Free tools for normalizing the volume within a single track

Question

How can one normalize the volume within a single track to reduce the amount of volume between the softest and loudest parts? (My use case is classical music where there are often big differences between the softest and loudest parts in a piece).

I have tried tools like the normalize in Audacity, but this does not change the dynamic range. On the the MP3Gain website, I see reference to a tool called MP3Gain Pro, which by the description, seems to do it:

"Mp3Gain PRO" does volume normalization inside the mp3, not just between separate mp3s. So if you feel a song is too quiet at the beginning (or middle, or end), then it can boost the volume just for that part.

This sounds like it would do exactly what I want, but MP3Gain Pro is not a free tool. Can anyone recommend something that will work for Windows or Linux?

Answer 1

Normalisation only raises the overall volume uniformly (the soft parts will be louder, but so will the loud parts). What you're looking for is dynamic-range compression, and I think there's a plug-in for that in Audacity. I'd advise you to learn a bit about the different controls on a compressor before you get stuck in.

Answer 2

Audacity does normalising but it sounds like what you want is a peak limiter. Try the Yohng W1 Limiter, which is modelled a a well-known and (possibly overused) plug-in. It doesn't look all that, but it does the job nicely.

You should also try a compressor, but you'll need to use it really carefully on classical material.