Rhythm and expectation

Christopher Witulski

Part 2: Cycles of time Part 4: Consistent inconsistencies from Morocco

Part 3: Feeling the beat(s)

Just as musical repetitions and relationships can orient listeners over long stretches of time, smaller details impact how we feel music in the moment. Some of these details go unnoticed in common discussions of sound. For example, they may not appear in written music notation in western contexts. That doesn’t mean that they are not important or that we don’t feel them.

Much of the world’s music has a sense of pulse, a consistent sense of motion. This is one of many terms that is difficult to describe in words without falling back on other equally problematic sets of terminology. It also resists being bounded into a specific definition. Take dance: a pulse can be the points in time where you put your feet down or, in the case of Argentinean tango music, where you step while walking. Listen here and watch as the dancers’ feet move in a somewhat consistent pulse, or, to use another term, to a beat.

That word, beat, returns here. The pulse is often referred to as the beat, but I will nudge the meaning here to say that each pulse—each moment in time—is a beat. These beats that make up the pulse are not identical to the rhythm, though in Western music notation systems, they do get used to calculate larger structures like meter.

One striking aspect of the pulse and beats in a piece of music is that listeners can sense them, even if no sound happens at those moments in time. They are not explicitly aligned with strikes on a drum or chords on a guitar. They exist among and between sounds. They are perceived, imagined, and based on our expectations.

Listen to this rhythm. The consistent pulse is explicitly presented between the two instruments (a bass drum and snare drum). Try clapping the consistent pulse that is marked in blue boxes along with the rhythm.

In this case, every beat of the pulse (at least as I hear it) is played by one of the instruments. Here’s another example that’s similar. Try clapping along again. In this case, you can see the consistent pulse highlighted in blue outlines, but you can also feel it, even when the bass drum does not specifically articulate it. (Listen without the pulse, then you can use the button to add it in.)

This time, the beat in the middle of the repeating pattern is not articulated, but you may have still felt it and clapped during the space. Your body moves the same way and the clap feels appropriate there. This is the result of syncopation, an emphasized sound that does not appear on a regular beat or at an expected moment. In this case, the bass drum hit shows up before the expected beat.

As stated above, this is not just about drums. Here are some lines that could be in a funk band horn section. Even without the rest of a group, you may be able to feel the beat. They both have some syncopation, but the second one has even more. Yet, the pulse is still there (even if it’s harder to feel out of context).

Not all music has an underlying pulse. When a musician performs “freely” and without adherence to a consistent pulse, it can be termed free rhythm. This happens in solo introductions to a piece of music that showcases a performer’s virtuosic and expressive technique. Without an underlying consistent pulse, a musical idea can still toy with related ideas like pacing to generate motion and tension. By moving from slow to fast or suddenly shifting the momentum, free rhythm can generate a powerful feeling of rhythmic direction.

Grouping beats

Even when the pulse is fairly consistent, we don’t hear music as a steady stream of even sounds. It’s possible to intentionally give that sensation of mechanical consistency to listeners, but usually we hear and feel weight in different places as we find patterns by grouping beats together. These groupings comprise the concept of meter, though that term can be tied into music notation in ways that are not always helpful. Like so much else here, these are easier to hear or feel than they are to describe.

Most groupings are either sets that are multiples of two (duple) or three (triple). They can be combined to make innumerable other possibilities. They can also both happen at once. Most popular music is duple: rhythmic patterns like the ones described above overlay a pulse of evenly grouped beats. That does not mean that we all hear the same duple groupings: I might hear groups of 4 quick beats where you hear 2 slow ones. Unless you are trying to write music down, that distinction is unimportant. Here is a loop with a clave sound that divides the pulse in two different ways, but they are both duple.

Each group is called a measure or bar and where those measures start and end can be arbitrary. In the above example, someone could feal each iteration as one bar or made up of two shorter ones.

Triple groupings feel different. Here is an example from the American old time fiddling tradition as performed by Tommy Jarrell, an influential fiddle player. Try counting “one, two, three, one, two, three…” as he plays. A lifting or lilting sensation is at the core of many triple meter pieces, in part because of the dance steps that the music accompanies.

If the pace quickens, though, we might feel the central pulse somewhere else. In this short sample of an Irish jig, a patting sound marks the beat. Counting “one, two, three” quickly still fits well, but a dancer cannot move her feet at that speed. Instead, you step to a slower “one, two.”

“The Short Grass Jig” by Wendy MacIsaac, Jackie Dunn MacIsaac

We can also add sets of duple or triple groupings to make more complicated ones. Arabic music has a classical form called samaʿi that is technically ten beats. In practice, however, it is a group of three beats followed by a group of four (or two pairs), and then another group of three.

