I have thousands of MP3 files… from various sources over many years.
If I had to normalise each one individually, then export to a new folder, it would take me a very, very, long time.
Is there a way to get Audacity to “Batch Normalise” them all to the same level. Ideally putting the normalised tracks into a new folder (just in case anything goes wrong in the process).
The process would also need to dig into Artist->Album subfolders to get to most of the tracks.
You won’t. But you are using the wrong tool, because you will degrade the MP3 files when you re-encode them in Audacity. mp3DirectCut will normalize the files for you without re-encoding.
Is there a way to get Audacity to “Batch Normalise” them all to the same level.
Note that normalizing won’t make them sound equally loud.
If you want them to sound equally loud, try [u]MP3Gain[/u] or use a player that supports [u]ReplayGain[/u], or if you have Apple hardware or ITunes, switch-on Sound Check.
MP3Gain and ReplayGain can batch process all of your files, or there is an AlbumGain mode where one album/folder is processed at a time to volume-match the level of the album as a whole while maintaining the relative loudness difference between quiet and loud songs on an album,
Note that all of these loudness matching techniques will make many/most songs quieter. That’s because many quiet-sounding songs are already normalized (maximized), so the only way to match volumes is is by setting a lower target level, making the loudest songs quieter.