Pro-Ject Uni Box S3 Streaming Integrated Amplifier

Uni Box S3 Streaming Integrated Amplifier, by Pro-Ject Audio Systems.

Released in June 2025, the Uni Box S3 dares to break away from the norm, redefining what a modern streaming amplifier can be. While many amplifiers are dominated by deeply integrated streaming tech – compromising their core design – the Uni Box S3 takes a different path.

Uni Box S3 masterfully bridges the worlds of analogue and streaming. Your analogue sources - like turntables - are not digitized, preserving their rich and lifelike sonic character.

With a fully-analogue pre / power amp design, every nuance of your music is delivered with breathtaking punch and dynamic precision.

The Pro-Ject Audio Systems mastery of analogue hardware design allows them to craft an astonishingly powerful amplifier within the sleek, compact aluminium case of the Uni Box S3. All this power remains usable entirely without a mobile app or the need to constantly update software.

The Uni Box S3 allows you to stream any of your connected devices – turntable, CD player or even TV – to other compatible streamers.

Partnering with WiiM, the Uni Box S3 streaming technology is powered by the industry leading WiiM OS™. The Cirrus Logic CS4344 DAC offers a high quality resolution of up to 24bit and 192kHz.

With the Pro-Ject Home app you control the streaming options on input 8 - the streaming input. Setting up the WiFi connection is a breeze. Just open the app and it automatically detects your new Uni Box S3 and walks you through the setup process. Comfortably reset the WiFi connection via long press of the Stream button on the front panel.

Features

• NEW Streaming by market leading technology WiiM OS.
• NEW App Pro-Ject Home.
• NEW Powerful Multi-Room capabilities.
• NEW Pro-Ject True Wireless Sending and Receiving: Stream any input to your network.
• NEW Countless streaming services.
• NEW Tidal Connect, Spotify Connect, Qobuz and more.
• NEW TV ARC input.
• Wireless vinyl streaming from T2 W.
• 2 x 40 watts @ 4 ohms.
• Dual mono design principle.
• 8 inputs (3x analog, 3x digital, 1x eARC, 1x WiFi/Bluetooth).
• Cirrus Logic CS4344 24bit/192kHz Multi-bit Delta Sigma.
• S/PDIF inputs support up to 24-bit and 192 kHz.
• Phono MM input.
• Analogue volume control with motor driven potentiometer.
• 6.3 mm jack headphone output.
• Variable output for subwoofer or second zone amp.
• Remote control included.
• Rigid aluminium casing protects against interference.
• Available in silver or black.

Specifications

• Power Output: 2 x 23 W / 40 W at 8 / 4ohms (1% THD)
• Frequency Response (20 Hz - 20 kHz): Less than 0.4 - 0.9 dB @ 4 Ohms
• Channel Separation: - 67 dB at 10 kHz
• Signal-to-Noise Ratio: 94 dB (9 dB‚ A-weighted) @ 4 Ohms
• THD: Less than 0.05 % @ 10 W / 4 Ohms
• Headphone Amplifier: 70 mW @ 32 Ohms (1 % THD)
• Analogue Inputs: 2 x pair RCA, 1 x phono MM (RCA)
• Digital Inputs: 1 x RCA coax, 2 x Toslink, 1 x eARC, WiFi / BT
• Power Amplifier: Texas Instruments TPA3221DDV
• DAC: Cirrus Logic CS4344 24-bit / 192 kHz
• Variable output: 1 x pair RCA
• Speaker Connectors: 4 mm banana plugs, spade connectors or bare wire
• Wireless Connectivity: Wi-Fi 5, 802.11 b/g/n/ac 2.4 G and 5G dual bands, Bluetooth 5.1, SBC and AAC
• Power Supply: 20 V / 3 A DC, 100 - 240 V, 50 / 60 Hz
• Standby Power Consumption: Less than 0.5 W
• Dimensions (W x H x D): 206 x 55 x 153 (176 mm with sockets)
• Weight: 1100 g without power supply

Included

• 1 x Uni Box S3
• 1 x Remote Control

More Information

• Uni Box S3, by Pro-Ject Audio Systems