24 bit / 96 (or even 192) kHz question...

Discussion in 'Archived Threads 2001-2004' started by Kevin C Brown, Jan 8, 2002.

  1. Kevin C Brown

    Kevin C Brown Producer

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    A lot of the newer receivers and pre/pros use 24/96 (192) DACs.
    Obviously better than 16/44.1 or 16/48.
    But, I would assume that for the best sound from CD, best to either leave it as 16/44.1, or to simply upsample to 16/88.2 or even something like 24/176.4.
    But if you *re-sample* the incoming 16/44.1 to say 16/96 or 24/192, there *could* be an affect on the sound quality, right?
    All I remember, is that for DAT, which inherently is 16/48, but then linear PCM (CD) is 16/44.1, it was always said that for the *best* sound quality, do *not* do any rate *conversion*.
    Just curious what others thought about this or knew as fact.
    As always, ... Cheers! [​IMG]
     
  2. Jaehoon Heo

    Jaehoon Heo Stunt Coordinator

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    I assume that delta-sigma type DAC is used. In this case,

    most incoming PCM's are upsampled to 8x speed (256~384kHz), and then noise-shaped to fewer-bit PDM(mostly) or PWM. In many delta-sigma DAC's, upsampling FIR doesn't have excellent characteristics, and DVD players' DSP can do better upsampling. However, you may guess that better upsampling is not guaranteed, and it would be really hard to tell, because it is the S/W difference.

    The one thing that should be cared is the upsampling to a fixed frequency. If CD 44.1kHz PCM is upsampled to 96/192kHz, I don't think it will produce good output. Upsampling by non-integer ratio like 192/44.1 would impose much more artifact than by upsampling by integer ratio. I believe 176.4kHz or 88.2kHz are the right upsampled sampling rate for CD audio.
     
  3. Charles L.

    Charles L. Agent

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    Thanks Jaehoon

    I should have read that reply backwards. I would have understood more of it that way. understand can I so time more one that say you can
     
  4. Kevin C Brown

    Kevin C Brown Producer

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    Jaehoon- Cool, that's what I obviously thought too.

    A better way to put it is:

    Up-sampling (44.1 to 88.2, etc) may give you better sound quality.

    Re-sampling (44.1 to 96, etc) will probably degrade the sound quality.
     

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