• Apple Final Cut Pro Legacy

  How to layoff an LTRT mix

  Posted by Chris Sanderson on March 9, 2009 at 1:00 am

  Hi everyone. I’ve just received an LTRT mix that is to be used for all of our deliverables. I’ve never laid off an LTRT mix and Im just wondering if there is anything special I have to do to ensure it is capable of being decoded to 5.1 when played back. It comes into Final Cut as a stereo track and I just want to make sure im not missing something.

  Thanks in advance.
  Chris

  Nathan Chitayat replied 17 years, 2 months ago 5 Members · 5 Replies
• 5 Replies

• 

  Mark Raudonis

  March 9, 2009 at 2:15 am

  LT/RT should work just like a straight audio file. We’ve done nothing special with it whenever
  we do this.

  However, a Dolby E mix is an entirely different animal. You really should consult an expert if you’re dealing with that.

  Mark

  PS. I hope I’m right, ’cause that’s what we’ve been doing! Someone can correct me if not.
• 

  Michael Gissing

  March 9, 2009 at 8:38 am

  Lt/Rt is simply the way a stereo file is called when it is designed for decode by a Dolby Surround decoder (sometimes called Dolby Pro Logic). This doesn’t decode to 5.1 but left, center, right and surround (mono).

  You must make sure the left channel is panned hard left and the right panned hard right. Leave the level at unity (no added gain).
• 

  Chris Sanderson

  March 9, 2009 at 1:07 pm

  Thanks guys. Shouldn’t the track already be panned hard left and hard right when I get it from the mixers or is this something I need to set up in Final Cut?

  Chris
• 

  Ryan Scott fitzgibbon

  March 9, 2009 at 3:05 pm

  Hi Chris,

  I work with LT/RT Mixes almost daily in FCP. Hopefully I can Help you out.
  the file will appear as stereo. as you mentioned the the file should be hard panned already.

  1 make sure that your track is set to stereo pair.
  modify menu>stereo pair

  2 audio outputs should be set to stereo pair.
  this is important. if set to mono outputs the lt/rt mix will decode properly off the FCP timeline,

  however upon playback the file created will collapse to centre channel.

  in regards matrix decoding, the original format of Dolby pro Logic only decoded a mono track for both surrounds, in the greatly improved Pro Logic II format of matrix encoding/decoding each surround speaker has seperate information. the end viewers home theatre system equiped with PLII will derive an LFE track for your sub . giving a 5.1 listening exoerience.
  Granted this is not as discrete an experience as Dolby Digital 5.1 (ac3 file)
  Dolby Pro Logic II is considered an acceptable delivery format of 5.1 surrpund sound by industry professionals and broadcast houses alike.

  CHeers

  Ryan.

  Ryan
• 

  Nathan Chitayat

  May 21, 2009 at 7:54 pm

  What is meant by “audio outputs should be set to stereo pair” and how do I do this? Also when I pan my RT all the way to 1 and my LT all the way to -1 and then stereo pair them, the resulting file says “-1” when I double-click on it… am I doing this right?

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