My premise is that there are left-brain aspects of music, and right-brain aspects, that can occur independently. My beginning here owes much to the late Jonathan Kramer's awesome book The Time of Music. The left brain, generally speaking, is verbal, and works by means of logic and analysis and categorization, and also keeps track of time. The right brain, timeless and intuitive, perceives expressive nuance and qualities that are more difficult to put into words. In conventional classical music, or perhaps conventional any music, the LB and RB aspects tend to support each other, though divergenges can be used to create tension. For instance, a tapered decrescendo (RB) at the end of a movement will support a coda's role of being the end of the piece (LB, since time sequencing is processed by the left brain); or a crescendo can serve the same function, but one or the other tends to happen. (A mezzoforte ending without ritardando is perceived as an interruption.) The transitional theme in a sonata has the logical role, which we perceive (LB) in the harmonic syntax, of creating the tonal ambiguity needed to move to a new key; this is normally accompanied by RB qualities of greater rhythmic restlessness and increased momentum, so that the music's expressive quality mirrors its logical function. Frequently the composer's ability to match the expressive feel to the syntactic role is what makes a sonata form more or less compelling. For instance, what seems a little Biedermeier-ish and self-indulgent about Hummel at times is that his transitional themes can be languid and unhurried, and without the razor-sharp harmonic directedness that makes Beethoven's transitional areas so taut and gripping. There is a slight mismatch between mood and logical function.
Of course, classical composers very often intentionally mismatch expression and meaning, as Haydn likes to do by beginning a string quartet with what the right brain clearly recognizes as a closing gesture:
This (from the Op. 50/6 String Quartet, and it's one of Kramer's examples) sets up a cognitive dissonance because the left brain knows that the piece is only beginning and that this theme has to fulfill an opening role, while the right brain feels it as a finalizing gesture. I think Beethoven does something similar in the harmonic rhythm of his late piano sonatas: the left brain expects the phrase structure to be defined by the harmonic syntax, but the unpredictability in the timing of his chord changes creates an expressive dissonance, harmony refusing to support the phrase rhythm. In any case, we can posit a kind of musical normalcy in which expressive (RB) and logical (LB) qualities are closely associated in time, with here and there a momentary disjunction to tease the brain and create tension.
There is a branch of (let's call it for now) experimental music, however, in which LB and RB qualities are radically separated out. The classic paradigm for it is Reich's Come Out, or perhaps equally Piano Phase. Most people who listen to Come Out, probably even for the first time, know that the phrase "Come out to show them" is going to go out of phase with itself. Since the left brain can grasp this at once and anticipate it, from a logical point of view there ought to be no point in listening to the piece. But what happens is that the texture of that process is completely surprising, and that rhythmic and timbral illusions happen as microbits of the phrase start to perceptually associate with each other. It's fascinating because you know (LB) that the process is a simple linear one, yet you hear (RB) unexpected patterns that you couldn't have anticipated. The dissonance between cognition and perception is not just momentary, but globalized across the duration of the piece.
Examples are easily multiplied. JLA's Clouds of Forgetting, Clouds of Unknowing follows a linear progression from minor seconds in the first section to major seconds, then minor thirds, mixed minor and major thirds, and so on up to major sevenths at the end. (I kid John that when I start hearing tritones I know his pieces are half over, though it's only true of a handful of them.) If you know what's going on (and you can figure it out by ear if you listen a certain way), you can keep mental track of the form of the piece. But the sections are so long, and so vaguely textural, that more commonly the mind gives up trying to keep track and can only lose itself in the sensuous surface. And there are other complications: the textures and orchestrations move back and forth among different phases in a huge palindrome that your left brain could track if you were intent enough on it. But again, what's more interesting is knowing that the music has some kind of order, but losing yourself in the vast color fields of tremolo and arpeggio. There is a left-brain aspect to the piece and a right-brain one, each intriguing, but they operate separately, and not in tandem.
This is not merely a Downtown or post-Cage phenomenon, either; I think (and Carson and I were noting the resemblance) the same principle underlies Babbitt's and much serial music. For instance, All Set runs through every permutation of the groupings of the six solo instruments. If you have the kind of brain trained to count cards in blackjack, you could conceivably keep track of the groupings as they go by and predict the timing of the piece's ending. Of course, probably nobody listens to All Set this way. The piece is a riot of wildly changing lines and textures, but one thing that adds to the enjoyment of it is that we know it's not just a crazy random improvisation, that there's really a fanatically rigorous symmetry to it of which we're hearing the results that are too complex to track mentally. Right-brain aspects of the piece are virtually random, but our left brain tries to get us to squeeze the phenomena somehow into the order we know (if only by reputation) is in there somewhere.
Now, I think it's safe to say that there are listeners for whom this mode of listening is just never going to be enjoyable. They're used to tons of music in which the expressive and the logical go hand in hand, and if you grab those elements and hold them apart at maximum distance, their brains just won't derive any pleasure from it. As a non-musician friend once said to me about such a piece, "I'd call it art, but I wouldn't call it music." The bit of fun that Haydn had opening a string quartet with a closing gesture has been expanded into a joke whereby the entire piece is not what it seems. Clouds of Forgetting sounds like undifferentiated sheets of arpeggios: it is actually a linear interval progression superimposed over a textural palindrome. All Set sounds like rowdy chaos: it is actually a fanatical symmetry carried out on every possible level. Come Out sounds like a series of complexly related rhythmic patterns: it is actually a mechanically linear phase relationship. One could take examples from Niblock, Glass, Ashley, Xenakis, Tenney, Polansky, Michael Byron, and much other serial or process-oriented (post)minimalist music. Lief Inge's 9 Beet Stretch is a prime example: it's just ambient noise until someone tells you it's Beethoven's 9th slowed waaaaay down.
