DAC that can convert PCM to DSD without HQPlayer under $3k.

Discussion in 'Advice Threads' started by Mg248, Jun 8, 2020.

  1. Scott Kramer

    Scott Kramer Friend

    Friend
    Joined:
    May 3, 2016
    Likes Received:
    1,314
    Trophy Points:
    93
    upload_2020-6-8_21-53-44.png

    Screen Shot 2020-06-20 at 3.01.59 AM.jpg

    @purr1n: Caught something interesting (maybe) on this... looks like it's converting to PCM (or quasi editable dsd/ds) internally to apply volume, and possibly the PCM filters. Just like the studios, to edit anything DSD (even volume) you have to convert to PCM* and back to DSD, defeating a lot of the whole point.

    Look what happens if you don't dick with the volume... the volume bypass bit.

    (vol 100%) it bypasses all processing and sends it thru the SCF's only -- low pass filters. Almost like it's properly... getting out of its own way haha!.

    (not defending DSD or anything, do want to play with it sometime, have some files and a pi DOP to DSD extractor I should try out sometime.)

    Edit: AKM4493 tangent unrelated to OP
     
    • Like / Agree Like / Agree x 1
    • List
    Last edited: Jul 9, 2020
  2. Joe Bloggs

    Joe Bloggs Acquaintance

    Joined:
    Jan 14, 2017
    Likes Received:
    42
    Trophy Points:
    18
    Location:
    Hong Kong
    Well,
    1. Most DACs only speak one language in terms of no. of bits. So you could say that any delta-sigma DAC converts PCM to DSD before analog conversion.
    2. On the other hand, there are almost no single-bit D-S DACs in existence anymore. Reason for this is condensed in this paper: https://timbreluces.com/assets/sacd.pdf
    3. Currently, delta-sigma DACs run at sample rates multiples higher than even the highest DSD, and with extra bits (which are unused by incoming DSD data). To the extent that PCM is being oversampled an incredible number of times and decreased in bit depth, all of today's delta-sigma DACs are performing 'DSD-fication' of PCM to one level or another. yes, Including in the 4x DSD1793 in the Pro iDSD (or for that matter, all the DSD1793-based iFi products) the OP originally asked about!
     
    • Like / Agree Like / Agree x 2
    • List
    Last edited: Jul 9, 2020
  3. purr1n

    purr1n Finding his inner redneck

    Staff Member Friend BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    72,576
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    I missed the bypass on the diagram. Indeed a LPF is all that is needed to reconstruct bitstream to analog. (For the layperson, think of this like applying a grayscale downscale of a super high duper resolution 1-bit photo.) You should try this out sometime if you can extract a DSD stream. Just be cautious with stuff from 30k-70kHz where the noise is deposited.
     
    • Like / Agree Like / Agree x 1
    • List

Share This Page