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3 Days And Still No 5.1

By Topper Harley
Mar 4, 2006
  1. Hello all, here is my thang....

    I have an Asus P4PE motherboard with onboard 5.1 surround sound capabilities and SoundMax audio utility. I have installed the Spdif module (digital audio connector) and are running a digital optical cable to my Samsung 5.1 surround receiver.

    The problem is here.........when I use the SoundMax software utility to test the presence of all 5 speakers, only the front 3 are functioning. Basically as the sound moves through each speaker in a circle but no sound comes from the rears????

    I have windows set to 5.1 speakers, AC3 checked on and PCM checked on in the audio properties, and the latest SoundMax for my MB. By the way the receiver is working properly because I can phase all 5 speakers within the receivers' own utility. ANY IDEAS?????
     
  2. hewybo

    hewybo TS Maniac Posts: 435

    output

    Are you sure whatever media you are playing is outputting a 5.1 signal? Unless your sound card/syatem has a simulated surround, which just sends the front signals to the rear as well, a stereo CD will only send a stereo signal, regardless of the hookup. :)
     
  3. Mictlantecuhtli

    Mictlantecuhtli TS Evangelist Posts: 4,345   +11

    The receiver needs to receive digital 5.1 sound in a format it understands. Mostly it's either Dolby Digital (a.k.a. AC3) or DTS. It would be simple if it was just analog audio with three or four cables, but digital audio is always in one format or another.

    In other words, you need to have a realtime AC3 or DTS encoder in your PC if you want to transmit 5.1 audio through S/PDIF.

    DVD movies and such are another matter because the audio is already in correct format, it's just a matter of transmitting it.
     
  4. seanp789

    seanp789 TS Enthusiast Posts: 111

    Mictlantecuhtli is correct.

    To rephrase it...

    -The reason you "hear" the front 3 channels is because when it "plays" the center channel, it is actually just using both right and left making it sound like it is coming from the center.

    -The AC3 you have checked, is either AC3 bypass(what you want) or AC3 decode so even if you played a movie from your PC, it woudl still only come out as stereo and not 5.1. You can test this by simply putting in a movie. If you get surround then its correct, if u do not then change it.

    Your soundcard is in fact only sending a stereo(2 channel) PCM digital signal. therefore you will not receive 5.1 sound unless it is transfered via anlaog cables or is encoded properly as in movies that Mictlantecuhtli mentioned.


    I hope that answered your question.
     
  5. Topper Harley

    Topper Harley TS Rookie Topic Starter

    Thanks for the explanations guys, I got my Dvd movies to pass through the Sdif and give me Dolby Digital surround like you said. However the Soundmax utiliy still won't phase the rears, I guess because Soundmax is in analog mode and my receiver won't detect it.

    What exactly I've been trying to do is get Half Life 2 to play in Surround sound through the Spdif and into my reciever (via optical) is Half life 2 dolby digital ? Should my receiver not pick up the dobly signal as such?
     
  6. Mictlantecuhtli

    Mictlantecuhtli TS Evangelist Posts: 4,345   +11

    No, HL2's surround sound isn't Dolby Digital format. I guess it just uses DirectSound, that's all.

    You'd need a filter between applications (games) and the output, a software AC3 encoder like redocnexk.
     
  7. Topper Harley

    Topper Harley TS Rookie Topic Starter

    Great Thanks, for help brotha's
     
  8. seanp789

    seanp789 TS Enthusiast Posts: 111


    Great find Mictlantecuhtli. I'm gonna test this out see what kind of cpu usage and quality it provides.
     
  9. seanp789

    seanp789 TS Enthusiast Posts: 111

    a little extra research...

    This is not a simple download and run tool I was hoping for.


    This is intended for use with KXaudio drivers and a software DSP controller.It works with audigy series cards.

    It does not appear to work on an X-Fi at this time. If someone else has gotten this working , please post.

    more information can be found here...
    http://www.driverheaven.net/showthread.php?t=90887
     
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