Win Simple toslink passthrough / bitstream question
#1
I've searched and read through a ton of posts, but my question is very simple, and hoping for a very simple clarification. I feel like the more I read, the less I understand...

I have an Optical Audio jack on my sound card (toslink), plugged into my new Onkyo surround sound receiver (7.1). I set XBMC to passthrough the audio. When I play a movie with surround sound, the receiver clicks and displays the audio format (DD, DTS, etc..) I am getting proper surround sound on all my speakers and the movie sounds fantastic. I can literally hear the distinct sounds being played in each speaker properly. My understanding was that this is the proper way to set it up. Whatever the audio format is in the movie, XBMC doesn't care; it just sends it to the receiver to do the work. I'm not losing anything in this setup.

Right?

So what is "bit streaming HD audio", and why do I need to care about it? There is SO much conversation about it and I feel like I'm missing something. Am I not bit streaming HD audio in this case? If I am passing video through HDMI and audio through TOSLINK, then I'm good to go right?

Huh
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#2
Q for you: Are you 100% certain you are not ALSO passing audio via HDMI?

A for you: TOSLink can NOT bitsream the HD Audio codecs - DTS HD, Dolby TrueHD. It of course handle DTS and AC3, however, in that case I believe it's also limited to 5.1 channels.

Bitstreaming in itself simply means that the original audio track is passed onto the Receiver which then does the decoding - the Receiver will display format it is using at all times. When the decoding of DTS, AC3 or HD audio is done on a PLAYER it'll typically pass that audio onto the Receiver as LPCM and lots of them then display 'Multichannel In' or something similar.

If you are trying to play an HD audio track without bitstreaming support in XBMC enabled - new Audio Engine or external player - it'll play TrueHD --> LPCM, DTS HD --> core DTS track. Long story short is that if you have rips with HD audio keep them - if you can't support bistreaming on them now XBMC will eventually...
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A bunch of XBMC instances, big-ass screen in the basement + a 20TB FreeBSD, ZFS server.
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#3
Thank you!

For the first question, yes, I'm sure I'm not also passing HDMI audio.

Second part: Ok, that is making more sense. Even though I am getting DTS / 5.1 surround on my receiver, it sounds like it is not considered "HD Audio". I think I misunderstood that those are actually specific codecs. I thought anything "surround" was considered "HD". DTS is not the same as DTS-HD.

I must only be playing DTS at this point, since that's what the receiver is saying. So I'm missing out on the newer codecs.

-------

And the deal now is that I have to do this with a video card, not a discreet sound card. Right?
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#4
No problem.

(2012-10-17, 22:30)h1r0pr07ag0n1st Wrote: And the deal now is that I have to do this with a video card, not a discreet sound card. Right?

Yes - you haven't said what type of vid card, etc you are using, but all the modern vid cards nowadays pass both the vid + audio over HDMI...you may be able to ditch the TOSLink depending on what you are running.

If I helped out pls give me a +

A bunch of XBMC instances, big-ass screen in the basement + a 20TB FreeBSD, ZFS server.
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#5
Oh, it's a GT240, which doesn't seem to support any form of bit streaming. That makes sense now, because when I tried to use HDMI-only and play a movie, I got no sound at all. Ha! Makes total sense now.


(2012-10-17, 22:33)thethirdnut Wrote: No problem.

(2012-10-17, 22:30)h1r0pr07ag0n1st Wrote: And the deal now is that I have to do this with a video card, not a discreet sound card. Right?

Yes - you haven't said what type of vid card, etc you are using, but all the modern vid cards nowadays pass both the vid + audio over HDMI...you may be able to ditch the TOSLink depending on what you are running.

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#6
Actually your GT 240 will DEFINITELY support all the major 5.1 or 7.1 codecs - see my XBMC2 setup below. It likely will also support HD audio...however, all this needs to be configured correctly.

If I were you I'd take a step back and get the sound over HDMI sorted. http://wiki.xbmc.org/index.php?title=Set...dio_output

It sounds like your video card + receiver are capable of it.

Good Luck
If I helped out pls give me a +

A bunch of XBMC instances, big-ass screen in the basement + a 20TB FreeBSD, ZFS server.
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