Audacity Forum

As a new user to Audacity, I created 50+ MP3 files. I now discover that some of them play through only one speaker. Others play through both speakers. How can I adjust some of my MP3 files so the sound comes out of both speakers? (Hopefully, you won't say I have to recreate them.)

Do you have WAV versions of these files?

Yes, I do. That's what I started with.

Oh good. Changing MP3s is not so great because (for most things) it involves decoding the MP3, making the change, then encoding it again, and since encoding as MP3 is "lossy" there is a drop in sound quality each time you do it.

You are going to go through these files and sort out which ones are OK, and which ones aren't.

Make 2 folders - call one "stereo" and one "mono".

For each problem MP3, check the original WAV file - if it plays through both speakers, put it in the "stereo" folder - if it plays through just one speaker put it in the "mono" folder.

When you have done that, if you have any WAV files in the "mono" folder you will need to fix them.

Fixing the mono WAV files:
Open one up in Audacity and have a look at it. If it is a stereo track with a waveform in one channel and a flat line in the other you will need to split the track, delete the flat line track and set the good track to Mono (from the track drop-down menu). Then Export the WAV to the "stereo" folder. (OK, so it's not "stereo", but so long as the track is set to "mono" it will play through both speakers and that is what we are interested in).

Check that this new "stereo" track plays correctly through both speakers.

If this does not fix it, or if the problem seems to be something different, let me know what you think the problem is.

Assuming that you can fix the faulty WAV files - or if the WAV files are OK and it is just the MP3s that are faulty, download and install Foobar2000 (it's free).

Foobar2000 is an audio player - and a really good one - it's pretty basic with dull graphics, but it plays virtually all known audio file types, it's pretty lightweight, and important for us, it can convert files from one type to another. We are not going to use Audacity for encoding the MP3s because Foobar2000 will do it much more easily and quickly.

To convert WAV files to MP3, you load all of the files into a playlist (much as you would with any other media player), but instead of playing them, you tell Foobar2000 to convert them. I can't remember exactly what you have to click and when, but it is pretty straightforward - I think you just right click on the play list and select "Convert", then follow the on-screen dialogue to tell it to convert to MP3.

Thank you very much. I'll give it a whirl.

GB

Steve -- You solution was most effective. Now when we play our files, the sound is so much better. Thanks for your very complete fix to a real head-scratcher.