A compact stereo preamplifier with a built-in D/A converter: it gathers analogue, digital and Bluetooth sources, an MM turntable and the television included, and feeds them to a power amplifier.
Pre Box S3: inputs and conversion
The Pre Box S3 is meant to be the control centre of a modern system in very little space. It has nine inputs: two RCA line inputs and a phono input for MM cartridges on the analogue side; coaxial, two Toslink optical, asynchronous USB-C, HDMI eARC for the television and Bluetooth 5.0 with aptX and aptX HD on the digital side. A turntable, a CD transport, a streamer and the TV can therefore share one unit, with source selection from the supplied remote control.
Conversion is handled by a Cirrus Logic CS4344 accepting signals up to 24 bit and 192 kHz, with careful internal clocking to keep jitter low. The analogue stage is a low-noise design with short signal paths, and the digital section is kept strictly apart from the analogue one so that noise from the former cannot reach the latter. The Italian distributor's list also mentions a dual mono layout and an all-aluminium chassis.
Round the back there is a variable-level RCA output for the power amplifier, a fixed output on a 3.5 mm mini-jack for an external headphone amplifier or a second zone, and an RCA output reserved for a subwoofer. The 6.3 mm headphone socket on the front suits models from 16 to 600 ohms. A 12 V trigger output switches partnering equipment on and off, and an RS232 port serves custom-installation control systems.
Specifications
- Frequency response: 20 Hz to 20 kHz within 0.4 dB
- Gain: 4.5 dB on line inputs, 45 dB on phono
- Channel separation: 72 dB at 10 kHz
- Signal-to-noise ratio: 110 dB (120 dB A-weighted)
- Harmonic distortion (THD): below 0.007%
- Headphone stage: 6.3 mm jack, 2 x 70 mW into 32 ohms, for 16 to 600 ohm headphones
- Analogue inputs: 2 RCA line and 1 RCA phono for MM
- Digital inputs: coaxial RCA, 2 Toslink optical, asynchronous USB-C, HDMI eARC, Bluetooth
- Bluetooth: version 5.0 with aptX and aptX HD (A2DP)
- DAC chip: Cirrus Logic CS4344, 24 bit / 192 kHz
- Outputs: variable RCA, fixed on 3.5 mm mini-jack, RCA for subwoofer
- Control: 12 V trigger output on 2.5 mm jack, RS232 on a 3-pole terminal block
- Power: 18 V / 500 mA DC from a 100-240 V mains adapter
- Standby consumption: below 0.5 W
- Dimensions: 206 x 55 x 153 mm (width, height, depth), 176 mm deep including sockets
- Weight: 1020 g, power supply excluded
- Finishes: black, silver
