In Our Theatre

Around the middle of the 20th century, one cutting edge of American poetry found its theatre of operations* in the line, flexible in length (sometimes brief, sometimes extending so far past the edge of the page that it is graphically split and begins again at an indent, perhaps several indents for the long-winded), perhaps tied to a speaker's breath, certainly marking phrases and junctures in the poet's thought.  (See, certainly, Charles Olson's essay Projective Verse.) The line took over the weight which it had previously shared with couplet-ed pairs, stanzas, verses. At the same time, the line in this repertoire, generally speaking, was one without any of the traditional regulatory instruments of rhyme, metre, stress, and/or accent associated with lyric (but each available in principle as an optional local feature.)

Similarly, in some music, particularly the most densely notated, the theatre has shifted from the phrase — usually identifiable by a thorough-going line of some sort and a sustained or continuous pulse and metrical pattern, to the individual measure  (& often that measure is counted in smaller units — which can be very slow indeed  —  eighths and sixteenths and smaller, rather than the quarters and larger pulses of most "classical" repertoire, contributing in many cases — and ithinks not accidentally — to a graphic impression of complexity.)

Of course, there is considerable variation around this tendency towards the measure, some of which points towards phrases rather than measures. In the early — largely percussion and prepared piano — music of Cage, the phrase systems of Harrison, and the predrawn-measures of late Feldman, the measure is the constructive formal unit, replacing the pulse, thus representing a tendency towards extension of the theatre rather than reduction. And in Milton Babbitt's time point system, the single measure, divided into twelve (or whatever) points, is simply the minimal possible space for the presentation of a complete aggregate, with sets that don't fit into a minimal statement spreading out over several measures, consequently creating a reduction in density and/or the pulsed but, in principle at least, ametrical tempo.**

If we do go in the direction of the measure, though, it's probably useful to consider (and often: make clear to performers) whether elements of the traditional pulse-metre-measure-phrase practice, in particular those regular dynamic and durational markers of metric stress, have been preserved or are, in fact, no longer operative.  Does a measure have a pulse-defined tempo and if so, does it extend beyond the single measure, and does that tempo include any pattern of regular stresses or accents (in old song and dance days, when one might have spoken of "movement".)  Personally, I like to keep some of the potential for ambiguity present in the traditional system in reserve.

I've played and sang a lot of renaissance music in which there is a background metre present, but it is not over-determinative, and barlines — often edited in with the intention of assisting musicians more used to modern notational conventions — frequently coincide only weakly with regular metric stress patterns, if at all (one of the important steps in the historical process of opening a distance between lyrical text and tune; such distance to regular patterns of dance steps appears to have come much later — no surprise, I guess because there's more immediate physical danger with missteps than misspeaks.) In my own work, I'm increasingly drawn away from the empty stage of the blank measure and attracted to both lower and higher levels of organization — metrical feet and phrase systems.  But the experience of the measure as the principle theatre continues to be powerful background radiation.

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* Yes, using a military term like "Theatre of Operations" is provocative, probably outright objectionable, and though there is a tradition (Emerson, N.O. Brown, Cage) of objecting to the militarized language to which I feel quite close, maybe it's usefully demilitarizing in itself to extend the use of a term like this to obviously non-military, indeed pacifist ventures.
** This is one of the mysterious topics, for me at least, with regard to serialism (of whatever sort, pre- and post- as well) and rhythm: how do we square the desire for a measure to be a-metrical — that is, without a hierarchy among the internal pulses — with the actual practice in which the notated metre is both a reference and frequently, an obvious source of compositional play?  If I had the time, I'd really like to examine Babbitt's synthesizer code, for example: did he give downbeats any extra intensity in his timepoint pieces? My impression — and I may be altogether wrong about this, so consider it only an impression —  is that the opening towards early music by Webern (Issac) and Krenek (Ockeghem), has not had the charge in later serial rhythmic practice that it once promised.