Music in Time - Pulse

Music in Time - Pulse

The Seven Liberal Arts

  • The original liberal arts consisted of seven areas of study divided into a lower division and an upper-division

  • The Trivium (lower division) consisted of Grammar, Logic, and Rhetoric

  • The Quadrivium (upper division) consisted of Arithmetic, Geometry, Music, and Astronomy

Number in….

  • The idea behind the upper-division was that students would learn: 

  • Arithmetic - pure number

  • Geometry - number in space

  • Music - number in time

  • Astronomy - number in space and time

Number in Time

  • How do we conceptualize time? 

  • How do we measure time? 

  • What are we measuring?

  • What is the basic unit of music? What is the unit of time?

PULSE

Before we define pulse in words, here is a simple visualization of what pulse sounds and looks like. Try tapping along with the center line.

Tap along with the center line once the visualization starts. Feel the steady pulse.

Definitions

1. Simple

  • A pulse is a simple sonic event that is repeated at regular intervals

  • Time is usually measured by counting pulses, e.g., seconds, minutes, hours, days, weeks, etc…

  • Digital metronomes and clocks are ideal generators of pulses (as long as we avoid any settings that provide accents)

  • Pulse is a basic element of music from around the world. It is not unique to Western music. 

  • Our notation system is not the most intuitive in representing the pulse. We will explore other possible representations. 

2. Neutral

  • There is no difference between one pulsation and another.

  • Any arrangement of beats at a higher level is excluded from the definition of the pulse.

  • Any accent (phenomenological or metric) is outside of the pulse itself.

3. Constant

  • The pulse is the only invariable element of a piece (or at least of each substantial section of a piece). 

  • In most musical traditions the pulse remains constant throughout a complete section of a piece (i.e., each movement, song, etc.)

  • The pulse is indifferent to other changes in the music (rhythmic, metric, tonal, etc.)

  • Any constant element in the piece is linearly related to the pulse. For example, if the pulse occurs every second and another element of the piece occurs every other second they are related by a factor of 2. 

  • Even when complex metric modulations occur, the pulse remains steady and constant, at least in some way. 

4. Intrinsic

  • The pulse is inherent in the music itself and specific to each piece: this makes it always a relevant factor. 

  • While a pulse can underly many different pieces, a piece cannot have two pulses at the same time. 

5. A Reference Unit

  • All temporal events (durations of notes, beginnings of notes, ends of notes) are perceived in relation to the pulse.  

  • In notated music, all temporal events are notated in relation to the pulse. 

6. Determining the Tempo

  • The pulse determines the tempo by setting the internal flow of the music it underlies.

  • This is easy to hear in the music of many traditions around the world (African Drumming, Blue Grass, Waltzes and Marches, to name a few).

  • In notated music, the length of notes is designated as the relation of the pulse to a minute (a universally accepted pulse in Western cultures). For example, quarter = 120 means that there are 120 notated quarters in the span of one minute. The quarter is linearly related to the minute.


To summarize, pulse is:

  1. Simple

  2. Neutral

  3. Constant

  4. Intrinsic

  5. A Reference Unit

  6. Determining the Tempo

Pulse is not

Outside of academic study, musicians often use terms like beat, pulse, meter, and rhythm interchangeably. That might work fine in informal settings, but when we analyze temporal structures in a rigorous way we need to separate these ideas clearly. Pulse is frequently mistaken for other concepts, so here is what pulse is not.

Pulse is not

  • Pulse is not Meter - Meter is not neutral, it is hierarchical. Meter is not constant (it often changes). Meter is not always simple. Meter is not intrinsic - meter is a notational aid and a tool we use to discuss music. It can also be a useful abstraction when composers create music. The meter does not determine the tempo. 

  • Pulse is not the beat - while the two terms can be used as synonyms in day-to-day conversation, they are not synonymous in the context of music theory, especially when we are discussing rhythm. Pulse is neutral and equal: every pulse is the same as every other pulse, and each pulse occurs at regular intervals. The beat, by contrast, is organized and weighted: beats can be strong or weak, and in some meters beats can have different durations (in a 7/8 bar, for example, one beat might last three eighth notes while another lasts two). When we listen to music, we hear pulse organized into beats - the beat emerges from pulse when we begin to perceive patterns of strong and weak, or group pulses into regular units. The beat takes its tempo from the pulse.

  • Pulse is not rhythm - rhythm is the general term that encompasses all temporal aspects of music - including the pulse and everything the pulse isn’t. 


Further reading: 

Arom, Simha, Martin Thom, Barbara Tuckett, Raymond Boyd, and György Ligeti. African Polyphony and Polyrhythm Musical Structure and Methodology. Cambridge: Cambridge University Press, 1991.