Matthew,
With respect to "sonance" (consonance and dissonance), one can be more specific, I think. The Helmholtz consonance theory states that dissonance is perceived if the rate of beats generated by two partial tones of almost equal frequencies is in a certain range, approximately
between sqrt(f) and 2*sqrt(f). For instance, if the the average frequency f of the two beating partials is 2500 Hz, then beat rates ranging from 50 to 100 beats per second are especially disagreeable. That theory does not explain the extraordinary beauty of the minor and major thirds composed of harmonic complex tones in the female-singing pitch region. In the mentioned article [R.F., "Psychoacoustic experiments ...", Canadian Acoustics Vol. 35 No. 3 (2007) 38-45] and also in my book "Meantone Is Beautiful" (2002) I have proposed "condition b", an addition to the Helmholtz theory: consonance is enhanced if in the excitation pattern generated by a two-tone on the basilar membrane of the cochlea there are few or no wide gaps (in other words, if the BM is stroked by something like a flat hand, and not by a fork).
Reinhart.
----Ursprüngliche Nachricht----
Von: mccabem@xxxxxxx
Datum: 25.09.2010 22:54
An: <AUDITORY@xxxxxxxxxxxxxxx>
Betreff: Re: Dissonance with integration?
Martin,
I think you are forgetting the importance of mental states and priming in
music perception. Certainly there are biological "bottom-up" processes
that you suggest below, but i think we are using the same words in
different languages here...
"Pitch" and "chroma" to me are nameable bits of musical information -
without higher order cognitive functions, pitch and chroma cannot be
categorized or sorted -- or indeed, even recognized. species with more
highly developed cognitive function have octave recognition, others do
not... it's escaping me who did the study on Tamarins' preferences for
consonance/dissonance...
i think you are referring to the auditory system's capability of
extracting surface-level features such as frequency relationships and
harmonicity -- "Pitch" is a cultural phenomenon, as Kevin has suggested.
Frequencies and harmonic relationships are, more or less "physics" that is
processed by the auditory pathway until its arrival at the auditory
cortex.
speaking of which -- have you read the paper about plasticity in tonotopic
maps? perhaps this has something to do with perception about consonance
and dissonance. i'll see if i can find it... the finding was that in A1
the tonotopic map is not organized as once thought, is different across
individuals, and has L/R/ lateralization differences...
are we speaking about consonance as "Harmonically related" and dissonance
as "not harmonically related"? i can see that as a point of confusion
between disciplines.
I agree that there are hard-wired responses to acoustic phenomena
(fight/flight/etc), but music is, for the most part, unnatural. Using
comparisons to animal calls is interesting, but at the end of the day, not
the same thing. without cognitive processes such as memory, music
perception would be fleeting. Mental state has as much to do with
receiving musical information as the timbral content of the sound...
regardless of the style or level of dissonance the particular culture has
imparted on particular organizations of sounds -- also a "top-down"
process.
i guess i'm confused as to why it can't be looked at both ways...
-m
---------------------------------
Reinhart Frosch,
CH-5200 Brugg.
reinifrosch@xxxxxxxxxx .