Export Full Dynamic Range with 24-Bit Samples



  • Still not sure I understand the Full Dynamic Range thing. As a practical example, what would happen if I export my 24-Bit library (.ch1) files and say NO to Support Full Dynamic range?

    I don't have my engineers hat on right now, so I need a basic understanding of what would this do to the sample content when the user extracts? Is there any audible difference?

    Still confused, because when I tried to turn on Full Dynamic Range with 24-Bit Ch1 files, it seem to increase the compression even more than the total size of the samples and I ended up with a ton of .ch1 files. For example, my library is 13GB, but ended up with about 8 2GB split archives, which is way more than the initial 13GB.

    Trying to understand....Thanks in advanced.



  • Bump...

    Would really like help on this one



  • Are the 13GB .ch1 files or uncompressed waves?



  • @Christoph-Hart The .ch1 files are compressed from uncompressed .aif files.



  • Part 1

    Let me be more clear just to make sure I"m explaining it correctly. I have a bunch of .aif sounds in folders which represent a complete library that is 44GB. The library contains a mixture of 16 and 24 bit uncompressed audio files. I encode the library and convert to .ch1 compressed and the total library is about 14GB, which is great.

    For this part, I just want to make sure I'm not loosing any quality of my 24-bit audio files given the dramatic compressions, which is awesome. Mind you most of the files have long decays, which your compression loves, so that may be where all the savings is.


    Part 2

    I go to create the .HR archives and choose 2 GB Split archive size and Yes to Support Full Dynamic Range of the 14 GB files

    I'm ending up with about 10-2GB files, which ended up being 21 GB, which is more than the original 13GB .CH1 total library. So I'm just wondering if this makes sense

    I don't want to loose quality, yet I still want to keep the archives low. So I need to know what I'm loosing or gaining.

    So in Summary:

    • Library Size: 44GB uncompressed AIF files
    • HLAC Compression to .CH1: 14GB
    • Archive with Full Dynamic Range Off - 6.78GB (4-Archives)
    • Archives with Full Dynamic Range On - 21GB (10-Archives)


  • And what's even more weirder is that when I have a mixture of 24-bit and 16-bit files and encode to CH1 I get 14GB as previously stated, but when I convert all of the files to 16-bit and encode, I get 18GB.

    So it seems that the encoder compresses 24-bit better than 16, which is even weirder.



  • OK, so first things first. The Full Dynamics mode is not 100% lossless, but it will practically have no audible artifacts unless you feed it with special test signals. The ch1 files, which use the HLAC codec are always 16 bit, but it will normalise quiet signals to use the full 16bit range at any point.

    The .hr1 files which are used for distributing just use the stock FLAC codec which does not apply these tricks. However I need to use the 24bit format with FLAC (otherwise I'll be chopping away the stuff I am trying to preserve with HLAC Full Dynamics). However this might result in a bigger .hr1 split archive than the HLAC files because 24bit > 16bit, so this:

    I'm ending up with about 10-2GB files, which ended up being 21 GB, which is more than the original 13GB .CH1 total library. So I'm just wondering if this makes sense

    is expected behaviour (I don't care too much about download size, but you could exchange the FLAC codec inside the split archive compressor with HLAC for Full Dynamics).

    Library Size: 44GB uncompressed AIF files
    HLAC Compression to .CH1: 14GB

    Sounds about right.

    Archive with Full Dynamic Range Off - 6.78GB (4-Archives)
    Archives with Full Dynamic Range On - 21GB (10-Archives)

    Also expected. If you disable full dynamics, it will use 16bit FLACs which are way better than HLAC in terms of compression ratio.

    when I have a mixture of 24-bit and 16-bit files and encode to CH1 I get 14GB as previously stated, but when I convert all of the files to 16-bit and encode, I get 18GB.

    Not sure how this happens, but one explanation might be that if you are selecting Normalise Samples but your 16bit files are not normalised, it will compress quantisation noise that is brought up during normalisation, while FullDynamics does not do that.



  • Thanks so much for the detailed explanation and it is much appreciated.


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