Adding Wordclock inputs to source

[mlihl]

Hi,

I want to learn how to add a BNC Wordclock input to a transport such as a soundcard, CD player or Squeezebox? How would this work?
Simply replacing the original crystal oscillator and leading a shielded cable out?

Assuming I have a very stable, low-noise clock near my DAC - when I synchronize my sources with this clock, I would dramatically reduce jitter and this would be the perfect choice for a "clean" system as opposed to using ASRC's which are obviously only a poor choice for a low jitter system. Is this correct?

Maybe someone can shed some light on this or point me to some threads or reference sources so I can learn more about this.

Thanks,

Mike

[Guido Tent]

Hello Mike

You'd need a PLL circuit to go from 44.1 KHz to the original crystal frequency.

best

[Alexandre]

Hi.

One alternative is to buy a pro soundcard with wordclock i/o. A very good one is the RME Digi96/8 PAD with the WCM expansion.

Another way of implementing the system is to send the master clock directly to the transport, preferably using an optical interconnect. I´m not sure if the standard toslink transmitters and receivers can handle 11.2896 MHz or higher, please check that.

The third and best way (IMO): in the DAC, use a spdif tx IC to generate spdif with your clock. You can use any soundcard with spdif i/o as your transport. Or you can slave your cdplayer by adding a spdif rx to recover the 11.2896 MHz (if the MCK of your CDP is 256fs).

This last method is how I did it and it works flawlessly. I used optical interconnects and my soundcard is the RME Digi96/8 PST.

Best regards,
Alexandre