Createive x-fi expresscard multichannel

Discussion in 'Tech Support' started by Splynncryth, 19 Mar 2009.

  1. Splynncryth

    Splynncryth 0x665E3FF6,0x46CC,...

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    I have a SB0710 express card sound card for my laptop. I have finally gotten around to getting some proper multichannel speakers that I am connecting via an optical jack. I cannot get anything from any speakers other than the front left and front right speakers. I can't find a magic button that says "enable multi channel support". I have tried every speaker setup above 2.1 (which are 4.1, 5.1 and 7.1).
    The speakers are connected via the optical output and I do not have their analog multichannel dongle (didn't figre I needed it with TOSLINK).

    Am I yet another consumer stiffed by creative, or is there something I have overlooked?
     
  2. azrael-

    azrael- I'm special...

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    S/PDIF, whether via optical or coaxial cable, can only stream a stereo PCM signal. The only way to get multi-channel audio over S/PDIF would be to stream previously encoded (DD/DTS) multi-channel audio and that, in turn, requires a decoder on the other end of the stream.

    In short, if you want to get multi-channel audio from your sound card you need to connect your speakers to your sound card with an analog connection.

    Oh, and you're not getting stiffed by Creative on this; it's just how S/PDIF works. :)
     
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  3. Splynncryth

    Splynncryth 0x665E3FF6,0x46CC,...

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    It handles the optical surround data from my 360, DVD player, and digital TV tuner just fine. I intend to double check if my old nForce board's Soundstorm would play the test audio through all the speakers using an optical connection as well.

    I did some more digging after my frustration had died down, and it may have something to do with AC3 encoding, but I have not seen any options for that.
     
  4. azrael-

    azrael- I'm special...

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    Well, if you get multi-channel audio from your 360 it's because it is already encoded in DD (AC3) or DTS. S/PDIF as such cannot transport anything other than PCM stereo. You'd have to find some sort of e.g. AC3 encoder to encode your multi-channel audio before sending it to your sound card. You might want to give this a try, although I don't know if it works.
     
  5. Splynncryth

    Splynncryth 0x665E3FF6,0x46CC,...

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    I'll give it a try.
    What bugs me is that this is not mentioned in the Creative material, and I expected at least the sound test to to drive all the speakers.

    As a point of comparison, I tried my old nForce based system connected via TOSLINK and it didn't have a problem driving each speaker for the sound test, and the environmental effects the driver support will utilize all the speakers in a 5.1 setup.
    So if an old socket A based board did it, I assumed that it would be common practice on modern hardware. Apparently, I am mistaken.

    Creative has had a number of problems the past few years to upset their consumers, so I am concerned that they may not all be resolves. I have been using their products since my first computer many years ago when cards were still marketed as sound blaster compatible, and you needed to know arcane letter/number strings like A220 I5 D7.
     
  6. azrael-

    azrael- I'm special...

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    The reason your old nForce-based motherboard can do it is because it could encode multi-channel audio into an AC3 stream in hardware before sending said stream over S/PDIF. I remember people being pretty miffed when nVidia dropped the AC3 hardware encoding. It started with the A64 chipsets, if I remember correctly.

    I need to once more stress that *this* particular issue has got nothing to do with Creative (although they can be blamed for much else :)). It's just how S/PDIF (Sony/Philips Digital Interface) works.
     
  7. Splynncryth

    Splynncryth 0x665E3FF6,0x46CC,...

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    OK, so I was just spoiled by me previous system :)

    I will have to keep this in mind when I start shopping for parts for a new syste or a new laptop.
     

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