Alrighty A 8. Thanks for clearing that up. I was thinking it through in my head today and figured how ridiculous it was.
How about if I feed the PCM1794 the master clock and send that to the CD player, if they're the same frequency. Would that be a better idea? (not to mention can I stick with the 16.9344 MHz clock?)
~Tom
How about if I feed the PCM1794 the master clock and send that to the CD player, if they're the same frequency. Would that be a better idea? (not to mention can I stick with the 16.9344 MHz clock?)
~Tom
Ok I'm all clear now. Is there anything wrong with doing it the opposite way such as using the pre-existing clock in the cdplayer and feeding it through to the DAC without any sample rate converting? Other then the obvious line induced jitter ofcourse 
.
As a matter of interest is the MCLK line in the I2S signal identical to the crystal used in cd/dvd players?
. As a matter of interest is the MCLK line in the I2S signal identical to the crystal used in cd/dvd players?
Poor man's Word Clock is basically what this is, right?
Is it possible to use a S/PDIF clock to drive a video capture card?Or vice versa? I found this thread because I was trying to think of a way to jerry rig a S/PDIF sound card input to sync up with the clock on a video capture card to eliminate drift between the audio and video portions of my video transfers to digital.
I'm running an LD player --->RF to S/PDIF converter box -->Soundcard + Video capture cards.
The nature of the digital audio signal (AC3) would necessitate that the digital input of the sound card (which is a bit accurate M-Audio 2496 btw = no resampling of digital bitstream) would lock to the incoming S/PDIF clock signal. What I want to do is lock the video capture card clock to the same signal. This discussion seems quite close to my own ideas. The intended result is kind of like a poor man's word clock, right?
Has anyone ever reclocked or resync'ed a PCI card to another source before? I know there was a page somewhere on the web about reclocking an AC97 sound chipset on a motherboard.
Here it is: http://www.lcaudio.com/index.php?page=66
Is this helpful to anyone? I'm definitely going to have to read up on some of the suggested subjects to get up to speed, but perhaps someone can give me a "Hell yeah" if this is not too outlandish an idea.
-Erik
Is it possible to use a S/PDIF clock to drive a video capture card?Or vice versa? I found this thread because I was trying to think of a way to jerry rig a S/PDIF sound card input to sync up with the clock on a video capture card to eliminate drift between the audio and video portions of my video transfers to digital.
I'm running an LD player --->RF to S/PDIF converter box -->Soundcard + Video capture cards.
The nature of the digital audio signal (AC3) would necessitate that the digital input of the sound card (which is a bit accurate M-Audio 2496 btw = no resampling of digital bitstream) would lock to the incoming S/PDIF clock signal. What I want to do is lock the video capture card clock to the same signal. This discussion seems quite close to my own ideas. The intended result is kind of like a poor man's word clock, right?
Has anyone ever reclocked or resync'ed a PCI card to another source before? I know there was a page somewhere on the web about reclocking an AC97 sound chipset on a motherboard.
Here it is: http://www.lcaudio.com/index.php?page=66
Is this helpful to anyone? I'm definitely going to have to read up on some of the suggested subjects to get up to speed, but perhaps someone can give me a "Hell yeah" if this is not too outlandish an idea.
-Erik
No Reference
rfbrw
No, unfortunately, I'm using a consumer level video capture card, the Sapphire Theatrix with ATI's Theater 550 Pro chip. It's only got analog audio and video inputs. The audio card is an M-Audio Delta 2496. It has S/PDIF input. It's my understanding that the incomng digital signal carries a clock along with the data stream, and the card may then slave to that clock signal for bit-accurate recording. However, my problem is figuring out how to get the video capture card clock to march in step with that same clock signal the audio card is syncing to.
Hope this clarifies it a bit.
-Erik
rfbrw
No, unfortunately, I'm using a consumer level video capture card, the Sapphire Theatrix with ATI's Theater 550 Pro chip. It's only got analog audio and video inputs. The audio card is an M-Audio Delta 2496. It has S/PDIF input. It's my understanding that the incomng digital signal carries a clock along with the data stream, and the card may then slave to that clock signal for bit-accurate recording. However, my problem is figuring out how to get the video capture card clock to march in step with that same clock signal the audio card is syncing to.
Hope this clarifies it a bit.
-Erik
Not Cost Effective? Are you certain?
RFBRW, I'm sorry, but I'm not convinced of that.
No disrespect intended, of course, but you must realize the astronomical cost of professional level analog video capture cards with word clock inputs. You simply cannot buy one for less than 2 grand the last time I looked. The investment of some time and a little money to build an external clock circuit like the XO3 or something similar, and reference the two cards to it shouldn't be prohibitive by comparison, no? I have little experience in digital electronics, but I know enough to know that it isn't black magic, and for someone with a little dedication, it shouldn't be impossible.
There are plenty of folks who have reclocked their CD/DVD players and other digital devices using DIY and aftermarket circuits. It consistently produces superior results to most retail products, and certainly is more cost effective than buying retail priced pro gear implementing the same high end technology.
I appreciate that you took the time to respond, RFBRW, but I'm not giving up that easily.
I'm still open to any suggestions folks might have.
-Erik
RFBRW, I'm sorry, but I'm not convinced of that.
No disrespect intended, of course, but you must realize the astronomical cost of professional level analog video capture cards with word clock inputs. You simply cannot buy one for less than 2 grand the last time I looked. The investment of some time and a little money to build an external clock circuit like the XO3 or something similar, and reference the two cards to it shouldn't be prohibitive by comparison, no? I have little experience in digital electronics, but I know enough to know that it isn't black magic, and for someone with a little dedication, it shouldn't be impossible.
There are plenty of folks who have reclocked their CD/DVD players and other digital devices using DIY and aftermarket circuits. It consistently produces superior results to most retail products, and certainly is more cost effective than buying retail priced pro gear implementing the same high end technology.
I appreciate that you took the time to respond, RFBRW, but I'm not giving up that easily.
I'm still open to any suggestions folks might have.
-Erik
Adding an XO3 or something similar to a CD/DVD is very simple. Sync'ing three devices, all in different clock domains, is somewhat harder. To further complicate matters, the LD player has a RF output. Replacing the clocks in all three devices with sync-capable versions is no small matter, particularly if you have to design said clocks from scratch. True, it will not cost $2000 but it will take a lot more than adding a flip flop or two to the data lines.
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