The DAC Box S2 + is a miniature digital-to-analogue converter based on the ESS9038Q2M chip: USB, coaxial and optical inputs, PCM as high as 32-bit / 768 kHz and DSD256 from the USB port, and an analogue RCA output to the amplifier.
DAC Box S2 +: what is inside
This is the converter to put between digital sources and an amplifier that has analogue inputs only. There are three inputs: an asynchronous type B USB with XMOS interface for the computer, an optical Toslink suited to a television, and a coaxial S/PDIF for a transport like the CD Box DS2 T. Optical and coaxial accept PCM up to 24-bit / 192 kHz, while USB passes PCM files as high as 32-bit / 768 kHz and DSD up to DSD256, in DSD over PCM mode.
At its heart is a 32-bit ESS Sabre ESS9038Q2M chip, served by a clock circuit designed by Pro-Ject that synchronises every internal oscillator and brings quoted jitter down to 100 femtoseconds. Around it work thin-film miniMELF resistors and organic polymer capacitors, on a gold-plated board with four layers. There are five digital filters to choose from on the front panel, and the maker additionally cites a filter of its own tuned for transients.
Noise travelling along the USB cable is filtered in two stages before it can touch the audio signal. The output is a pair of RCA sockets at line level. The aluminium and metal sandwich case screens out vibration and interference, and the external 5 V, 1 A power supply is part of the package. The published figures are 120 dB of dynamic range and distortion of 0.0007 %.
Specifications
- Type: digital-to-analogue converter (DAC)
- Dynamic range: 120 dB
- Digital inputs: USB type B, coaxial RCA, optical Toslink
- Converter chip: 32-bit ESS9038Q2M
- Formats over USB: PCM to 32-bit / 768 kHz, DSD to DSD256
- Formats on coaxial and optical: PCM to 24-bit / 192 kHz
- Digital filters: 5, chosen on the front panel
- Bandwidth: 20 Hz to 20 kHz
- Harmonic distortion: 0.0007 % (0 dB level, 2 V RMS, 1 kHz)
- Analogue output: one pair of RCA sockets
- External power supply: 5 V DC, 1 A, supplied
- Weight: 355 g, power supply excluded
- Size (width x height x depth): 103 x 37 x 122 mm with knob and sockets
- Finishes: black, silver
