Of course those in the know will waffle on about jitter and how S/PDIF, which embeds the clock signal in the same stream as the audio information, isnâ€™t the best means for getting the cleanest digital signal into your DAC circuitry. That may well be the case, but if youâ€™re still sceptical, take note of the following salutary taleâ€¦
I have, for my sins, a reasonably expensive hi-fi setup at home. The star of the show is a hand-built, Italian designed CD player â€“ a Unison Research Unico CD. It cost me Â£1,200, plus Â£180 for a cable upgrade, sounds wonderful and the hi-fi press agrees.
Anyway, out of curiosity I opened it up one day and made a surprising discovery. Behind that expensive, sand-blasted aluminium fascia sat a CD-ROM drive. Yep the sort of drive you might find in any modern PC (albeit slightly modified) was acting as the transport in my boutique music system.
With the lid off my expensive valve-drive Unison Research Unico CD player I was shocked to find that the source of the digital signal came from the S/PDIF TTL output on a modified ASUS CD-ROM drive.
The business end of the player â€“ the valve-powered DAC electronics â€“ simply takes the S/PDIF signal straight from that drive via a two pin TTL connection, before turning it into analogue audio.