One way pieces in this category differ greatly is the extent to which we are tuned into the left-brain idea; it's much more obvious in Come Out than in All Set. But the idea can influence the way we listen even if we're only vaguely aware of it. I listen to Music of Changes differently than I do to the Boulez Third Sonata; I know Cage's notes are the results of a gobal chance process, and that on some level Boulez chose, or somehow placed, each note individually. The distance between sound and idea can also vary infinitely. At some point, perhaps, the sound and idea grow too unrelated so that creative tension is dispelled, and that point may differ for various appreciative listeners. An argument can be made that Clouds of Forgetting can be enjoyed merely sensuously without one even intuiting the underlying organization, but while some are willing to simply "experience" without understanding, I think in general there's something in us that makes us want our music to make sense, no matter how "meta-" and oblique that sense might be. In any case, I'm not drawing any distinct lines between genres, but using sonata form and process pieces as two extremes that can be clearly differentiated. I can't even guess where my own music lies along this continuum.
"It's only as good as it sounds" is a favorite motto of mine, but I am too much a new-music insider to be immune to the pleasure of feeling the cognitive dissonance between how a piece sounds and how I know it was written, trying to hear through the notes the structure that I've been led to believe is there. If we don't recognize the final-cadence gesture of Haydn's opening, we miss his endearing witticism, but if we don't know that All Set is an elaborately precise structure, we miss the joke of the entire piece. And, to venture back into an old and allegedly discredited terminology for a moment, it seems to me (as I wrote in Music Downtown) that the willingness to separate the sound and the idea of a piece and let them complete each other in the listener's mind is something that Uptown and Downtown composers shared in common, opposed by the neo-Romantic Midtowners in-between who clung to a more "intuitive" (that Midtown word par excellence) union of expression and meaning.
I don't think I'm saying anything particularly new, nor introducting concepts not in vernacular use. But I do think that a lot of music lovers and a lot of composers think this "boring" brand of music in which the underlying idea is so far from the surface is kind of insane, and that we need a vocabulary for clarifying what those of us who enjoy it hear in it. I also think we need to understand how it works in order to compose it better. Both sides of our brains clamor for fulfillment from music, and Haydn and Adams (and Niblock and Young and Glass) both grant it, even if the difference in scale is so vast as to constitute a difference in kind. Perhaps some people's brains are simply not wired to enjoy such music: we have no reason to be convinced physiology doesn't play a role. When we fail to make the distinction explicit, though, I think we set up an undifferentiated new-music world in which Clouds of Forgetting seems obviously more boring next to, say, the Christopher Rouse Trombone Concerto - whereas, in fact, I think its pleasures are greater, though they lie across a different, and perhaps non-obvious, mental plane. [UPDATE: And why does it seem boring? Because the left brain, which keeps track of time, can't find anything to latch onto - though not necessarily because there's nothing there.]
...You have evidently aimed at impressionistic word pictures, striving to avoid the commonplace and trivial. Whether your musical inspiration has been able to meet the demands you have placed upon it is an open question, and one I should like to defer until I hear your sonata adequately performed. My present impression is that, in spite of the great amount of work you have put into this composition, the fundamental inspiration and glow are lacking. It is, however, a very interesting work. I question whether in the interest of musical beauty such an effect as you call for in page 25 [clusters played with a stick of wood] is good. A "strip of board" does not appeal to my sense of artistic piano music....
...As for the "music," I confess with thousands of others who have seen it, that it is incomprehensible to me. I do not ridicule you, I do not criticize you, philistine-like, because it would do no good anyway, so all I venture to say at this time is that I hope you will find pleasure in the satisfaction of understanding what you yourself have set down in the seventy pages of your work! No doubt it took a great deal of time to prepare all that notation... Were you not, perhaps, trying to put into "form," expressions that were entirely (to use a term of our Theosophical friends) ASTRAL - with a modus operandi that granted only PHYSICAL possibilities? This is not sarcasm because I do not mean it as that....
I wish you to know that I do not take your work lightly. I say, frankly, that I do not like this manner of sound-association, for I am too fully grounded in the habits (I admit that they are, to some extent "habits") of the classic methods. To my mind, these classic methods are correct ones for I find them, in every detail, confirming the eternal physical laws which govern tone as well as stone. But I am not, in conviction, a heartless and brainless conservative, who recognizes the "Last Word" in anything that Bach, Beethoven, or Brahms have said in tone - no, nor Ives. And therefore these newer methods, or experiments, interest me keenly. And, since I am absolutely convinced of your sincerity, and see many admirable evidences of that logic, which is a part of my pet physical law, in your work - note that I hesitate to call it "music," for I believe in accurate definition - I declare that these experiments of yours interest me particularly....
I was very surprised to receive such a book from a musical composer. I showed it to a friend of mine (one of the Boston critics) and called his attention to certain striking passages. He was most interested and enthusiastic but said: "Depend upon it, this fellow is a bad composer - good composers are usually non compos mentis on every other subject."
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