• Apple Final Cut Pro Legacy

  Audio Sync Problem – Sampling Issue?

  Posted by Steve Ewing on January 12, 2010 at 7:21 am

  Hello,

  I recorded a live event (speaker’s panel) where the audio was recorded directly out of the PA system, completely separate from the video track.

  When I brought the video file and the audio WAV together in FCP6, they don’t exactly sync. In fact, the audio is slightly longer than the video track. For example, if I sync them up at the beginning of the video, by an hour in, the audio is more than 10 seconds behind the lips in the video.

  My theory is it has to do with a sampling problem. Unfortunately, we made a mistake and sampled the audio at 44.1k and the video at 48k.

  Short of changing the speed of the audio track in FCP to 100.5% or something, is there a solution? For example, is there a program that will change the sampling of the audio track from 44.1 to 48k?

  What is it, and where can I get it?

  Thanks,
  Steve

  Bouke Vahl replied 16 years, 8 months ago 2 Members · 1 Reply
• 1 Reply

• 

  Bouke Vahl

  January 12, 2010 at 11:03 am

  Steve,
  Your therory is wrong. Sample rate could be anything without affecting the duration.
  (Although by changing the sample rate a tiny bit you can change duration…)

  How was it recorded and ingested? Perhaps the recorder drifts a bit over time on playback.

  You can change sample rate in any audio package. You even can open the audio in QT pro and export to 48 Khz.

  Easiest way of getting rid of the sync problem is cutting out small pieces here and there. (assuming you have to cut anyways)
  If you can’t cut, you can change the duration of the audio in an audio editor. Do use ‘pitch shift’ (or whatever it’s called in the package you use) if you can. This will be fast, unnoticable for the audience and leaves you with the highest quality.

  Bouke

  https://www.videotoolshed.com/
  smart tools for video pro’s

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