file format confusion

In Audacity v.2.2.2, I created a new .aup project, imported an MPEG-1 Layer 3 file and edited it. I now want to export the file so I can add it to my iTunes library. If I export it as an MP3 file will I lose any data? If that is a reasonable way to export the file, which Channel Mode should I select: Joint Stereo or Stereo? Thank you.

MPEG-1 Layer 3

That’s the full family name of MP3. Its daddy was a video.

If I export it as an MP3 file will I lose any data?

Yes. MP3 production always loses quality which is why it’s recommended that you not do production in MP3.

However, if you pick a very high quality MP3 export, such as 256 or 320 you will probably not be able to tell what you did. Of course, the file size is going to go up.

which Channel Mode should I select: Joint Stereo or Stereo?

Does it have two blue waves? I don’t think it makes a lot of difference, just the efficiency of the file goes up and down slightly. If it’s mono, I think Joint Stereo is good. I think that’s the one that automatically knows not to try and force stereo.

Koz