These groupings can appear in ways that foster ambiguity and generate tension for the listener. Rhythms can spread over time in a way that emphasizes two or more different pulses simultaneously. This displacement can be troubling or exciting. Stephen Friedson argues that it opens the body to an experience of trance (1996). Ann Danielsen describes how the guitar groove in James Brown’s famous song “Sex Machine” creates its own pulse that is slightly offset from the main one followed by the rest of the band (2006). While it does not bring about trance, it gives life to funk. In either case, a similar musical practice impacts the listener in a contextually-defined way, but both change our perception (Becker 2004).

Listen to this example and clap along to the pulse that you hear. Then try clapping to a different one by clicking the button. If you are up to the challenge, try shifting your perception from one to the other and back. At first, it might feel unnatural. Eventually, and with familiarity, it may get easier.

Dividing time

Just as beats are organized into larger groups (measures), they are divided into smaller parts. Of all of the rhythmic concepts discussed here, this might be the one where notational practices in western tradition struggles the most to depict the sounds that we hear. Sounds that land between beats rarely come at mathematically consistent intervals. Instead, a musician’s expressivity will push a note just before or after, making it subtly early or late.

The consistent division of beats that creates an expectation for listeners is called the subdivision. The nudges that happen in practice usually go unspoken, but some analysts and music theorists call it microtiming. Subdivisions are somewhat straightforward to talk about. Microtiming involves a level of nuance that can be far more difficult to articulate.

In western music theory practice, subdivision is generally taught as duple or triple, just like meter and measures (the larger grouping of beats). A duple subdivision divides each beat into two even halves or some other multiple of two (like four quarters). A triple subdivision divides them into three. Like the pulse itself, these divisions are not always made explicit in the music: they are structures we perceive as listeners.

The following examples present these structures as connected levels of organization. When listening, you can use the buttons to have the loop articulate different “scopes” (the measure/grouping of beats, the pulse/beats, and the subdivision/division of beats).

Note that since these are real audio examples, they don’t line up perfectly. The performers subtly shift their timing, even over a short period. The first example, which demonstrates a duple feel, is a version of “St. Louis Blues” by Jim Reese Europe’s “Hellfire Band.” Europe was a popular and successful black bandleader in the early 20th century who led a military band during World War I.

This second example, with beats grouped into sets of three and divided into duple subdivisions, is from American fiddle music.

Playing with subdivisions

In practice, musicians manipulate these divisions further. Swing is one common example that developed as part of the early jazz scene in the United States before the word came to represent its own genre of music. In swing, a duple subdivision turns into something else: the musicians lengthen the first half and shorten the second half. This means that they are no longer halves.

Musicians make use of the flexibility that live performance offers.1 Swing performers themselves vary the degree of their swing to create an individual style. Even within a single musical line, they change the ratios of their subdivisions to build and release tension (Benadon 2006). Christine Gerischer shares similar ideas about Brazilian samba music, showing that this is not unique to the genre known as “swing” (2006). These manipulations are examples of microtiming, adjusting the timing of notes in slight, but noticeable, ways.

These adjustments can sound and feel different. As a basic demonstration, move the slider to change the subdivision ratio and listen to how the simple swing drum set beat responds. Then, see if you can hear or feel the swing in Count Basie’s “One O’Clock Jump.” (It’s not always easy to hear, but you may feel like there’s some forward momentum that you can’t quite articulate. That’s fine! In fact, that’s the point!)

A frequent division of the beat that is related to swing involves a first “half” that is roughly two-thirds of the length of the beat, leaving one-third for the second “half.” This particular division turns into a mathematical triple subdivision where the first two thirds are linked together and roughly aligns with another name: a shuffle.

This example from Odetta, a folk singer and Civil Rights activist in the 1950s and 1960s, is a slow shuffle, which brings it closer to the sound of the blues.

This technique of rushing or delaying notes can happen anywhere in a piece of music, but it is a matter of balance. Breaking too far from expectations or norms could confuse a listener or dancer, but sticking to them methodically might get dull. One of my own favorite moments that exemplifies this is from a performance of “Watermelon Man” by Mongo Santamaria. While listening, try to let yourself feel the groove and, if the music inspires you, move along with it or clap. Then, feel how the percussion (drum set and other instruments) almost pull the horn section (the brass instruments and saxophone) along. It is even more extreme when the percussion drops out at about 30 seconds in. When I listen, I can’t help but to actually feel this tension in my body, as well as the relief that comes when they snap back together.

The final section turns to Morocco for a series of rhythms that challenge expectations by combining each of these practices.

Part 2: Cycles of time Part 4: Consistent inconsistencies from Morocco

  1. It should be said that flexibility in subdivisions and other expressive techniques are not exclusive to human performers. Electronic music has this capability and, in some cases, can do so with more specific intentionality on the part of the composer or producer.