I have an .wav file recorded using Studio One on a Macbook Pro (running Mojave).
Studio One shows the file as being ~1h8m45s. When I export it, iTunes and Finder both agree at that length.
But when I load it into Audacity, the audio is ~1h1m11s long (the last sample is at 01:01:10:27431). I saw this happen in v2.1.1, and again with my update to v2.3.3.
I then have to “change tempo” to get the audio back to 1h8m45s.
Everything (Studio One, FInder, iTunes, Audacity) agrees that the audio is 44.1K, so it’s not that.
Please post the full information about the file from: https://mediaarea.net/MediaInfoOnline
You may be far better off with Change Speed rather than Change Tempo. Change Speed just drags its finger on the record a little but leaves everything else alone. Both Change Pitch and Change Tempo have to rip the sound to pieces and try to smash it back together again. They have much higher chance of error.
I’m doing the math in my head, (and it hurts!) an error that small can be the difference between NTSC (Analog US video) frame rates and natural rates. 29.97 instead of 30. Does any of that ring any bells?
In film land, that’s a video frame off every minute. I need to whip out my slide rule.
Nope. The error is too big for that.
The error is 1.12367, not 1.001.
And they’re both at 44100 sampling rate…
Yeah. I want to see the file analysis, too.
Here’s something you can try while we wrestle with this.
Make a half-hour recording in Studio One. Length not critical. Open it in Audacity. Reduce everything down to seconds. Divide. Is the error still 1.12367?
Thanks for all of your information. I’ll make another recording today.
Here is the output from MediaInfoOnline:
Complete name : later audio.wav
Format : Wave
File size : 520 MiB
Duration : 1 h 8 min
Overall bit rate mode : Constant
Overall bit rate : 1 058 kb/s
Encoded date : 2020-03-01 19-14-4
Format : PCM
Format settings : Little / Signed
Codec ID : 1
Duration : 1 h 8 min
Bit rate mode : Constant
Bit rate : 1 058 kb/s
Channel(s) : 1 channel
Sampling rate : 44.1 kHz
Bit depth : 24 bits
Stream size : 520 MiB (100%)
Strange!!! I can’t even comprehend how this is possible! There are 44,100 samples per second so the playing time is just straightforward math.
When you actually record & play-back there is physical clock and no clock is perfect, but the “math” should be perfect.
I can imagine some kind of corruption where the number of samples is wrong (in the file header) but I expect that to show-up at the end of the file, not as an overall tempo-speed problem.
There’s probably something screwy with your WAV file but I don’t know what and MediaInfo doesn’t give any clues.
What is the recording? Music? Speech?
Are you sure that it is playing at the wrong speed, and not just ending too soon in Audacity? (truncated)