editing an .aup file VS .mp3

This may sound like a silly question, so please forgive me I’m fairly new at using the Audacity program. I opened an mp3 file to edit and when I completed what I had to do (normalize) and when I went to close it, I said it would save as an aup file, or the option to export to mp3.

My question(s) is/are, does the exported aup edited file, to mp3 file, cause any unnecessary conversion issues or problems compromising the quality etc. and if so, secondly can the mp3 file be opened as an mp3 file avoiding any potential issues or problems exporting aup to mp3?

So far my experience with this program has been great! It’s an awesome program and hard to believe it’s FREE!!!

Thank you in advance for any help you can provide.

Not a silly question :wink:

Splitting this question into three:

  1. does the exported aup edited file…
    The “.aup” file is only one part of an Audacity project.
    An audacity project has 2 parts. There is a “project file” (the .aup file) and there is the audio data. The audio data is often in a folder that has “_data” at the end of the folder name. There may also be “dependencies”. Please see here for full details: http://manual.audacityteam.org/o/man/audacity_projects.html

  2. does the exported “Audacity Project”, to mp3 file, cause conversion issues or problems compromising the quality.
    Yes there will be some loss of sound quality whenever you export to MP3. This is unavoidable because MP3 is a “lossy” format, but the loss of quality can be minimised by using high bit rate settings for the MP3.

  3. Are these losses “unnecessary”.
    This is a matter of perspective. Audacity always works on uncompressed audio data. There are other programs (such as MP3Split) that are capable of basic editing of MP3s without decoding/re-encoding, but for the extensive editing and processing that is available with Audacity it is necessary for MP3s to be decoded first.
    Re-encoding issues can be avoided by using a lossless format such as WAV rather than MP3.
    Re-encoding issues may be avoided if you are doing only very basic editing, such as splitting a file, by using a program such as MP3 split to edit the file rather than Audacity.

So another possibly silly question, yet I think I already know the answer. So would it make sence to convert the mp3’s to WAV format, open in Audacity, then edit and export to mp3? I’m thinking no, I believe the multiple conversions may cause problems. I’d be converting mp3 to WAV, opening WAV in Audacity (which I believe it would open as a .aup file?), then export back to mp3. By my count that’s 4 file conversions, mp3/WAV/aup/mp3. Actually it’s 3, from the mp3 starting point.

What’s your opinion?, and thank you so much for your help.

Nice try, though.

The act of making an MP3 creates a combination of show music and compression damage. If you make an MP3 out of an existing MP3, you are compressing the compression damage from the first one making it much worse.

If you open an MP3 as WAV, Audacity Project (please, not “aup file”) or any other very high quality format, all you will get is music with really, really accurate compression damage. Making an MP3 from any of these will double the gargling, bubbling compression damage.

The rule of thumb that 32 is for barely OK mono, 64 for barely OK stereo and 128 just good, only works for Original Work – like you playing the xylophone. If you start with already existing damage (like somebody else’s MP3 file) none of those numbers work any more.

“I downloaded a musical MP3 and did some production on it. If I make it the same size as the original, it sounds bubbly and honky. If I solve the honky, the file is huge.”

That’s correct.

MP3 (and cousins AAC, etc) are end-of-the-line delivery formats, not production/editing formats.