[LAD] twice as loud

[Albert Graef]

lieven moors wrote:
> ...continuation of truncated mail (does anyone know why this happens?)

Probably it's the second "From" line; looks like your mail client is
confused by this.

Concerning your question: As other have remarked, that is a very
intricate question which is studied in psychoacoustics, so one of the
requisite textbooks on the subject (like Roederer's "Psychophysics")
might be helpful. Conventional wisdom (based on psychoacoustic
experiments) has it that a 10 phon increase (i.e., 10dB SPL, corrected
for frequency-specific sensitivity using the Fletcher/Munson curves or
some variation of that) means double loudness for many people (on the
average).

But of course that doesn't mean that you can just add signals until you
achieve a 10 phon increase and get something twice as loud. If you're
adding signals then you also have to consider masking effects
(basically, spectral components hitting the same critical band on the
Cochlea), so you'll need a psychoacoustic model (same as what gets used
for lossy compression) to get it sorted out.

Albert

-- 
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email:  Dr.Graef at t-online.de, ag at muwiinfa.geschichte.uni-mainz.de
WWW:    http://www.musikinformatik.uni-mainz.de/ag