"Did you track a whole track into SF?" - The whole EVENT?

"Did you open a Copy in SF and get it back as a take?" Yes.

"If the latter it should be very easy to check if anything has slipped." Well, maybe. Yes it is easy to check, I'm wanting reassurance that adjusting/cleaning the audio doesn't change its length and thence its sync with the audio.

Using the "T" for cycling the take I use as a matter of course just to see if there is a natural/better audio/video experience. I'm just wanting to get a for certain error-removal from my work flow. Hmmm...

I think you've hit the logical wall of trying to prove a negative being impossible.

You could drag the take down to another track and compare the wavforms at the beginning and end, that'd be the easiest way to ensure nothing has slipped.

Bob.

"I think you've hit the logical wall of trying to prove a negative being impossible." Ah, yes . .

However, if it was or wasn't out of synch would the audio "pink" warning still be effective? If it DOESN'T go pink then it could be out of synch and I wouldn't know?

Well thinking about this some more, what two criteria does the audio have to meet to stay in sync.

1) Start at the same place on the T/L.
2) Contain the same number of samples at the same sample rate.

Neither of those seem too hard to achieve.

However if you managed to change something in SF that would by design cause the sync to go off, like trimming half a second off the front then Vegas has no way of knowing I'd think. Hopefully though you'd be hard pressed to do that by mistake.

As to the going pink thing. Well once it's back in Vegas it should work as per usual although I've had some oddball results from the out of sync indicator. Like delete the video and it tells me I'm 23 hours out of sync!

One could do a fairly simple test, do something in SF that will throw the sync off and see what happens.

Ah but maybe I see what's in the back of your head. No I don't think Vegas is continuosly checking sync like you could / would if the audio had embedded time code. I think ALL it has to work on is the start time.

Bob.

Bob.

About a year ago I shot a presentation that lasted for 45 minutes. I was unable to connect to the sound system because there wasn't one, so I was forced to use an onboard mic. To add insult to injury I was "placed" by the client directly beneath an industrial air conditioning vent. What a racket that made!

Knowing what I was going to get, before the presentation began I recorded 10 seconds of "room tone" without anyone present. Then I recorded, nonstop, the 45-minute presentation with the AC droning overhead (not to mention I was getting cold with the AC blowing directly on me).

Got back to the editing room and ran the sample through Noise Reduction and it worked like a charm. There was no audio slippage whatsoever.

i've used Sony's NR in Vegas as a track FX & had no slippage. But you're doing it in SF, right? Maybe you should make a copy of the non-NR track right below then run it via Vegas track FX.

but fars is right: put it under/above a non-modified copy & see if it' different.

why do you ask, does is sound off?

Sorry, I missed the original Sound Forge reference... my bad!

I was using NR in Vegas, like the good Friar mentioned.

Happy "why do you ask, does is sound off?" . . .well . . . not in the majority of my work. No.

It is only under certain circumstances. It is when I PTT and then have it run through a projector via a mass of cabling. I'm just wondering that if there IS a potential "softness" and it is around my NR or "other" SF work then I need to keep a weather eye out for this.

I'm real sorry to sound so vague - not like me I know!! But I was just pondering the options of what happens within SF that might/could be carried over to Vegas, that when the then projected video and the audio is split away to a separate desk - could slippage be more noticeable? As an acid test I have run tape to my own short range, 1 metre cabling away monitor it is hard as nails!!

This is an information-seeking question (hopefully I'll learn someting!), not a criticizing one...

Why do you post your video's in Sound Forge instead of Vegas?

Oh, not a prob Jay.

When I right click I get an option to open Copy In Sound Forge. Do you mean, why go there anyway? Well, there is more control and finesse with the waveforms - I guess? That's what I thought? Plus I get to play with all the other options and I can repeat the last action, I can get to more faster and undo faster - yeah? Dunno, SF is less lumpy. It feels more comfortable and more intuitive.

SF is less lumpy. It feels more comfortable and more intuitive.

Then that's all that matters!

Thanks for the explanation.

PLUS, it is away from Vegas. Sometimes when I'm "curing" a section I don't want messing with Vegas.

Just a quick heads up. I know you are talking about the Sony Noise Reduction plug-in but it should be noted that not all plug-ins are created equal. I have BIAS Sound Soap 2 and the DirectX plug-in has a NASTY bug of shifting the audio out of sync! It actually rolls the audio to the right and loops it so that they very last thing in the clip is now at the beginning!!! (if you have silence at the beginning and end this will not be as obvious) This makes everything out of sync when it gets back into Vegas.

The solution is to NOT use the DirectX version of BIAS Sound Soap but to use the VST plug-in instead which doesn’t seem to have this problem. I’m sure this is due to the delay required to process the audio not being compensated for. There may be other plug-ins with this problem so it is definitely possible to get out of sync by processing with SF depending on the plug-ins you use.

You are safe with Sony Noise Reduction but stay away from BIAS Sound Soap 2 DirectX version and use the VST version instead.

~jr

well, are you sure the audio sync "problem" isn't due to the way the aud is setup? Since the sound takes longer to get to your ears then the light to your eyes, if all the speakers are in the front & you're in the back running the projector, it could be off slight... to you. :)

Johnny thanks. It has been my Belt n Braces attitude to all things IT ( most of it IS a mystery! )that came into play when I asked the original Q.

Could/Would/Can doing something to an event's audio work its way back thru - no matter how slight - and be made apparent by a time delay on the projection<>audio. I have to say that the majority of the projection was fine. It is now thinking back that maybe over - and just over - the parts I had done some audio hospitalization, that I was sensitive to very slight softsync.

HappyFriar? Nah, I sat all the way thru from exactly the same place.

I could think of nothing you could do that'd cause a variable slip in sync during playback. By that I mean it seem in sync say played in setup A and out of sync in setup B.
The most logical thing to blame is setup B.

And as noted sound travels relatively slowly, that's why large venues have those delay lines.
I'd also add just from my own experience that sync is quite hard to judge, opera is a nightmare. I've come accross people who speak out of sync too. We tried to 'fix' one such person as several of us were convinced somehow things had gotten out of sync. Later we found out that was how he talks, opens his mouth, lips move for a few frames and then the words come out.

Bob.