Timing is everything. That is a statement one frequently hears in a variety of contexts, and although taken to its literal extreme it may be untrue, there does remain a rather significant kernel of truth conveyed. Knowing when to act, or when not to act, is an important part of some philosophies, and the same may be said more specifically of musical production as an activity. At its most fundamental, music organizes time. This is the crucial part of the definition one must use in order to accommodate some of the more unusual postmodern styles, like them or not, and it is the extension in time only which makes music what it is. As Stockhausen illustrated so decisively in his Kontakte, the vibrations making a note and the pulse of a rhythm are only two aspects of the same phenomenon. They are both about time, about alternating act and remission, and so by implication about counting, which is what creates a perception of time. We might not perceive rhythm as a unity, as we do the vibrations of a note, but this is only because of its relative relationship to our perceptual scale, something one might say about other phenomena. Continuing briefly with the cosmological perspective, maybe timing really is literally everything, as one can go on to note that it is the vibrations of subatomic particles which project the firmness of substance. Such remarks become rather distant from our usual reality rather quickly.
The word "tempo" itself is merely Italian for time, suggesting two ideas: The concept has quite far-reaching musical implications, and was established in its present form primarily in sixteenth & seventeenth century Italy. The latter shift can be circumscribed most succinctly as a change from "measuring" to "mood" and along with it the radical philosophical-aesthetic reversal which changed music's perspective from the precision of heavenly motion to the capriciousness of the human heart. One might like to conclude from this that earlier music had no emotion, but what one must remember is that in that time, the movements of the heavens were posited with influence over one's emotional life. The difference, therefore, is one of perspective only, and not of emotional content per se. For some readers, this may be even more objectionable, but ultimately if one is going to appreciate this music, one might as well appreciate it on its own terms. The criticisms themselves go back to sixteenth century Italy, among such famous commentators as Zarlino, and ultimately led to the abandonment of the mensural system for what was deemed a more expressive disposition of musical time. The shift itself was quite thorough, as even those commentators who attempted to treat the older notation on its own terms during the period frequently deny it any specific rigor. Related significations of this shift in paradigm as it centers on tempo are the use of "mood words" to indicate tempi, the use of dynamic markings, and the description of rubato.
In the previous article, I discussed the means by which tempo becomes a direct extension of rhythm in later medieval music. In earlier medieval music, the relationship is both closer and less clear, as there was indeed no regular rhythmic notation prior to the emergence of the Aquitaine polyphony. Even then, its scope was limited until the Ars Nova, leaving issues of tempo to mingle with those of rhythm and vice versa. Reading notation without current precision can lead to restrictive performances on that basis, but can also challenge our assumptions on semiology and performer involvement. The basic hierarchy of the rhythm-tempo complex was firmly established only with the white mensural notation, which resolved some contradictions in the Ars Nova system and was then abandoned in its strict relationships shortly afterward due to the reform of "tempo" as discussed above. The rhythm-tempo complex is encapsulated in Carnatic music by the single term laya, and so its interactions are more explicit despite a hierarchy of sorts. Although Indian music has an overarching tala scheme, actual musical phrases occur in different rhythms and with different displacements from the tala, allowing laya to be articulated via both smaller (phrase rhythm) and larger (tempo) interacting expressions against the formal tala as a structural baseline. In Carnatic music especially, the tala can function as a sort of mirror or focus through which smaller scale displacements are reflected in larger tempi relationships. A similar function may be appropriate for the "rhythmic modes" of Ars Antiqua polyphony.
In the Ars Antiqua cathedral music, a basic flexibility of line finds its complement in the tempo implications of architectural reverberations. In the absence of strict rhythm, this becomes a feedback relationship of sorts, with some sound combinations reverberating more strongly than others and consequently suggesting a variation in pace & nuance throughout the melodic line. For later medieval music, analogies between isorhythm and Indian tala are more directly applicable, and may be with respect to additive rhythms in other cultures as well. However, tempo implications of tala are not uniform, and in addition to the more nonlinear ramifications of Carnatic laya & syncopation as outlined above, one might also note the different approach of Hindustani khayal. There displacement on the main beat is approached less as a means to articulate larger structures than as an opportunity for increasingly animated activity in preparation for the end of the cycle, serving to underscore the linear construction of the tala as such. Of course, as Western notation changed and as bar lines became ubiquitous, rhythm became less about additive phrases and more about dividing units. The early use of bar lines as an aid to legibility gave way to more thorough rhythmic implications and then to the possibility of mechanical tempi connected to specific divisions of equal units. We have consequently returned, perhaps paradoxically, to a more mechanistic interpretation of time, buoyed by industrial schedules & timekeeping. The latter have been pervasive and make up one interesting & neglected area of social history, one with implications for the relevance of music and concomitant organization of time today.