USB Box S+

  • Premium 32-bit / 384kHz PCM-5102A DAC chip from Burr Brown
  • Upsampling to 352.8kHz or 384kHz
  • Dedicated USB 2.0 driver for Windows Operating Systems (Apple and Linux are driver-less)

This is a Special Order item.

Due to circumstances relating to this product, it is only available in the UK to special order, which means it is not stocked as standard in our warehouse. A special order item will be placed on order with the relevant manufacturer during our next scheduled Purchase Order. As we forecast orders up to two months ahead of time with some suppliers, this does not mean the item will automatically be included on the next shipment we receive. It also does not mean that the item will immediately be placed on order with the supplier, as we group special orders together for logistical purposes. Therefore, we estimate lead times on most special order items of 8 – 12 weeks.

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How To Buy

As UK distributors for the brands we represent, our main focus is to give you all the information you need to help assist with your purchase. Once you have the information you need, we want to make the purchase process as simple as possible. So we give you up-to three options on how to buy our products.

Find Your Local Retailer

Our preferred option is for you to visit a nearby store and buy what you need locally. Our authorised stockists are some of the finest specialist hi-fi retailers in the country, and they're equipped to give you the best after-sales and set-up advice possible - all in person. To find your local retailer, either click the 'Buy In-Store' button on your product page for exactly the right recommendation, or head to our comprehensive Where To Buy tool.

Buy Now, Collect Locally

If you want the added convenience of only having to pop-in to store when you know the product you want has arrived, you can use our Click & Collect-style checkout process. With Buy Now, Collect Locally, your purchase takes place online and the product is then delivered direct to your local supporting retailer; ready for you to collect when you're ready. Click here to find out more about Buy Now, Collect Locally.

Buy Now

For smaller items, you can also have the ultimate convenience of purchasing directly through our website. The checkout process is entirely secure, so you can trust your information will be safe - and your desired product will arrive with you as quickly as possible.

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The USB Box S+ from Box Design by Pro-Ject Audio uses the most advanced features and technologies in USB asynchronous data transfer thanks to a high-end XMOS chipset. This simple-to-use Digital/Analogue Converter (DAC) connects to your computer via USB and to a hi-fi system through traditional RCA leads to open the world of computer audio to your hi-fi. 

Inside the USB Box S+ is a PCM5102A DAC chip from Burr-Brown, which is able to deliver very good signal to noise ratio, very good dynamic range, low distortion and a very low output impedance. This premium chip is also capable of handling up to 32-bit/384kHz digital audio files, opening up the world of studio-grade DXD (Digital eXtreme Definition) audio.* 

Set-up is as simple as plug-and-play with Apple and Linux systems, while Windows systems just need Pro-Ject's audio drivers installed for quality playback of 24-bit/192kHz audio files.* The USB Box S+ also highlights the sample rate of the current audio file, by lighting the corresponding light on the clearly laid out front panel. The filter button switches between two filter designs (Minimum Distortion / Optimum Phase)** that can further tailor the sound to suit your preference.

USB Box S+ up-samples data on 352.8kHz or 384kHz (44.1kHz, 88.2kHz & 176.4kHz are upsampled on 352.8kHz. 48, 96 & 192kHz are up-sampled on 384kHz), meaning every digital detail is captured for conversion - resulting in a truly musical playback through your Hi-Fi.

Compared to conventional 24bits/96kHz DAC technology, the USB Box S+ offers lowest possible jitter and up to 20dB lower noise levels. There are also no superfluous components, which keeps the analogue signal path clear of potential degradation. The use of an external power supply reduces potential electromagnetic on the board, as does the heavy metal enclosure that protects the internal boards from external influences.This little Box takes USB streaming to another level!

* The USB Box S+ is supplied with a disc that contains Pro-Ject's latest ASIO drivers for hi-res audio playback on Windows machines. Apple or Linux machines should not need any additional drivers installed. Only certain programs are capable of handling 32-bit/384kHz audio (Foobar 2000, JRiver, Mediacentre etc.).
** The two filters are “Brick Wall” FIR (Finite Impulse Response) and “Apodizing” IIR (Infinite Impulse Response), respectively.

Available with Black or Silver faceplate

Key Features:

  • Premium 32-bit / 384kHz PCM-5102A DAC chip from Burr Brown
  • XMOS technology for lowest possible jitter
  • Upsampling to 352.8kHz or 384kHz
  • 32-bit / 384kHz asynchronous USB streaming
  • Dedicated USB 2.0 driver for Windows Operating Systems (Apple and Linux are driver-less)
  • 2 Selectable filters
  • Ultra-linear circuitry
  • Extremely low impedance on output stage
  • Silver or Black face-plate

Technical Data

Inputs: 1x USB Type-B
Outputs: 1x Unbalanced RCA (Pair)
D/A Converter: Burr-Brown PCM-5102A Multibit Delta Sigma
Bit-Depth Handled: Up to 32-bit
Sample Rates Handled: 32kHz
Output Voltage: 2.1V rms
Frequency Response: 20Hz - 50kHz (0db;-1dB)
Selectable Filters: 2 (Minimum Distortion / Optimum Phase)
Power Supply: 9V/300mA
Dimensions: 103 x 36 x 109mm (Incl. Sockets)
Weight: 576g (Without PSU)


Does the device support Windows 10?

The device is fully compatible with Windows 10. It may be necessary to reinstall latest drivers after updating from Windows 7/8/8.1 to Windows 10.

Does a driver exist for Mac OSX- or Linux-Systems?

You do not need a driver. The driver is already integrated in the operating system.

USB Box S+ will not be recognized by Mac OSX and is not available under Audio. What can I do?

Turn off your Computer and press at start alt+cmd+p+r until another starting sound appears. With this command the USB bus will be reset and the USB Box will be recognized new.

For more help and advice visit our Tech Support section

Note: We’re constantly updating our website to ensure all our listings are as accurate as possible. However, the images and text on this page can be subject to change without notice, and errors and omissions are excepted.

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