When I use the Amplication “dialog box” to amplify a MP3 file to the maximum level without distortion (the optimum level) and then export the amplified file to a folder, the resultant MP3 in the folder does not maintain the same “optimum” amplification. How can I go about this issue? What am I doing wrong?
What am I doing wrong?
Using MP3?
MP3 gets its small file sizes by causing very careful, patented distortions in the show. It’s not a perfect sound format.
While the show is in Audacity, it’s in super high quality internal format, but when you MP3 export, lame applies the algorithms and processes that give the small files. The show inside Audacity and the show in your MP3 are different and the only way to minimize the damage is to stop compressing so hard. Try exporting the show at the highest possible MP3 quality, I think it’s 320. That will minimize the damage even if it doesn’t completely go away.
If you have to stay at the same filesizes, you can’t, at least not in Audacity. If you only need very simple cutting or effects, you might be able to use one of the Pure MP3 Editors that don’t have to go through this double conversion. Scroll down in this link.
If you do need filters, effects and extensive production, you need to start with the original WAV or AIFF files, not MP3.
Koz
Thanks for the explanation. Now I understand what’s going on and I can do experiments accordingly. - SSen
I don’t think this is a big deal. We know MP3 is lossy, but it can often sound identical to the original and unless you are designing an MP3 encoder there’s not much point in worrying about the details of exactly what’s happening to the data.
With MP3 compression some peaks are increased and other peaks are decreased. The MP3 file itself isn’t clipped (MP3 is not limited to 0dBFS), but your DAC may clip if you play at full-digital volume.
As far as I know the slight short-duration clipping caused by MP3 encoding is never audible… i.e. If you hear compression artifacts, reducing the volume before compression to prevent clipping won’t remove the compression artifacts.
If you use a special-purpose lossless MP3 editor the MP3 can be adjusted in 1.4dB steps. If you normalize for 0dB peaks, the peaks will end-up somewhere between 0db and -1.4dB,