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Re: Software for loudness equalization?

Dear Dave,
you can try replaygain (http://replaygain.hydrogenaudio.org/proposal/), this web-page includes Matlab-code, I think they use a pink-noise presented at 83 dB as a reference, replaygain is used to achieve an equal loudness percept for e.g. mp3-recordings. If you have access to adobe audition you can use the "group waveform normalize" function. Both, replaygain and adobe use (approximations to) equal-loudness contours, in adobe this is optional.
Hope this helps

2012/4/10 Dave Benson <davehbenson@xxxxxxxxx>
Dear list,

I have a largish (600 item) collection of short musical sound files that I'd like to equalize in loudness. Specifically, I'd like to scale each file so that the peak of its loudness function is equal to a particular value, in sones, that I specify.  Is anyone aware of a software package that can perform this sort of equalization?

I've found several implementations of loudness models online (see below) but they all seem designed to solve a slightly different problem. Namely, they take audio files as input and produce loudness values as output.  I'm interested in the inverse operation: taking a target loudness (and a set of unscaled files) as input, and producing set of scaled audio files as output.

I'm aware that this problem could be solved using an iterative technique (i.e., by repeated adjusting each file's scaling factor until its loudness is close to the target), and writing a script to do this would be relatively straightforward.  Before writing it, though, I wanted to make sure that a similar script (or perhaps a more elegant solution to the problem) hadn't already been written by someone else in the community.  

Again, is anyone aware of an existing software package for equalizing a set of audio files in loudness?

Many thanks for your help,

Dave Benson
PhD Candidate, Sound Recording department
Schulich School of Music of McGill University

* The loudness model implementations I'm referring to are
- command line utilities from Prof. Brian Moore's lab at the University of Cambridge (http://hearing.psychol.cam.ac.uk/Demos/demos.html)
- Psysound3 (http://code.google.com/p/psysound3/
- the Loudness Toolbox from Genesis Acoustics (http://www.genesis-acoustics.com/index.php?page=32)