SPDIF help

[Bluewater]

I'm assuming I'll get better audio quality using the SPDIF connector from my ToneLab to my AudioFire interface, since this avoids a DA/AD conversion. Assuming this is true (is it?), and given that the ToneLab has an optical connector and the AudiorFire has RCA, where can I find a convertor/adapter cable to connect these two devices?

 

And why isn't there one standard for S/P DIF, for cryin' out loud?

[Phil O'Keefe]

You need something like one of these.

 

About $80 list.

 

Why is there two standards - optical and coax? Beats the heck out of me.

 

Yes, that should sound better, since you will be avoiding a couple of converter stages.

 

Make sure you set your computer soundcard's word clock setting to "S/PDIF slave" so that you don't have any word clock related issues.

[Bluewater]

Originally posted by Phil O'Keefe You need something like one of these. About $80 list. Why is there two standards - optical and coax? Beats the heck out of me. Yes, that should sound better, since you will be avoiding a couple of converter stages. Make sure you set your computer soundcard's word clock setting to "S/PDIF slave" so that you don't have any word clock related issues.

 

Thanks Phil; somehow knew you'd have the answer.

 

You can probably expect a question on word clock issues at some point, because I've managed to avoid dealing with that aspect of the digital domain so far..................

[Phil O'Keefe]

Well, if that becomes an issue, feel free to ask! The main thing to remember is that all digitally connected devices need to share a single, common word clock source - IOW, one device has to be the WC master and all other digitally interconnected devices have to be WC slaves of that master word clock source.

 

There should be a clock source button or menu on your sound card applet... just make sure it's set to "slave" when you're feeding S/PDIF digital audio into your soundcard and you should be good to go. Oh yeah, make sure you have the sample rates (IOW 44.1 kHz / 48 kHz or whatever) also set properly for each device - they need to be set to the same rate.

 

If you have any problems, please let me know.

 

[Bluewater]

Originally posted by Phil O'Keefe Well, if that becomes an issue, feel free to ask! The main thing to remember is that all digitally connected devices need to share a single, common word clock source - IOW, one device has to be the WC master and all other digitally interconnected devices have to be WC slaves of that master word clock source. There should be a clock source button or menu on your sound card applet... just make sure it's set to "slave" when you're feeding S/PDIF digital audio into your soundcard and you should be good to go. Oh yeah, make sure you have the sample rates (IOW 44.1 kHz / 48 kHz or whatever) also set properly for each device - they need to be set to the same rate. If you have any problems, please let me know.

 

Thanks again, Phil. My AudioFire had "internal," "spdif," and "word" options, so I assume it's the spdif that I should select in this case. Once I get the convertor, I'll confirm that it works -- hope the $59 price is worth the increase in audio quality... From what I can tell so far, nothing beats a mic'd amp.

 

And I can understand the necessity for digital devices to have a single clock for midi, but if I'm going to play a guitar using the ToneLab, thru the AudioFire to multi-track with a pre-recorded loop of drums on Sonar for example, why do the digital clocks need to be sync'd/

[Phil O'Keefe]

Thanks again, Phil. My AudioFire had "internal," "spdif," and "word" options, so I assume it's the spdif that I should select in this case.

 

Correct. I'm kind of surprised that your card has a "word" option - it must have a dedicated Word Clock input jack (usually a BNC type connector), and not all soundcards do. But yes, since the word clock data will be traveling over that same S/PDIF cabe as the digital audio (from your Vox), that's the setting to use.

 

Once I get the convertor, I'll confirm that it works -- hope the $59 price is worth the increase in audio quality... From what I can tell so far, nothing beats a mic'd amp.

 

You may still feel that way after you do the digital connection... but OTOH, it should sound better than using the analog connections.

 

And I can understand the necessity for digital devices to have a single clock for midi, but if I'm going to play a guitar using the ToneLab, thru the AudioFire to multi-track with a pre-recorded loop of drums on Sonar for example, why do the digital clocks need to be sync'd

 

Don't confuse MIDI sync with Word Clock sync - they're two different things. The WC sync is to make sure that the two devices are running at EXACTLY the same clock speed... even a slight variance between the two clocks will cause pops and clicks in the digital audio, and the ONLY way to avoid that is to make sure they are sharing a common word clock. That way, the digital samples will "line up" properly and you'll avoid those nasty clicks and pops in your audio.

[Bluewater]

Originally posted by Phil O'Keefe Thanks again, Phil. My AudioFire had "internal," "spdif," and "word" options, so I assume it's the spdif that I should select in this case. Correct. I'm kind of surprised that your card has a "word" option - it must have a dedicated Word Clock input jack (usually a BNC type connector), and not all soundcards do. But yes, since the word clock data will be traveling over that same S/PDIF cabe as the digital audio (from your Vox), that's the setting to use. Once I get the convertor, I'll confirm that it works -- hope the $59 price is worth the increase in audio quality... From what I can tell so far, nothing beats a mic'd amp. You may still feel that way after you do the digital connection... but OTOH, it should sound better than using the analog connections. And I can understand the necessity for digital devices to have a single clock for midi, but if I'm going to play a guitar using the ToneLab, thru the AudioFire to multi-track with a pre-recorded loop of drums on Sonar for example, why do the digital clocks need to be sync'd Don't confuse MIDI sync with Word Clock sync - they're two different things. The WC sync is to make sure that the two devices are running at EXACTLY the same clock speed... even a slight variance between the two clocks will cause pops and clicks in the digital audio, and the ONLY way to avoid that is to make sure they are sharing a common word clock. That way, the digital samples will "line up" properly and you'll avoid those nasty clicks and pops in your audio.

 

Got it, thanks Phil