Purchased MP3 files import WAY over maximum volume allowed by Audacity

I have purchased many MP3 files from Amazon. When I import some of them into Audacity to normalize volume, Audacity has already cut off the waves at the top and bottom, suggesting that the purchased file was recorded at a level that was WAY too loud.

Is there any way to have a custom volume setting for imported files so they would arrive in Audacity at their actual recorded volume? I would like to normalize them myself, rather than have Audacity do it automatically. (I’m not sure what Audacity is doing.)

Thank you.

This gets complicated…

The MP3 is PROBABLY NOT actually clipped] (assuming the CD wasn’t clipped) and Audacity itself uses floating-point data which essentially has no upper or lower limits.

Audacity will “show red” for POTENTIAL clipping if you have “show clipping” enabled. Audacity is just looking at the levels. It doesn’t look at the wave shape. You can get false positives or false negatives. If you have a clipped file and you lower the volume (Amplify with a negative value) you can “hide” the clipping from Audacity but it doesn’t fix the distortion.

Some CDs ARE clipped to “win” the loudness war.

MP3 can also go over 0dB without clipping. CDs and “regular” WAV files are hard-limited to 0dB and they will clip if you “try” to go over.

Your DAC (digital-to-analog converter) is also limited to 0dB so if your file goes over 0dB and you play it at “full digital volume”, you’ll clip your ADC. Lowering the digital volume or applying ReplayGain (which normally lowers volume) can prevent clipping of the DAC.

As you may know, MP3 is lossy compression. The wave shape changes and some peaks get higher and some get lower. The new highest peaks may go over 0dB but they are not clipped yet (if the uncompressed original wasn’t clipped). If they go over 0dB and you export to regular (integer) WAV, they WILL be clipped. Bu t if you lower the volume before exporting you can prevent that.

The file can clip your DAC but I don’t believe the slight clipping is audible. If you hear distortion, the original is probably clipped/distorted. If you’re hearing a compression artifact, it’s probably something else.

…And at this point, you’ve already chosen, or accepted, lossy compression. :wink: It can often sound identical to the uncompressed original (in a proper blind listening test) but it it is technically imperfect and it may sound imperfect.

FYI - When you open an MP3 in Audacity (or any regular audio editor) it gets decompressed. If you re-export as MP3 you are going through another generation of lossy compression and some “damage” accumulates.

You may not hear any quality loss but it’s something you should be aware of.

Sometimes you don’t have a choice, but you should minimize the number of times it’s re-compressed.

There are special-purpose MP3 editors, like Mp3DirectCut, that can do some limited editing without decompressing.

This topic was automatically closed after 30 days. New replies are no longer allowed.