Optical Digital or Coaxal Digital ???? Opinions

Bstage

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I have a Motif 6 looking to create the ultimate small production studio...

My goal is clear recordings of music to take to a larger studio to put vocals on.. As of right now I have a Audiophile 24-96 sound card, Aphex 107 Pre, AKG C4000B, lil rolls headphone amp, Midiman usb Midi 4 in, 4 out, no monitors with Sonar, Cubase, Logic, SoundForge and a few extras....

My question is what sound card can I take Digital (either coaxel or optical) audio into, record 8 tracks seperate into Sonar 2XL and mixdown with a external mixer all automated (move the slider Sonar jumps, Sonal jumps, Motif jumps..... USB, or RCA, 1-4 or digital ????? Ideas??

Motif 6 has 1 optical output with stereo pair. L/R output Assignable L/R...... There is an expansion board that is 260.00 that will add coaxel digital 1/2 and additional optical ins 1/2 outs 3/4.

Im looking for clean sound, minimal distortion, and maximum clarity and levels....

Thanks for reading this post
 
You have Sonar, Cubase, Logic, and SoundForge? Isn't that a bit expensive for software for a project studio?

Anyway, I don't know off-hand of any soundcards that can take more than a single digital (two channel) input. Are there any ways to multiplex several channels to a single S/PDIF? Dunno...
 
Bigus Dickus said:
Anyway, I don't know off-hand of any soundcards that can take more than a single digital (two channel) input. Are there any ways to multiplex several channels to a single S/PDIF? Dunno...
I run the RME 96/52 sound card. It's I/O is digital optical. It allows for 16 inputs on the main soundcard, and an additional 8 on the included "daughter board" for a total of 24 inputs.
 
IMNSHO, you should always go optical whenever you can. This helps prevent building in ground loops by connecting two chunks of gear together with coax. The shield in the coax may or may not short chassis grounds together, giving the potential for a loop. Why take the exposure?

Think of the optical cable as a free isolation transformer. Chasing ground loops out of a complex setup is a full-time chore, so anything that you can reasonably do to avoid them outright is a win!
 
I thought coax s/pdif includes ground isolation?
Multi channel cards usually use the 8track ADAT digital i/o - digital mixers usually have this or as an option.
No, you won't get a multichannel digital i/o on seperate s/pdif, coax or optical, because each s/pdif channel carries it's own audio timing signal and any system can only have one unless it uses a sample-rate converter on every one - the pro interfaces use a seperate coax feed called word clock that keeps everthing at the same sample-rate.
I would think hard before spending on a digital desk - if you like to see faders moving by themselves, well that's fine - but it can't be better than editing mix envelopes in the DAW which you'll probably end up doing when fine tuning your mix.
I remember reading a Sony hi-fi atricle that stated that Coax had better timing stability than optical. S/pdif stands for Sony/Philips digital interface so do you believe it?
But I prefer coax because I can make one up if needed with ordinary 75ohm video cable with rca plugs. Not so simple to make an optical cable.
 
Like I said: it may or may not short the chassis together. S/PDIF is indeed *supposed* to be isolated, but on low-end gear- who knows? Maybe it is, maybe it isn't! Most likely, on low end stuff the coax shield is just tied to the ground supply for the logic: I have a couple examples of that laying around (one of which is a Sony low-end MD deck).

With optical, it ain't-a-gonna make a ground loop, no matter how well or badly designed the gear in question is.

Jitter is another matter entirely, of course. S/PDIF doesn't have nearly the problems with jitter that ADAT lightpipe does: the data rate is 4x higher for ADAT (8 channels), and if you look at the specs for the TOSlink transmitter and receiver pairs, you'll see that 8 channels of 24-bit audio at 48kHz is about 125% of the max rated speed for the hardware. I posted the link to those data sheets a few months back- do a search for them on the site here. In any case, jitter is much more of an issue with ADAT lightpipe since it is being used so far outside its design envelope, and you'll rapidly find yourself forced to go with a central word clock generator if you try to do anything more complex than simple point-to-point interconnect.

I think that for S/PDIF stereo, the two connection types give very sonically similar results (although no doubt there are golden ears who are passionately convinced that one or the other is better). I can't hear it- but I sure as hell _can_ hear ground loops! So I fix what I can... Your mileage may vary: use either one in good health, and with my blessings.
 
Michael Jones said:
I run the RME 96/52 sound card. It's I/O is digital optical. It allows for 16 inputs on the main soundcard, and an additional 8 on the included "daughter board" for a total of 24 inputs.

oooohhh, that sounds interesting. Now I'll have to do a bit of googling before I go to bed. :(

:)
 
Yep, optical avoids groundloops, it has more jitter and you can forget to make cables. Also soundcards with optical spdif are a bit more difficult to find.

The rme can use optical spdif on its first adat i/o. But it is optical or coax, not both. While on the subject of rme: if you are on their website, check out the adi-8 dd. It is a convertor for 4x aes to adat. (you can convert optical spdif to coax spdif and connect that to aes). Oh, and if you ever fancy more, up to 3 rme's can be used together for 76 IO's.
 
Thats a Soundcard

Bigus Dickus said:
oooohhh, that sounds interesting. Now I'll have to do a bit of googling before I go to bed. :(

:)


24 inputs is not bad, wonder if the old CPU can handle the load.......... Nubb off the old Paycheck though....
 
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