Saving a corrupted audio file with Audacity

I recently completed an hour-long phone interview for a Innovative Interactivity article I’m putting together. About a half hour in, the Marantz PMD-660 I was using suddenly stopped recording and I had to quickly put a halt to the questions. Strangely, the recorder was still recording information, but no sound was coming through the headphones (let that be a lesson to anyone who doesn’t monitor their audio). I asked my subject if I could call them back, checked the batteries, restarted the player and pressed record. The recorder seemed to be doing fine.

The second half of the interview went swimmingly, but when I dragged the files off the CF card the first half of the interview would not play in any of the many programs I tried it in. I can’t tell you how far my heart dropped in that moment.

I tried some data recovery software but was continually frustrated by the lack of results. Finally I ran across a suggestion to use Audacity, and holy snikes it worked! Below I’ve detailed the steps I used to save a corrupted audio file from the depths uselessness.

1. Command I – Check the file to see if there’s information. On a Mac that’s as simple as single clicking the file and pressing command I. When I did this I noticed the file had roughly the same amount of information the second half of the interview did, so I figured the data was there.

2. Download Audacity - Next I downloaded and installed the free audio editing software Audacity. Audacity has been around for awhile, and it’s a favorite for its ease of use and surprising flexibility.

3. Import Raw Data – Open Audacity and go to File>Import>Raw Data. Select the corrupted file and press Open. An Import Raw Data dialogue will pop up. I just left all the options as default. Audacity will import the data, and if you see a waveform, you’re probably in luck! From this point I tested the file and was pleased to hear the previously unplayable interview loud and clear.

4. Export – After I determined the file was playable, I went to File>Export and chose AIFF from the drop down list. This allowed me to save the file to my desktop. I will say that somewhere in this process the sound quality was affected (my voice sounds deeper and more warbly than usual) but since I was using the audio for notes, it all worked out pretty well considering.

I can’t promise that this process will work for everyone, but it was worthy of some serious celebration on my end.

Happy saving!

This entry was posted on Monday, July 5th, 2010 at 11:53 am and is filed under Blog the Muse. You can follow any responses to this entry through the RSS 2.0 feed.