Lcpm Vs Ac3

Discussion in 'AnyDVD HD (Blu-ray issues)' started by vamsilak, May 25, 2008.

  1. vamsilak

    vamsilak Well-Known Member

    hi guys
    which one better Lcpm or Ac3
    iam using Tsmuxer in some movies i can see the lcpm 5.1
    and ac3 6 channels
    i wonder which one better
    thankyou for the help in advance
  2. Jong

    Jong Well-Known Member

    LPCM is the best by far. Lossless and does not need a decoder.

    But you have to have a way of getting it to the speakers. If you have an AV amp that can be tricky. You cannot use your s/pdif port, unless you re-encode as AC3 or DTS, losing most if not all the benefit.
  3. vamsilak

    vamsilak Well-Known Member

    thanku guys
  4. Tanquen

    Tanquen Well-Known Member

    How about True-HD vs LPCM? tsMuxeR says True-HD is 640Kbps and LPCM is 4608Kbps? Is that true? Whould they both sound the same just True-HD has better compresion?
  5. Jong

    Jong Well-Known Member

    They should have the same result, because TrueHD is lossless compression (a bit like a zip file, it saves wasted space but does not clip any of the original sound). Don't know why tsMuxer says 640kbps because that is almost certainly wrong, but it will be lower than LPCM.

    The only potential problem is that TrueHD has to be decoded. First, of course, there can be bugs in the decoder. Unlikely now as the decoders are quite mature, but possible. More of an issue, for some, is it takes quite a bit of processing power to decode it (unless you pass it as a "bitstream" to a compatible AV amp). Depending on your CPU this can affect the smoothness of playback. Lastly, on the subject of "bitstreaming", LPCM can be sent to almost any HDMI 1.1 or greater AV amp. TrueHD needs HDMI 1.3 and an AV amp with TrueHD support for bitstreaming. Alternatively it must be decoded on the PC first (with the resulting CPU performance penalty).