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Problems Creating an Isolated Score Track

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Hi all.

I don't often post in this particular forum, but I am in need of some assistance. I am trying to work on an isolated score track for the "Ghostbusters: We're Ready to Believe You" project. I've run into the problem of the tracks not synching properly. Now, I've lined up 3 or 4 tracks perfectly for their starting point, however, they progressively fall out of sync. I've reasoned that this is because the DVD audio track that I am using as a base is from the PAL DVD.

Am I right in that the way to get around this would be to time-stretch the DVD audio to the equivalent 24fps runtime? Since that is the film standard, and the PAL DVD is sped up by around 4% (it's not time-compressed). Then, using that stretched audio as a base, sync the tracks of the score and then when I'm done stretch the completed track to the 25fps runtime? This would cause pitch problems and audio artifacts wouldn't it? Is there a way to do this without sacrificing audio quality?

I know most of you deal in NTSC, but the project is going to be PAL. I am capable of synching the tracks to the audio - but there's no point doing that unless I'm doing it correctly. I would really appreciate any feedback. Are the people who created the isolated score tracks for the IsoMix and Editdroid discs around? I know they were working with an NTSC disc - but did that involve speeding up and/or slowing down audio?

Thanks in advance.

To contact me outside the forum, for trades and such my email address is my OT.com username @gmail.com

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NTSC is slightly slower than the actual film, but music tracks wouldn't generally be long enough for you to notice desynchronisation.

As for you, I think it makes a lot more sense to just speed up the music tracks and then sync that to the unmodified DVD. No sense slowing down the DVD, then speeding up both the DVD and isolated track at the end of the process when you only need to make one change. You'll experience less of a quality drop speeding up the audio than slowing it down. Just make sure that when you speed it up you preserve the pitch.

The only reason I'd suggest doing it the way you posted was if you were going to release an NTSC copy, but if that were the case I'd recommend you just get an NTSC copy of the film, do all your work, then speed the isolated track for resynchronisation with your PAL copy.

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Thank you Gillean. That makes a lot more sense than my idea.

So, now the question is: what is the exact % I need to speed up the audio by (I'd read that it was not 4% but something like 3.987% or something like that)?

And how should I go about doing it (ie. which method/program will allow me to do it while preserving the pitch and retaining quality)?

I am using Audition for this, and while I'm familiar with Photoshop and Premiere, I haven't really experimented with Audition before.

To contact me outside the forum, for trades and such my email address is my OT.com username @gmail.com

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To get from NTSC to PAL speed, you need to reduce the running time by 4.096% (actually something like 4.095904...

Most audio programs these days should be able to do a simple speed up (resample) with good quality. This will affect the pitch, however if your main audio track has been produced the same way then it will match.

Pitch correction is only used in DVD production at the director's request, because it can add digital stepping. Serato Pitch 'n Time is supposed to be very good for pitch correction - unfortunately it only runs on ProTools, which requires special hardware.

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