I applied MP3Gain to all of my LAME APS MP3s several months ago. Lately, I have been mixing in files from other codecs (AAC and WMA). I cannot mix these songs in with the MP3s on playlists and portables however because they are so much LOUDER than the MP3Gained MP3 files.

Is there a quick way to undo the MP3 gain on all my MP3s without having to put all the files in one folder?

My current folder heirarchy is Drive Letter/MP3/Artist Name/Album Name. I have over 1000 albums from over 500 artists. It will take forever to go folder by folder (as it did to apply album gain!). Is there a way to just select my MP3 folder, and have all folders underneath be selected as well - and hit un-do????

Any help is appreciated!!!

(In the future its replaygain only!!!!!)

FYI - in case no one is responding because there is already an MP3Gain guide in this forum - I already reviewed it. I could find nothing on best way to undo. I think I know the best way to do this, but want to be sure before I affect 7,000 files.

in command prompt in your base dir

sweep mp3gain /u *.mp3

you need sweep installed

If you're using a later version of MP3Gain (not sure when they added this feature), you can load all your MP3 folders (by selecting the parent directory of all of them) and selecting Modify Gain - Undo Gain Changes. This will only work if the gain changes you applied were with a version of MP3Gain that would have written undo info into the MP3 header. If not, this won't work.

Try with one folder and see if changes are undone as you'd expect. If you've only used one version of MP3Gain, this will tell you if you have the required undo info in the files.

Thanks ScorLibrarian. Almost all of my files were 'gained' with the latest version of MP3Gain. There may be a few hundred that were not.

I'll give it a try.

If I modify levels by mp3gain not only once (i.e. +1.5db, then -3.0db, then additional -4.5db) and have the changes undone afterwards, is it just the last step that is undone? Or does mp3gain undo all of its several actions?

mp3gain supports AAC gaining, albeit experimental, and about WMA, you should do better without it.

I ran mp3gain last year when I got my first ipod. At the time I had some 4000+ songs and although it took some time to process I'd give it an A+. Since that time I have added my brothers CD library to my folder and the songs now are close to 6000+, I ran mp3gain again on the entire library without thinking (duh) that it might impact the mp3's I'd already processed. Everything seems to sound just fine after running some mp3's twice. Have I really screwed up my library? Should I reprocess and undo my mp3's tags or am I too late? I am not a technical person and appreciate any advice you guys can offer. Thanx

It should have remembered that those mp3s were already adjusted.

Thank you, I was hoping that was the case. I remember the window indicating the change in Db levels was set to 89 on all the songs that had been processed and only the new songs showed an adjustment up or down and as I said everything sounds fine (as long as I don't use soundcheck).