Stream Box S2 Ultra

  • Premium network bridge, bringing network connectivity to any USB DAC
  • Roon Ready certification makes set-up easy
  • USB detox process creates clean, detailed sound presentation

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How To Buy

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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.

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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.

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The Stream Box S2 Ultra is designed to bring high-end network connectivity to any USB-enabled DAC. Rather than having to consider expensive or inconvenient upgrades, the small size and attractive price of the Stream Box S2 Ultra means you don't need to change your system to enjoy wireless (or wired) streaming from any DAC with a USB input.

The USB output of the Stream Box S2 Ultra is meticulously engineered to offer the very best possible output signal. With its own dedicated internal power supply and premium components, the USB output "detoxes" the USB signal, removing noise and unwanted artefacts. The end-result is a sound presentation that is open, clean and detailed, but retaining the raw emotion of the music. 

Foremost as a Roon Ready network streamer, the Stream Box S2 Ultra is effortlessly simple to integrate. It's instantly recognised by your Roon server once connected to a USB DAC, so you can transmit via Roon's bespoke RAAT protocol and experience the full Roon experience from any existing, non-Roon-certified equipment.

Second, as a universal network bridge it offers a sophisticated solution for building a small music server based on the popular Volumio platform. Volumio allows for playback from Spotify, Tidal, Qobuz, Shoutcast (Internet Radio) and Shairport (Airplay), as well as UPnP network services or attached USB hard drives. Controlled over IP via the responsive in-browser app, or by using Pro-Ject's own Pro-Ject Play Android app, the Stream Box S2 Ultra is easy to navigate and enjoy - delivering its class-leading digital audio output signal no matter how you choose to use it.

The Stream Box S2 Ultra supports almost any file-type that your DAC does, opening up the option to handle even very high-resolution file types like 352.8kHz PCM and DSD256. If your DAC is MQA-enabled the Stream Box S2 Ultra can pass-through MQA signals without alteration, for exact unfolding by your DAC. The Net/PC button also allows for a PC or Server to be directly connected via USB - benefiting from the same USB detox process without the need to send signals over a wireless or wired network.

The Stream Box S2 Ultra is a cutting edge piece of kit. Capable of opening up new possibilities on even ultra-high-end DACs, or for simply building a small, bespoke audio streaming platform, its class-leading, high-end technology and compact footprint make it a must-consider add-on for any serious digital audiophile. 

Key Features:

  • High resolution network bridge with Roon Ready built-in
  • Network-enables and modern DAC with a USB input
  • Audio optimized USB A output with unique "detox" process
  • Multi-room enabled via Roon or Volumio
  • Two USB inputs for hard-drive connection or keyboard/mouse connections
  • Support for Tidal, Spotify, Qobuz, Shoutcast and Shairport via Volumio
  • DLNA enabled
  • Bypasses all audio formats to the DAC, supplying only a clean, bit-perfect USB signal
  • PC input allows for USB-connected PCs to benefit from the "detox" process
  • Bluetooth input (for control)
  • Uses dedicated power supplies
  • HDMI video output
  • Controllable via smart devices and PC/Laptop
  • Ethernet and WiFi connectivity
  • Available in Black or Silver finish

Technical Data

Audio Formats: PCM 32bit/352.8kHz
Internet Radio: Shoutcast
Streaming Services: TIDAL
Spotify (Volumio implementation)
Supported data protocols: Qobuz
Multi-room: Up to six devices
Inputs: 2 x USB A
Micro USB B (PC-Detox)
Network (Ethernet, WiFi)
Outputs: Audio optimized USB A
HDMI (Video)
Controllable via: App
Web Browser
Weight: 375g (without PSU)
Dimensions: 105 x 37 x 105mm (W x H x D)


How do you perform a system reset without access to the Stream Box Software?

  • Get a USB Thumb Drive
  • Format it as “FAT32”
  • Download this file
  • Copy it on the Thumb Drive (make sure the name of the file is exactly "factory_reset")
  • Turn off the Stream Box S2 Ultra • Plug the thumb drive to one of the USB ports
  • Turn on the Stream Box S2 Ultra
  • IMPORTANT: During this phase the unit might restart multiple times and this factory reset will take about 5 minutes.

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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