Converting 5.1 AC3 to 2.0 Wave

Discussion in 'Audio' started by BigOlly, Mar 29, 2009.

  1. BigOlly

    BigOlly Member

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    Hey everyone,

    Just playing around with some video editing. I've been converting 5.1 AC3 audio to 2.0 wave because it's easier to work with.

    However when I convert the AC3 file to wave it's much too quiet. If I check the normalize function (100%) it's better however my sources all come out at a different volume level.

    I'm using DVD decrypter to demux the AC3 then I'm converting to wave with headac3he.

    Any advice would be greatly appreciated.
     
  2. davexnet

    davexnet Active member

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    I know the Besweet interface has an option to compress the dynamic
    range, but not sure how effective it is.
    Open the WAV in an audio editor. If you see a situation where there
    are a few peaks but most of the file has much lower DB values,
    it needs to be "compressed"

    Compression on an audio file generally reduces the peaks,
    and increases the parts where the DB was low, so that the file has
    values that are closer together. Then you can normalize it,
    to increase the overall volume. This is very basic audio editing.
    Try the free audio editor Audacity.
    Hope this helps.
     
  3. olyteddy

    olyteddy Regular member

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    You could also give AVIDeMux a shot. It reads AC3 and has a bunch of filters for levelling and such.
     
  4. BigOlly

    BigOlly Member

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    That's some good advice davexnet so thank you for that. I'm quite familiar with audacity but I've never used the compressor effect. Do you have some idea what would be the best settings for compression for audio to be used on a DVD?

    Oh and should I use the normalization effect in audacity (-3db)?

     
  5. davexnet

    davexnet Active member

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    I've done it a few times in the past, tried to use a generic process,
    but there is no substitute for actually looking at the data and seeing
    what needs to be done.
    Some of the files I worked on, the speech and general background
    noises were so low, but there were a few peaks here and there for the
    loud sound effects of the movie, etc. In cases like that,
    you have to reduce the peaks first, because normalize by itself
    wont work.
     
  6. BigOlly

    BigOlly Member

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    Thanks guys. I've got another question but I'll start another thread as it's a bit separate to this topic.
     

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