A stereo integrated amplifier with streaming based on WiiM OS: 2 x 40 W into 4 ohms, an MM phono input, line, digital and HDMI ARC inputs, dual-band Wi-Fi and Bluetooth, all in a compact aluminium chassis.
Uni Box S3: analogue and streaming together
Pro-Ject's Uni Box S3 goes a different way from many streaming amplifiers, in which the network side shapes the whole design. Here analogue sources, the turntable included, are not converted to digital and keep their own character: preamplifier and power stage are described by the maker as entirely analogue. The unit can be used in full with no app on the phone and no need to keep updating software.
Streaming comes from a partnership with WiiM and runs on WiiM OS; conversion is handled by a Cirrus Logic CS4344 at 24 bit and 192 kHz. The Pro-Ject Home app manages the network functions on input 8, the one set aside for streaming: it finds the amplifier by itself and leads the user through Wi-Fi configuration, which is cleared by holding down the Stream key on the fascia. Any connected source, from turntable to CD player to television, can be sent on to other compatible streamers.
Inputs comprise one MM phono, two line-level RCA pairs, one coaxial, two optical and ARC for the television, plus Wi-Fi 5 on 2.4 and 5 GHz and Bluetooth 5.0 with SBC and AAC codecs. The output stage uses the Texas Instruments TPA3221DDV and gives 23 W per channel into 8 ohms and 40 W into 4 ohms. A variable RCA output, a headphone output of 70 mW into 32 ohms and terminals for 4 mm banana plugs, spade lugs or bare wire complete the picture.
Specifications
- Type: stereo integrated amplifier with WiiM OS streaming
- Power: 2 x 23 W into 8 ohms, 2 x 40 W into 4 ohms (1% THD)
- Channel separation: 67 dB measured at 10 kHz
- S/N ratio: 94 dB into 4 ohms
- Distortion: below 0.05% with 10 W into 4 ohms
- Headphone output: 70 mW into 32 ohms (1% THD)
- Analogue inputs: two line-level RCA pairs, one MM phono on RCA
- Digital inputs: one RCA coaxial, two Toslink optical, HDMI ARC, Wi-Fi and Bluetooth
- Output stage: Texas Instruments TPA3221DDV
- DAC chip: Cirrus Logic CS4344, 24 bit / 192 kHz
- Variable output: one RCA pair
- Speaker terminals: for 4 mm banana plugs, spade lugs or bare wire
- Wireless: dual-band Wi-Fi 5 (up to 802.11ac) on 2.4 and 5 GHz, Bluetooth 5.0 with SBC and AAC
- Power supply: external 20 V / 3 A, mains 100-240 V at 50/60 Hz
- Standby consumption: under 0.5 W
- Size (WxHxD): 206 x 55 x 153 mm, 176 mm including sockets
- Weight: 1.1 kg, power supply excluded
- Finishes: black, silver
