Exporting losses

Audacity 2.0.1 from Repo on Ubuntu 12.10 amd64
Hi everyone, just joined today, having spent hundreds of hours on this gem of a program it is time to try and learn something about it the fun way - forums !
My main use is levelling out and tidying up mp3s which normally goes very well indeed.
Recently however there has become a noticeable inaccuracy in the exported result that i am fairly (but not completely) certain was not happening before.
Beforehand i could make one isolated change to the waveform (using all the default settings),
export the file and then reopen it again to find that the new waveform was just as the amended original.
At the moment i find the whole wave form gets changed with peak amplitudes typically .2 to .6 lower and
a period of about 50 ms (near) silence has appeared before the main waves start.
These are smallish issues but i would very much like to regain the previous accuracy ?

If not doing so already, export as WAV and not MP3.

My reluctance with that is having to roughly double the file size, although the day will come when i can afford to upgrade
from mp3 format and wma certainly looks smaller than some of the others such as ogg or flac.

I’m one of the few that thinks Audacity should be more proactive and try harder to keep the peak MP3 export level where it was in the program. Some other programs do better than Audacity, but if you increase the Audacity MP3 export bit rate (click “Options…” when you export) you should find the peak level of the exported file will be more accurate.

Silence at the start of the file is a limitation of the MP3 format. Please see this link http://lame.sourceforge.net/tech-FAQ.txt .


Gale

That is one fascinating link on mp3s by Mark Taylor, thanks for sharing Gale.
Very diplomatic of you guys to get over that at the default 128 kbps waveform exports are going to be significantly different.
I’ll now try and target all those tracks that had multiple edits/exports for a single edit/export.