source file: mills2.txt Date: Thu, 29 Aug 1996 15:18:11 -0700 Subject: Resumption of Posts from Brian From: John Chalmers From: mclaren Subject: psychoacoustics versus aesthetics -- In tuning digest 755, John Chalmers wrote: "The JI versus ET or nj-net debate is unlikely to be resolved, especially since Roberts and Mathews found that there are two types of listeners, those that prefer JI and those that prefer the richness of intervals tuned sharp or flat in triads. Frankly, given the over-learning of 12-tet that musically trained subjects will have been subjected to and the self-selection that musically naive persons will have undergone for the lack of musical discrimination abilities, I tend to be skeptical of many preference studies. My advice is for composers and performers to use the tuning they find best for their musical purposes." "I suspect that their audiences will usually agree." -- John Chalmers This advice for composers and performers seems sound and accords with common sense. However, the rest of John's post reflects a troubling misunderstanding of the psychoacoustic research. If someone as smart as John Chalmers is unclear on these points, it's clear that explanation is required. The study of triadic tuning preference cited by John Chalmers is not in the same class with the rest of the pscyhoacoustic research which I have quoted. Properly speaking, the Mathews/ Roberts studies on "pure" and "rich" listeners belong to the subset of studies on music aesthetics. Such studies are seldom done nowadays because they are fraught with peril: as John Chalmers points out, it's unclear whether a test of interval preference indicates (A) cultural brainwashing or (B) innate proclivity for this or that tuning. This applies to aesthetic "preference" studies of Asian, African, South American tunings as well as to "preference" studies of western 12-TET intervals. I have seldom cited such aesthetic research because of the potential problems. In particular, Carol Krumhansl's studies seem to be deeply flawed because of their inherently aesthetic bent--Krumhansl talks about "western tonal hierarchies," but it's not clear whether her data are produced brainwashing among the test subjects or some innate supracultural tendency. (Krumhansl's attempts to address this issue raise more problems than they solve, inasmuch as it's clear that Krumhansl actually believes that Indian musicians use *exactly the same pitches* as the white notes of a Western piano. Put on *your* CD of Indian music, and see if *you agree.*) Much of the bias could even be generated by Krumhansl's test structure. I'd like to see Krumhansl's probe-tone tests repeated for high-limit JI scales and exotic high-limit probe tones. My guess is that the results would be *radically* different. By contrast, the studies I have cited are *not* concerned with preference. I have not talked about "preference" since tuning digest 28 (& if the word crept into my posts, it's the result of my falling into bad habits--in any case I've endeavoured strictly to avoid such prejudicial and inaccurate language). Most psychoacoustic studies do not seek to uncover "preferences." Modern psychoacoustic studies are concerned, rather, to compare what the *listener perceives* with what the *instruments measure.* To say (as Mathews and Roberts do in one single isolated study) that some listeners prefer triads tuned with plenty of beats while other listeners prefer triads tuned as beatless as possible...well, that's one thing. But to say, as 99.99999+% of modern psychoacoustic research does, that listeners predominantly perceive the p5 interval as "pure" when it is sharp of the just value by an average of 5-7 cents for the "perceived" 3/2... That's something *entirely* different. Such studies make no claims about preferences. These studies do *not* say "such-and-such a tuning is a true fifth," or "such and such a fifth sounds better than another `fifth'." They don't even say "such-and-such interval is preferred by listeners." That's a complete misunderstanding of the psychocaoustic research. Instead, what these studies say is that there is a significant persistent universal difference between classes of *perceived* intervals and classes of *acoustically measured* intervals. Such results have *nothing* to do with preferences. When Johan Sundberg points out that "it is important not to confuse with the *perceptual* octave with the *acoustical* octave," this is NOT a statement that the 2:1 is "better" or "worse" than the 1215-cent octave. That's not it at all. That's not the point. "Better" or "worse" cannot be applied to well-designed psychoacoustic experiments. Such experiments seek *only* to quantify the human sensorium--in particular, the human ear/brain system. A good example of how complex this is (and how completely irrelevant and inappropriate terms like "preference" and "better/worse" are to this process of attempting to quantify human auditory percepts) can be found in the controversy over the mel scale of pitch during the early 1950s. The idea behind the mel pitch scale was to quantify pitch perception in the same way Fletcher & Munson had quantified loudness perception during the 1930s for different pitch regions. Because Fletcher and Munson discovered that perceived loudness was dependent *both* on the physical amplitude of the signal *and* on its frequency, someone thought that a similar scale of pitch height might prove useful. Alas, the mel scale proved largely useless because it provided a measure of pitch which changed drastically depending on where the interval was in the frequency spectrum. Moreover, the mel scale applied accurately only to sine wave signals, and broke down when more complex acoustic inputs were tested. It would be a gross error and a complete misunderstanding to say that listeners "prefer" the mel scale for sine wave signals, or that listeners "prefer" a quasi-logarithmic scale for complex harmonic signals. There is no question of "preference"--one scale of measurement is not "better" or "worse" than another. The mel scale is useful for quantifying sine signals, but it is almost never used nowadays simply because the vast majority of acoustic phenomena which psychoacousticians seek to measure and quantify are not sine waves signals. "Useful for such-and-such a class of auditory phenomena" is *not* the same as "better." "Meaningless when applied to such-and-such a class of auditory inputs" is *not* the same as "worse." It's important to be clear about these distinctions, because there's a persistent undercurrent of discussion on this forum which conflates studies of musical *preference* (which might have limited validity, depending on the very limited cultural context one restricts oneself to) with studies of music *perception* (which in general are valid across cultural boundaries, and which furthermore often tell us something basic about the organization and operation of the human ear/brain system). If psychoacoustics were nothing but a set of tests which produce "I like it/I don't like it" answers, the science would indeed be of little concern to members of this tuning forum. That is not the case, however. This is a complete misrepresentation of psycoacoustics. Instead, psychoacoustic studies (when done well--not all such research is competent or adroit) bypass such subjective aesthetic and emotional reactions and reach directly into the details of how the human auditory system operates. This latter issue of some concern when dealing with intonation, since it's vital to disentangle *what the listener perceives* from *the measured acoustic data.* If we do not disentangle percepts from prejudices, questions of intonation are apt to reduce to the trivial level of "such-and -such tuning is more natural," "such-and -such tuning is purer," and so on. In short, into meaningless wrangling over buzz-words. --mclaren Received: from ns.ezh.nl [137.174.112.59] by vbv40.ezh.nl with SMTP-OpenVMS via TCP/IP; Fri, 30 Aug 1996 01:11 +0200 Received: by ns.ezh.nl; (5.65v3.2/1.3/10May95) id AA21387; Fri, 30 Aug 1996 01:12:48 +0200 Received: from eartha.mills.edu by ns (smtpxd); id XA06971 Received: from by eartha.mills.edu via SMTP (940816.SGI.8.6.9/930416.SGI) for id QAA18551; Thu, 29 Aug 1996 16:12:46 -0700 Date: Thu, 29 Aug 1996 16:12:46 -0700 Message-Id: Errors-To: madole@ella.mills.edu Reply-To: tuning@eartha.mills.edu Originator: tuning@eartha.mills.edu Sender: tuning@eartha.mills.edu