2022 Stereophile Recommended Component

Stream Box S2 Ultra offers modern connectivity with its network inputs and USB A output. This USB output is optimized specifically for audio signals. The streaming device uses a dedicated internal power supply and audiophile-grade components to achieve the sonics that has made this unit famous. You won’t encounter file-support issues as Stream Box S2 Ultra acts as a bit-perfect network bridge, sending files directly to your digital-to-analog converter via USB.

Since most DACs have one USB port, we have designed Stream Box S2 Ultra also as a USB detox device for a cleaner audio signal. Simply connect your PC to the micro USB input of the unit and connect your DAC to the audio output; this way the digital signal is optimized while you listen. Control is simple thanks to our iOS and Android-compatible “Pro-Ject Play” app. Alternately, the StreamBox S2 Ultra can be controlled via web browser or the very popular Roon software.

Additional information
Weight 0.375 kg
Dimensions 10.5 × 10.5 × 3.7 cm



  • High resolution network bridge
  • Audio optimized USB A output
  • Multi-room enabled
  • Dual USB A input for external storage
  • MQA capable w/ Pre Box S2 Digital, DAC Box RS2 & Pre Box RS2 Digital
  • Tidal, QoBuz, Spotify, high-res audio streaming
  • Network-enables any modern DAC with USB input
  • Internet Radio (TuneIn)
  • DLNA enabled
  • Bypasses all audio formats to the DAC
  • Cleans up the audio signal from a PC
  • Fully Roon Ready and certified
  • Shairport
  • Bluetooth
  • Uses dedicated power supplies
  • HDMI video output
  • Controllable via smart devices and PC/Laptop
  • New control app!
  • Ethernet and WiFi connectivity
  • Handmade in Europe


  • Internal Memory: 16 GB
  • Audio formats: PCM 32bit/352.8kHz, DSD256
  • Internet radio: Shoutcast
  • Supported data protocols: RAAT, Shairport, DLNA
  • Multi-room: up to six devices
  • Inputs: 2 x USB A (maximum combined current draw 1A)
  • Micro USB B (PCDetox),
  • Network (Ethernet, WiFi)
  • Bluetooth
  • Supported WiFi standards: 802.11 b/g/n/d/e/h/i
  • Bluetooth: Bluetooth Classic + EDR v2.1, v3.0, v4.0 and Low Energy
  • Outputs: audio optimized USB A, HDMI (video)
  • Outboard power supply: 18V/1A DC (included)
  • Wi-Fi antenna included