Can't Seem to Save Long Audio

I have converted a long audio book which is over 25 hours to WAV in another program. I am left with 4 wav files which are approximately 6 hours long each. I would like to combine them together and export them as an AIFF file. When I try to do this in Audacity, it acts like it saved the file correctly. The resulting file also imports into iTunes and appears to be the correct length. However, if I try to convert it in iTunes to another format, it stops at around 5 hours. If I open the AIFF in Audacity, it only displays about 5 hours of the audio and acts like the rest isn’t there. I have tried v2.0.3, v2.0.5 and v2.0.6 nightly build but they all behave the same. I got these versions via the .zip type of download. I am using OS X 10.8.3.

Any ideas?

Some formats have natural limits. Some are imposted by the sound program.


Sometimes viewing the problem too closely isn’t good. What’s the goal? I don’t mean the one in your post, I mean “I want to do this because…”


The high level objective is to losslessly strip DRM from an audio book so I can convert it to other formats and use it on any device I want. I wanted to end up with an Apple Lossless file because iTunes would play that. This is not an easy thing to do. “They” make it plenty difficult. However, I was able to get it into 4 wav files losslessly via a method I don’t wish to document here. I just needed to get those WAV files combined somehow and converted to Apple Lossless.

I am unsure what limitations AIFF has. I know WAV has some pretty serious limitations as documented here:

I eventually got around the problem by exporting to FLAC and then using XLD to convert the FLAC to Apple Lossless. I guess large AIFF files just won’t work.

AIFF and WAV are close cousins. AIFF has reverse byte order (big-endian…something) and provision for additional file information, but past that they’re pretty similar. So I’m not shocked they both fail.

The classic way to get around copy protection is burn the show to a CD and then rip the CD. You can also record the show live with SoundFlower.

I would pick a format that “looks” like several songs in succession rather than fighting the “surveillance sound file” problem.


Thanks. Yeah, I’m just stubborn like that. I wanted to end up with a single file. :slight_smile:

You sound like a fellow developer. I am interested in learning more about the file header structure of different sound file formats. Can you point me to a good resource by any chance?


Though a WAV file can contain compressed audio, the most common WAV audio format is uncompressed audio in the linear pulse code modulation (LPCM) format.


AIFF has the same 4 GB maximum file size limitation as WAV.

Audacity can export to 16-bit Apple Lossless but you have to add FFmpeg to your computer, then export using (external program). Click the Options… button, enter the following command

ffmpeg -i - -acodec alac "%f"

then add the “.m4a” extension (without quotes) to the end of the exported file name.


Thanks Gale! That was a very helpful response.

I had better add that after the upcoming Audacity 2.0.6 is released, the “recommended” installer of FFmpeg will be updated to FFmpeg 2.2.2, but an “ffmpeg” binary that Audacity’s command-line exporter can use won’t be included for Mac.

It’s easy to find an “ffmpeg” binary for Mac by searching online, but the path to ffmpeg would have to be included in your export command for ALAC, such as

"/Applications/FFmpeg/ffmpeg" -i - -acodec alac "%f"