I’m using audacity to record voice and a Vixia camcorder to record me, the issue is that when I put the files into an NLE, specifically Vegas, the Audacity .wav will gradually desync from the camcorder audio, I’m asking here to rule out something I don’t understand like NTSC, because when I use change speed of 0.99970 it’s approximately correct.
Any help appreciated
NTSC isn’t that hard. It turned out at the dawn of color (not colour), the technique most gentle and agreeable to people left watching in black and white involved pushing the frame rate off a little (this is the very highly sanitized version). NTSC television framerate is not 30. It’s 29.97.
And yes, it causes no end of problems. A 60 minute show is not an hour long, etc.
Let’s see if I remember this… Put down 3 carry the 7… times 13…
It intentionally never comes out even, but that’s the accurate-ish framerate. The conversion is that over 30 or 30 over that.
29.97002997
If you have processing software that doesn’t “know” about NTSC, or you in any way cross them, you will get a fairly standard time offset.
That’s different from recording on two cheap digital recorders. If they’re not both on 44100.000 Hz sample rate (for example), you get to eat the difference with Effect > Change Speed. That number could be anything. The up side is unless you got super cheap microphones, the offset will probably stay constant show after show.
Koz
Flash from the past. That also works out to 1000/1001. And that’s not to say you can’t have two errors, but that’s the one I’m familiar with.
Koz
Oh, gosh, that’s troubling, uhm, I mean they’re both 48hz, Audacity, and the Canon Vixia HF R600 camcorder, the mic is, I dunno? The Samson Go Mic https://www.amazon.com/Samson-Mic-Portable-Condenser-Microphone/dp/B001R76D42 seen here, it doesn’t seem crappy but if you mean something expensive and high end comparatively yeah it would be cheap. They’re both set to the same sample rate, so is it the microphone? Or is there more to handling the difference than change speed?
I am not clear if you have checked the Samson’s sample rate or not, but if not you can do it on the Recording tab of Windows Sound.
The current Audacity version is 2.1.3 from http://www.audacityteam.org/download/windows.
Gale
Well don’t I feel foolish, I’ll do another long recording tonight and report back.
Nope that wasn’t the issue, it seems to be a consistent offset, so what I sit in Audacity with both tracks and change speed until they align? Then that’s probably good for every edit?
It had to be tried but when you said Change Speed of 0.99970 approximately fixed it, that suggested it was an NTSC issue.
It’s best to use the New Length control in Change Speed with the Selection Format set to samples (click the downwards pointing arrow to right of the time digits). Then as long as you are using Audacity 2.1.3 you will be able to make the Audacity WAV exactly the length of the camcorder audio.
If necessary, install FFmpeg which should let you drag the camcorder video file into Audacity which should then let Audacity import the camcorder audio.
Gale