source file: mills2.txt Date: Fri, 3 Nov 1995 09:00:50 -0800 From: "John H. Chalmers" >From : mclaren Subject: Larry Polansky & adaptive tuning --- Long ago in a galaxy far away, Larry Polansky wrote an article entitled "Paratactical tuning." In it he posited a system of dynamic tuning which adaptively changes the size of interval classes depending on musical context. While in one sense this is a sophisticated software method for facilitating modulation in JI (similar to such arrangements as Harold Waage's logic-gate just intonation system which detected fingering patterns and retuned intervals so as to produce maximally beatless chords regardless of key)...in another sense Larry was getting at something much deeper. Paratactical tuning is far more than mere dynamic retuning to produce the "best" chords according to the location of the current 1/1. Because Larry P. leaves it pretty much open-ended as to what the criteria are. They could be "which 1/1 are we on?" but they could easily be something else. Once it's all in software, the rule-set that determines how JI intervals shift can respond to a lot more than local key center...for instance, the software could respond to the player's dynamics, or the shape of the melody line, or the nature of the harmonies being played. More: Larry suggests that the criteria for the rule-set geoverning the adaptive tuning might be open-ended as well--possibly even dynamic. One could imagine, for instance, an adaptive tuning which morphs JI intervals from "plaintive" to "luminous" or from "tense" to "resolute." (As William Schottstaedt has so dextrously done in an intuitive fashion in the fourth movement of his composition "Water Music," albeit in that case moving from 13-TET to Pythagorean. If you haven't heard this composition, you're missing a truly spectacular piece of music.) As a first advance, this leads directly to a systematization of Lou Harrison's "free style" of composition, in which successive intervals are tuned not with reference to a fixed 1/1, but with respect to the previous note. Clearly such a practice produces a much more complex system of just tonality--but, as Boomsliter and Creel pointed out, this might also more closely mirror the way the average person hears music. Our hearing appears to be relative rather than centered on an absolute 1/1 (except for those rare listeners with absolute pitch), if the psychoacoustic evidence is to be credited. However, Larry's idea of adaptive tuning goes much further than simply the B&C idea of the "the long pattern hypothesis." While useful, B&C's concept of melodic sections moving between separate and distinct 1/1s is in itself limiting because it posits simplistic patterns of linear movement twixt striaghtforward JI melodic contours, overtone structures, etc. When combined with the concept of morphological metrics, Larry Polansky's paratactical (or adaptive) tuning really begins to open a *lot* of new doors. For instance, changing one morphological metric into another introduces (on the level of the melodic phrase) a complex set of requirements between vertical and horizontal interval-relations. As Larry so insightfully realized, this is an ideal case for adpative tuning: and with sufficiently complex software, paratactical tuning does indeed seem the ideal solution to this ever-present tension twixt vertical and horizontal relationships in the context of changing from one vertical or horizontal morph to another. But when you throw in the concept of changing from one *timbral* morphological metric to another at the same time....! Then, adaptive tuning--in this case extended downward into the micro-level of the individual overtone--is the *only* practical solution to the complexities introduced. Because of the extraordinary explosion of interactions between timbre, vertical and sequential structure in tihs case, a set of adaptively tuned overtones offers by far the simplest solution. (Jean-Claude Risset and John Chowning and Bill Sethares and James Dashow have produced some compositions which use elements of this technique: the pieces are astonishingly beautiful, yet only a preliminary step toward the total integration of timbre with harmony. Because of the incredibly cumbersome nature of "doing it all by hand" in Csound, further advances along this line seem likely to be made only with the aid of some sort of automated morphological metric software.) However, there's even more to Larry's idea than this. At the highest level, adaptive tuning can be thought of a way to generate a single "composite" instrument from a number of subinstruments. If you think of each dynamically-retuned section of the score as a specific subinstrument, the real depth of Larry's idea becomes clear. In order to wander over the entire solution space you'd need huge numbers of actual physical instruments--not a reasonable solution. Thus Larry substitutes *virtual* instruments. And adaptive tuning shows its true power by effect switching betwen those virtual instruments instantaneously: the net result is infinitely more efficient & flexible than either the Partch solution of limiting the composition to a single key, or the Harrison solution of requiring the performer to be painstakingly exact in moving from one just ratio to another as well as keep in hi/r head where the melody has been and where it's going to (in terms of moving 1/1s). Larry has written a composition that puts some of these ideas into practice. Due to be premiered in Japan, it looks to this old score-reader like another remarkably beautiful JI composition, yet (as mentioned) it's more than that... Larry's upcoming piece promises to significantly advance the state of the microtonal art. --mclaren Received: from eartha.mills.edu [144.91.3.20] by vbv40.ezh.nl with SMTP-OpenVMS via TCP/IP; Fri, 3 Nov 1995 19:14 +0100 Received: from by eartha.mills.edu via SMTP (940816.SGI.8.6.9/930416.SGI) for id JAA00103; Fri, 3 Nov 1995 09:14:02 -0800 Date: Fri, 3 Nov 1995 09:14:02 -0800 Message-Id: Errors-To: madole@ella.mills.edu Reply-To: tuning@eartha.mills.edu Originator: tuning@eartha.mills.edu Sender: tuning@eartha.mills.edu