Error while recording and exporting 7,5 hours live music

Hello everybody,
last friday we had a vinyl only party, 3 djs played one after another for 7,5 hours non-stop. rare vinyl discs and great music…
I recorded all this sound with audacity 2.0.2 and windows7.
then as usual i made - export - wave.
CPU exported the track for 20-30 minutes. So i got 4,5 gb wave-file. Good. But when i played it - there was only 30 minutes cut and absolutely nothing else. with 4,5 gb!

This record is very important for me. So the question: is there any opportunity to recover my 7,5 hours record?

thanks in advance.

I think we know what happened.

4 GB
The WAV format is limited to files that are less than 4 GB, because of its use of a 32-bit unsigned integer to record the file size header (some programs limit the file size to 2 GB).

I think there’s a trick to retrieving sound files that go over. We need to wait for a senior elf.


the problem is solved, just imported RAW file back to audacity!

sorry for bothering!


[ EDIT ] - Too late!

Try importing as Raw Data.

You’ll need to know the bit depth/encoding (16-bits?) and and the sample rate.

If you get pure noise, the bit depth or offset could be wrong. (With 16-bit files, an offset of 0 or 1 should work and with 24-bit files, try 0, 1, or 2.)

If you ‘guess’ the wrong sample rate, the speed will be off.

Once you get the whole file export to FLAC (or some other compressed format).

You’ll get a little glitch at the beginning where the WAV header is converted to audio and you can edit that out.

Next time, save your Audacity project AND export to FLAC. …And, whenever recording anything critical where there’s no chance for “take two”, set-up a 2nd back-up recorder and record to both. :wink:

Computers are the least reliable things we own, and it’s easy to make a setup/configuration error… Things can go wrong and sometimes you don’t realize there’s a problem 'till you get home and then it’s too late!


There is a 32-bit file-size field in the WAV file header and that limits the reported file-size. Depending on how the software writes over-size files, that 32-bit value may “roll over”, throwing-away the most significant bit(s) and you get what looks-like a random file size.

whenever recording anything critical where there’s no chance for “take two”, set-up a 2nd back-up recorder and record to both.

What he said.

This recording session looks insanely complicated, but (past bad lighting) it’s just me and Audacity recording a performance on the left and the performer’s own recorder (on the right) with the duplicate backup.

The client was happy with my sound files, so we didn’t need the backup.

I think I still have that session around here somewhere.