Sound outage, but waveform looks normal

[ibedi]

I'm on Windows XP with Audacity 1.2.4

I have used Audacity several times and never had this problem. I imported several audio files (wav) into one project last night. I had my intro, the bits and pieces of the body of the show's audio, but it was too late for me to record my outro. I saved the project on my desktop. Tonight I opened it up, added some more audio tracks and when I started it at the beginning everything was fine until I got to one imported stereo track and in the middle of it was a huge dead zone. It was as if my track had flatlined...but it hadn't! My waveform looked perfectly normal. It was silent for several seconds, then the sound came back, just as if I'd turned the volume all the way down and then back up.

I re-imported the file and had to re-tweak it. I continued listening and then another track did the same thing. It's a file that was a nightmare to edit. Please, please somebody tell me how to fix this problem!

Much appreciation,
Diane

PS. I tried to search, but I'm too wigged to think of decent search terms.

[waxcylinder]

You have almost certainly delete or moved one of the original WAV files that was imported to create the Audacity project. When Audacity "imports" WAV files it doesn't actually import them but rather creates a link to the dependent file. The waveforms are drawn from info contained in the Audacity project file - so that is why is still looks ok. This is not very well documented - and many people fall into this elephant trap, you're by no way the first person this has happened to!

If you can put the original WAV files back in their original position your project should still be ok.

(Note that this does not happen when importing MP3 as Audacity has to "add water" to uncompress the file - and in doing so makes an internal copy).

WC

[ibedi]

Thank you! Maybe I did move things.

Is it true that you end up with better sound quality in the long run if you import files as wav? Seems like I read that somewhere.

[kozikowski]

Microsoft WAV (wave) format is uncompressed and provides excellent quality depending on the encoding numbers you chose. (48000 sample frequency will provide higher quality than 44100). WAV files are very large and they don't change.

MP3 (MPEG1, Layer 3) sound is compressed and damaged. MP3 is a destructive compressor. It analyzes your show and decides what parts you're never going to miss anyway--and throws them away. MP3 has several sliders only one or two of which are brought out for you in Audacity. You can tell MP3 that most of the show is "extra" and the result will be complete garbage. You can tell it to save everything and it will produce a very large file that sounds perfect.

Every time you edit an MP3 sound show, you get two more layers of distortion, not one. Audacity has to convert MP3 to WAV, edit it, and convert back.

The up side, of course, is that MP3 files can be made really small compared to WAV files. So capture, produce, and edit in WAV for little or no damage, and export to MP3 to listen on your iPod.

Koz