The Stream Box S2 ULTRA works as a network bridge: it brings streaming, internet radio and high-resolution files to any DAC with a USB input through a USB A output optimised for audio, and also cleans up the USB signal from a computer.
Stream Box S2 ULTRA: the design
It has no converter inside and no analogue outputs: its job is to give network functions to a USB DAC that lacks them, whether new or ageing. Files pass through to the converter untouched, so decoding is left to the DAC; handling goes as high as PCM 32-bit / 352.8 kHz and DSD256. The USB A output has its own internal power supply and parts selected for audio. Pro-Ject suggests pairing it with the Pre Box S2 Digital.
It joins the network over Ethernet or Wi-Fi. TIDAL, Spotify, Qobuz and HIGHRESAUDIO streaming are built in, along with internet radio through TuneIn. It is certified Roon Ready and speaks the RAAT, DLNA and Shairport protocols, the last aimed at people with Apple devices; Bluetooth is on board too. In a multi-room set-up it can run alongside others for a total of six units.
Two USB A inputs, one at the front and one at the rear, take external drives holding your own music; with an external USB CD drive, discs can be ripped as well. The micro USB B input is for the function Pro-Ject calls USB detox: the computer goes in there, the DAC stays on the audio output, and the signal reaches the converter freed of the PC's noise.
Control is through the iOS and Android app, which is based on an open-source project, through an ordinary web browser or through Roon. The HDMI output at the rear is video only: plug in a monitor and the graphical interface appears, ready for choosing music. The unit is offered in more than one finish.
Specifications
- Type: network bridge with USB output for an external DAC
- Audio formats: PCM to 32-bit / 352.8 kHz, DSD256
- Streaming services: TIDAL, Spotify, Qobuz
- Internet radio: TuneIn
- Protocols: RAAT (Roon Ready), Shairport, DLNA
- Multi-room: six units at most
- Inputs: 2 USB A for external storage, micro USB B for a computer
- Network: Ethernet and Wi-Fi 802.11 (standards b, d, e, g, h, i, n)
- Bluetooth: Classic with EDR in versions 4.0, 3.0 and 2.1, plus Low Energy
- Outputs: USB A tuned for audio, HDMI (video only)
- Control: Roon, web browser, app
- Weight: 375 g, power supply excluded
- Size (width x height x depth): 105 x 37 x 105 mm
- Finishes: black, silver
