I wouldn't stretch audio either. However, resampling it because the recording device had the wrong sample rate is a valid option. Sony's resampling algorithm is extremely good and preserves quality very well with almost no artifacts.

And yes, you *should be* changing the pitch. Thinking that fixing this sort of thing by stretching without changing pitch is wrong. If the recording speed was off, then the pitch was changed. It should be changed back.

A couple of comments more relevant to this situation:

This was a choral performance. What I found was - not surprisingly - that the audio recording (taken from one performance) was not identical to the video (taken from another). In spite of their best efforts, no-one can precisely reproduce a performance in that detail.
I was not completely satisfied with the result, and tried it again. The first time I was trying to essentially lip-synch; difficult at best. What I later realized was that I had both audio sources - from the camera and the mp3 recorder. So I set Vegas up to feed one into my left ear, and the other into my right. I just had to manipulate things so that I got identical audio in both sides simultaneously, then later mute the camera audio.
What was happening was that pauses between phrases were not identical, and there was one longish segment when the choir (video) "lost the plot" - they actually reached the end of a 52-second segment one whole second late!! Nobody would ever notice unless they were trying to sync audio!!
The phrase gaps I fixed by cutting the audio track in the quiet spots, and moving the track onwards fractionally. The long segment gave me no option - the singers (video) were simply singing slower than the audio. The only way to make that work was to stretch the audio track by one second - it worked perfectly, and my ears can't tell the difference.
So in my vast experience of one case (!!!) I think that stretching audio can work very well. Especially if the degree of stretch is not great.

I am now satisfied with the result; I can't see any flaws with it. Hope you enjoy it wbtczn; the new file is on its way up. Dropbox link to follow.

Dropbox link is https://www.dropbox.com/s/3yyghpgsvra059o/I%20Will%20Rise.ts

>> And yes, you *should be* changing the pitch. Thinking that fixing this sort of thing by stretching without changing pitch is wrong. If the recording speed was off, then the pitch was changed. It should be changed back.

I wholly disagree.

You have no cause to know it is truly the audio recorder--and not the video recorder. Nor, can you know at what speed the final playback device will play. It is a futile ghost chase to change pitch simply to match a different device that may be no more accurate.

I don't care how good Sony's re-sampling is, re-sampling is a bad thing for audio (or video) and causes interpolation and artifact.

Now, I know that no one cares about audio quality anymore---these "modern" days of junk MP3 recordings on Apple iPods are truly disappointing. I never would have thought I would be listening to lower quality recordings 30 years after the 1980s! What happened to the promises of 96/24 and 192/24?

If at all possible, leave your audio (and video) unadulterated. Drop or add video frames instead. An audiophile thanks you.

Kelly, you missed something twelve posts up. This was "not" the result of "the recording speed was off". It was the result of trying to marry the audio and video from two different performances. A little like trying to stuff the toothpaste back into the tube.

"An audiophile thanks you."


1) The original recording was encoded to mp3, no doubt at some low bitrate.
2) The original recording's sample rate was 44.1KHz, it will be resampled anyway.
3) Pitch shifting is much more complex than simple resampling.
4) Any movie broadcast in Region50 is pitch shifted 4%. Back in the early days it wasn't but the people with perfect pitch hated it.
5) Duplicating or droping frames is visually very distracting, I can think of no better way to ruin a video to the extent that no one will be listening anyway.
6) If you're a true audophile why are you using Vegas ?

Bob.

You drop frames at edit points. Completely unnoticeable.

All the other points you make are good cause for fights elsewhere, not excuses for doing further damage.

Maybe some (many?) of you guys have better ears than mine, but to me Elastique sounds pretty darn clean as long as the stretch/shrink is a small percentage.

There are folks who claim they can "hear" the difference between a 96 and 192 sample rate. Good luck with that. I have a friend who runs his speaker wires from amp to speakers on 4" glass insulator standoffs so the wires don't touch the floor or take any sharp bends. And those wires are the size of your finger. I just shake my head and smile, but to him, it's a religion.

So as for pristine audio, I'd suggest the good ol' A/B test to see if it really makes much of a difference. For my choral stuff, I can't tell the difference. But then I don't mind mp3's for casual listening, either.

musicvid, yep, i got that. I was replying directly to a few posts from folks saying that the pitch shouldn't be shifted when doing a speed change. Of course, that doesn't apply to the original situation as we now know. But, in cases where the audio does come from the same performance, my comments do apply.

Kelly, If you or another poster would like to start a new thread with that subject, I'll be pleased to have that discussion with you. Been there. I find it impossible to follow two comingled discussions, although I'm sure that wasn't your intent or sole doing.

Thanks all for your input and insights. I've learn most of what I know in Vegas and Sound Forge by trial and error...and error....and error. I don't do these projects often enough to really learn all the tools of the trade.

The doing the video was a spur of the moment thing for me. As I said earlier in the thread, my wife is the director. Also, my son is the third soloist....so I decided at the last minute to grab my camera as I headed to the church. I knew I had a lot of herky jerky movements in there when I zoomed in and out. I figured I would do some video cuts at those points.

Ron - I especially appreciate the time you put in to 2 cuts of the video to show me what is possible. I would have loved watching while you were doing the editing!

@wbtczn " I've learn most of what I know in Vegas and Sound Forge by trial and error...and error....and error."

Heh - you just described my life! :) That's where many of us are - in fact I think the description of an expert is the bloke who has made more mistakes than anyone else!

And thank you for the opportunity to tinker and learn some new stuff!

Cheers

Ron