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Way to quantify degree of loudness-war impacts? (not loudness itself)
Porcus
post Jul 21 2012, 15:52
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I am not asking for a utility that computes some average loudness measure (like ReplayGain). (Edit: Argh, thought I was clever to avoid the quotation marks " and ', in order to keep the board from cropping the subject. Forgot about the slash.)


Rather, I am asking whether there have been developed reasonably good measurements -- and utilities implementing such -- for scanning for “loudness war victims”. E.g., criteria like
- dispersion of amplitude (e.g. standard deviation), over some (moving?) average
- distribution of signals near the digital 1.0000 to identify brickwalling (hard or not-very-soft limiting)
- every track on an album boosted to about the same maximum


Of course it will vary over musical genres, but a model that could scan a batch of subjectively “similar” music and with a reasonable accuracy (i.e. sensitivity/specificity) detect those “bad remasters”, would be a good start.


Anything? Anyone?

This post has been edited by Porcus: Jul 21 2012, 15:57


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Notat
post Jul 27 2012, 20:17
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I see it, there are actually two ways the loudness war affects recordings:
1/ Short term limiting removes transients
2/ Long-term compression or gain control reduces dynamics

Are you interested in (1) the signal processing tricks that make recordings louder while attempting to minimally degrade their subjective quality? Or are you interested in (2) the production aesthetic of unrelenting sound?

For (1) I think you want to measure peak to average ratio. Since it is safe to assume that the peak level for all modern tracks and albums is now invariably the same (0 dBFS) measuring average level alone gives you the answer. Those who suggested an LRU measurement are not wrong.

For (2) the EBU 128 standard introduces a concept of loudness range (LRA) which is a measure of the long-term dynamics.
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