AIF vs WAV render proxy gray line

[Nick Meyers]

the green line on top of the audio clip indicates that there is some sort of miss-match somewhere.

the grey line indicates the same thing, but that that file has now been rendered.

if you want, you can check the clip’s properties by right clicking on them ,and choosing “properties > format”
there must be some slight mis-match?

that it flips from sequence to sequence is interesting, but hard to sayt what;ls realy goijg on there without knowing the seqnce settings in detail (audio part of them, anyway)

“My sound designer feels that FCP is somehow changing one of the other a small small amount during the OMF export.”

well, the OMF export will be converting all the files to a uniform setting:
whatever you chose when you made the OMF.

i did a whole feature where every file had a slightly off-standard audio rate
(this was a 24@25 PAL project, where Cinema Tools alters the play-back rate of the files,, altering the sample rate in the process)

the sound editors compared my OMF audio with a few takes re-captured from DAT,
and said they could hear no difference

” the reason this is a big issue for my project is that it is animation and the animators animated to exports straight out of FCP”

not that big a deal.
based n my experiences, your timing wont change at all.
nevertheless, you should always put pips at the head and tail of your exports so sync can be verified.

nick

[Tippytink]

Thank you for your response.

I did check the properties and the only difference is that one is a wave file and the other is a aif. They are both 48, 16bit, mono audio files. I agree that the change is not a big deal. The sound deisgner and I are both just very curious on why things like this happen. In FCP with your timeline settings you have only the choice of bit rate, sample rate, and if it is stereo or mono. So it is indeed very strange on why the render line would switch from one file type to the other when copied into a new timeline with the same audio settings. (maybe there is a deaper timeline setting I am unaware of) Also, when you make OMF’s you only have the choice of bit rate, sample rate, and if it is stereo or mono. I am not an audio person, but I am thinking that maybe there is a slight difference in wave files and aif files themselves (which makes sense) to where FCP has to change one or the other to match in the timeline. (within FCP 5) Still confused though.

Melissa

[Nick Meyers]

“The sound deisgner and I are both just very curious on why things like this happen”

me too!
i’ve had clips where there seems no reason they should have the green line,m and they do.
i think it;s a format thing like you say,
but i have no idea how you;d control it, or create the situation you have.
like you say, have a deeper look into hte sequnce audio settings.

“Also, when you make OMF’s you only have the choice of bit rate, sample rate, and if it is stereo or mono”

ok, here’s my half-educated guess:
AIFF and WAV are just slightly different “wrappers” for audio that basically uses the same type of compression
(kinda guessing this..)

when you open an OMF in ProTools, you have to tell it what format you want, AIFF, wav, or whatever.
(this i know)

what happens when you make an OMF is all the audio gets packaged into one file, along with a “set of instructions” on how it all un-packs
so my guess is that the OMF is behaving as another sort or “wrapper” for all that audio.

cheers,
nick