CS8412, PMD100, PCM63, onboard clock + [word] clock output implementation

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I’m trying to connect my PC sound card with word clock input to external DAC and get best sound possible. I think that appropriate solution is to install low jitter clock into DAC and feed soundcard and CD transport from it.
The DAC is Parasound DAC1600 (CS8412->PMD100->4*PCM63P-K). Transport is Parasound CDP1000 (AKA CEC 2200). What should be done to implement this? I’m lost in external clocking of CS8412 + PMD100, please advice.

Thanks,
Victor
 
I don't think all those PLLs and VCXOs are required in this case. Just implement a good quartz oscillator in the DAC. This will have far less noise than any VCXO. Use an 8-bit counter to output the word clock every 64th edge of the main clock, and output this signal on BNC to your sound card.

I haven't seen many PC sound cards with this ability. What kind is it?
 
jwb said:
I don't think all those PLLs and VCXOs are required in this case. Just implement a good quartz oscillator in the DAC. This will have far less noise than any VCXO. Use an 8-bit counter to output the word clock every 64th edge of the main clock, and output this signal on BNC to your sound card.

I haven't seen many PC sound cards with this ability. What kind is it?


So jwb, how many transports are you aware of with a system clock of Fs?
BTW, are you aware that wordclock reference is Fs?
 
Well it doesn't really matter. You can either 1) output the Fs to the CD player and multiply it by 64 to get the master clock, or 2) output the master clock directly from the DAC to the CD player. You still don't need PLLs and VCXO's. I see no reason to try to use two clocks with a lot of circuitry to keep them syncronized. All you need is a low-jitter master clock driving the DAC, and the same clock driving all the other gear.
 
jwb said:
Well it doesn't really matter. You can either 1) output the Fs to the CD player and multiply it by 64 to get the master clock, or 2) output the master clock directly from the DAC to the CD player. You still don't need PLLs and VCXO's. I see no reason to try to use two clocks with a lot of circuitry to keep them syncronized. All you need is a low-jitter master clock driving the DAC, and the same clock driving all the other gear.

Oh, but it does matter.
Lets start with the dac. The dac in question uses the CS8412 and that makes master clock (MCLK) 256Fs not 64Fs, nevermind the fact that the SM5842 will not get out of bed for anything other than 256 or 384 Fs.
Then there is already present clock domain, the 256Fs one derived by the CS8412 from the SPDIF datastream. Attempting to add a second standalone XO domain without due care and attention would not be wise. One would have to synchronize the two domains for the system to work properly.
Now to the transport. It is just as likely to run at 256Fs as at 384Fs but probably not 64Fs, so simply sending MCLK across may not suffice. Now if you could just point me in the direction the clock multiplier that does not use a PLL or its digital equivalent.
 
It's incredible what you can find out on your on hard drive. I found schematics of what I want: I put it there in WMF and MS Word foramts. Do you see any flaws in it, except clock schematics (I will use KC-7, probably)?

jwb said:
I don't think all those PLLs and VCXOs are required in this case. Just implement a good quartz oscillator in the DAC. This will have far less noise than any VCXO. Use an 8-bit counter to output the word clock every 64th edge of the main clock, and output this signal on BNC to your sound card.
That are exactly my thoughts :)

I haven't seen many PC sound cards with this ability. What kind is it?
You have to look at pro and "prosumer" range of soundcards. Examples are Lynx AES16 or Two and ESI Juli@
 
jwb said:
Well it doesn't really matter. You can either 1) output the Fs to the CD player and multiply it by 64 to get the master clock, or 2) output the master clock directly from the DAC to the CD player. You still don't need PLLs and VCXO's. I see no reason to try to use two clocks with a lot of circuitry to keep them syncronized. All you need is a low-jitter master clock driving the DAC, and the same clock driving all the other gear.
My CDP uses 386*Fs clock, and DAC 256*Fs clock. This is the reason for PLL to exist, but I think clock for DAC and PLL for CDP is more appropriate
 
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