Recording problem (Audacity seems to break)

[mimayin]

Hi,

I've been trying to use Audacity to record an 8-hour set at a nightclub, but I've tried twice now and in both cases its apparently broken.

At the end of the set, I saved the Audacity project to disk but the .au files in the saved project are dated only up to two hours before the set finishes, so it seems like it only managed to record the first six hours. Even worse than that, if I open the Audacity project and export it as a WAV file, it only gives me the first hour and a half!

I really need to get this recording out of Audacity into a format I can use but it's proving very tricky. The .au files are recorded in 96Khz 32bit stereo.

I've tried splicing all the .au files together (there are 16834 in total) but the resulting .au file is then unreadable, presumably because all the individual files have headers.

I've tried adding all the .au files into a winamp playlist with winamp configured to write the sound out to wav files, but the wav files are then distorted/play really slowly etc...

This is doing my head in, why does Audacity break like this when you try to record 8 hours of sound? Did I do something wrong? If I can't get this recording out of Audacity it's going to be quite a disaster.

Next time I think I'll try using Audition to record the set, as audacity seems to craete thousands of tiny files which probably doesn't help..

[steve]

The ".au" files are NOT audio files - they are audacity data files. If you mess with these files, your project will break.

Make sure that you have plenty of free hard drive space - if recording at 16 bit 44.1 kHz, you need an absolute minimum of 15GB + 10% of your hard disk, free space (for a 120GB hard drive, that is 25 GB - at 96 kHz it would be more like 60 GB). This is an absolute minimum, and any editing at all will require additional space.

Try recording some shorter sessions first so that you are familiar with Audacity before trying a big recording like this.
You will probably find these tutorials very helpful: http://audacityteam.org/wiki/index.php?title=Tutorials

[MDOC]

I suggest exporting as an mp3 file rather than a WAV file. Considerably smaller HD space will be required.

[steve]

I suggest exporting as an mp3 file rather than a WAV file. Considerably smaller HD space will be required.

but lower sound quality.
WAV files are useful because if you need to do more editing you still have a pristine audio file to work with rather than one that has been slightly mangled by mp3 compression.

[MDOC]

I suggest exporting as an mp3 file rather than a WAV file. Considerably smaller HD space will be required.

but lower sound quality.
WAV files are useful because if you need to do more editing you still have a pristine audio file to work with rather than one that has been slightly mangled by mp3 compression.

True, but with floating 32bit sampling, it's not really a problem.

[steve]

True, but with floating 32bit sampling, it's not really a problem.

You don't get floating 32 bit samples with MP3 files - 32 bit audio gets down-sampled to 16 bit as part of the compression encoding.

[MDOC]

Hm, I forgot that the 16 bits is part of the mp3 protocol standard. Thanks.