I can't help you with an app to do that, but I'd advise you to make a copy of all the mp3s before you do.

Why?

Normalizing won't make them all sound at the same volume. All normalizing does is boost the volume of the entire track so that the highest peak is maximized (or at a preset volume near max).

So if you have one track with a fairly constant volume and another with one huge peak at say the ending or a big hit, when you are done normalizing, the track with the fairly constant volume will sound much louder than the one with the huge peak.

I guess that's why mastering engineers get paid so much.

But if you have the originals and normalize a copy, if it doesn't work out well, you haven't lost anything.

Insights and incites by Notes ♫


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