SPDIF Digital In/Out

[Markaholic]

My question to the guru's of the BBS is about the spdif cable connections on my soundcard and on my interface.

Up until now ive pretty much got used to my setup and how things work...(enough to finally put all those nice "shiny new" boxes away)...and while i was putting them away...i forgot that my soundcard came with this spdif cable ,that has 1 digital In and 1 Digital Out that are both RCA's - plus midi in and out as well.
See below for a picture:
http://www.esi-pro.com/zoom.php?img=./upload/product/at010_cable_b.jpg

Now my question is...what are these used for ?(the digital In and Digital Out)
And is it possible to put it to some good use with my interface?...because it too has 2 RCA's that are Digital in/out as well.(jacks located @ top right corner)
See below for a picture:
http://media.zzounds.com/media/brand,zzounds/p21288H-9d19848cad92160c57cb390c187c197b.jpg

Now also...my card claims it has 10 ins and 10 outs...thus the name "AudioTerminal 010"...Now i imagine the R-Bus is taking up 8 ins for the Roland..but where are these other 2 ins supposed to be?...and most importantly...can i use it for say another DI'ed Instrument for a scratch track (because it just sucks for when im micing a big kit and wanna use all 8 tracks for the kit instead of 7 for the kit and 1 for the DI)...or possibly use it for exporting a mixdown to say....soundforge?(because the real time export just biffs when i use a few too many plugs)

Also here is a pic of what the audio properties for the card looks like:
http://home.comcast.net/~rakkasans101/audio.properties.JPG

Im sorry for the lengthy post...but im just trying to get to know my gear as best as possible so therefore i can use it to its fullest.

All info about the 2 things in question can be located here and thanks for any/all replies!
http://www.rolandus.com/products/details.asp?CatID=12&SubCatID=51&ProdID=SI-24
http://www.esi-pro.com/viewProduct.php?pid=7&page=1

 

[Jim Y]

A lot of pc audio interfaces have 10 i/o. 8 analog, ADAT or whatever and 2 in an s/pdif connection (optical or rca). Many pci cards use the same audio system chip (IC Ensemble Envy24 series) which can support up to 4 stereo channels + s/pdif, so they aren't having to be particularly clever to offer 10 mono channels.
So, yes the s/pdif coax is an extra 2 channels on the Esi card.

It looks like the Si24 coax s/pdif is tied to mixer channels 7/8 which must surely already be in the r-bus, though I'd have though it could also carry the main stereo output mix. What does the manual say?

 

[Markaholic]

It looks like the Si24 coax s/pdif is tied to mixer channels 7/8 which must surely already be in the r-bus, though I'd have though it could also carry the main stereo output mix. What does the manual say?

Damn PDF's dont let me copy and paste!
Heres a couple screenshots from the manual about these digital ins/outs:

http://home.comcast.net/~rakkasans101/untitled.JPG
http://home.comcast.net/~rakkasans101/untitled1.JPG

Now keep in mind...the RPC-1 is the card that came with some units...i however...bought the audioterminal 010 instead.But i imagine the same applys to this card

 

[Jim Y]

I don't think you can get an extra two inputs just by connecting this together. You'll need another piece of gear that has analog - digital s/pdif - Then you can try to see where best to connect and route the s/pdif in so you can monitor as well as record it, though if it's only for a guide track, you might just plug directly into the soundcard s/pdif and record it on faith on it's own stereo track with the 8 drums going through the r-bus channels to their own tracks.
You cannot directly mix seperate digital sources. The sample rate must be from an identical clock, not just the same setting. So the Si24 or Esi s/pdif out will feed the external units input and it must be set to use this rather than it's own clock (also called "word clock").

If you look on e-bay you might pick up a cheap Lexicon FX or older Roland VS recorder that can supply the s/pdif and lock to another incoming sample-rate (MPX500/550, VS880). Standalone converters are expensive (compared to gear that happens to have them anyway), though you might find an ART Dio cheap enough.

Assuming the Esi driver shows the s/pdif in as an extra record input in your software?

 

[Markaholic]

Assuming the Esi driver shows the s/pdif in as an extra record input in your software?

Yeah....10 seperate ins show up in my software....and in windows audio properties....it shows up like this:

AT010 1/2
AT010 3/4
AT010 5/6
AT010 7/8
AT010 Multi-10 CH
AT010 SPDIF-AC3 Out

Ill have to give running straight in for a scratch track a go.....how about the re-routing to soundforge idea?