600ohm loads. Additionally, Pro-Ject implemented a unique feature that improves THD+N with 32ohm loads to -112dB in Best Performance mode.

The ESS9311 is the industry's first low-noise, low-dropout regulator designed specifically for high-performance audio systems. It is optimized for high resolution audio thanks to its revolutionary dual regulator architecture. This innovative architecture contains series-voltage and shunt-voltage elements, eliminating the need for output decoupling capacitors - an industry first in audio system design. The ESS9311 provides the extremely low-noise outputs that are necessary for driving the reference inputs of audio converters and offers significant value-add for audio system designers.

Preamp with built-in DAC

Dual mono construction

Compatible with MQA audio files


Hi-Res certified

High end ESS Sabre ESS9038 dual DAC

Proprietary clock circuity design

Organic polymer capacitors and thin film miniMELF resistors

MQA hardware decoding

DSD64, DSD128, DSD256 & DSD512 (DSD over PCM)

Up to 24bit/192kHz for optical & coax inputs

7 selectable digital filter characteristics

1 proprietary Optimum transient digital filter

Headphone output on the front (6.3mm)

Synchronization of all internal oscillators

Jitter as low as 100 Femtoseconds!

User-friendly design with display

Gold-plated four layer PCB

Full alu/metal sandwich casing in silver or black

3 digital inputs: 1x coax (S/PDIF), 1x optical (TOSlink), USB-B

Analog out 6.3mm Headphone Out (front), 1x Variable Out (RCA)

D/A-converter: 2x ESS9038Q2M 32-bit PCM 768kHz / DSD512

Headphone amplifier chip: ESS9602

Sampling rates: 32, 44.1, 48, 88.2, 96, 176.2, 192, 352.8, 384, 768 kHz

MQA support: Full MQA decoding by hardware

Frequency response: 20Hz - 20kHz

Output voltage: 2.05 V eff

Headphone output power: 68mW (32Ohms)

THD: 0.0003%

Dynamic Range: 124dBA

Power consumption: 5V, micro USB

Dimensions W x H x D: 4" x 1.4" x 4"

Weight: 21 oz. without power supply

Our Return Policy