Gangly Chords

Earlier in this chapter, we discussed how footsteps and gangly bangs ring, and how these rings tend to have pitches. I hinted then that it is the Doppler shifting of these pitches that is the source of melody, something we will get to soon in this chapter. But we have yet to talk about the other principal role of pitch in music–harmony and chords.

When pitches combine in close temporal proximity, the result is a distinct kind of musical sound called the chord. For example, C, E, and G pitches combine to make the C major chord. Where do chords fit within the music‑is‑movement theory? To begin to see what aspect of human movement chords might echo, consider what happens when a pianist wants to get a rhythm going. He or she could just start tapping the rhythm on the wood of the piano top, but what the pianist actually does is play the rhythm via the piano keys. The rhythm is implemented with pitches. And furthermore, the pianist doesn’t just bang out the rhythm with any old pitches. Instead, the pianist picks a chord in which to establish the rhythm and beat. What the pianist is doing is analogous to what a guitarist does with a strum. Strums, whether on a guitar or a piano, are both rhythm and chord.

My suspicion is that rhythm and chords are two distinct kinds of information that come from the gangly banging sounds of human movers. I have suggested in this chapter that rhythm comes from the temporal pattern of human banging ganglies. And now I am suggesting that chords come from the combinations (or perhaps the constituents) of pitches that occur among the banging gangly rings. Gait sounds have temporal patterns and pitch patterns, and these underlie rhythm and chords, respectively. And these two auditory facets of gait are informative in different ways, but both broadly within the realm of “attitude” or “mood” or “intention,” as opposed to being informative about the direction or distance of the mover–topics that will come up later in regard to melody and loudness, respectively.

If rhythm and chords are each aspects of the sounds of our ganglies, then we should expect chords to cycle through their pitches on a time scale similar to that of the rhythm, and time‑locked to the rhythm; the rhythm and chord should have the same time signature. For example, in an Alberti chord/rhythm pattern, one’s left hand on the piano might play the notes [C GE G][C GE G][C GE G], where each set of square brackets shows a two‑beat interval, and bold type and underlines indicate the emphases in the rhythm. One can see that the same two‑beat pitch pattern and rhythm repeats over and over again. The pitch sequence and the rhythm have the same 2/4 time signature. It is much rarer to find chords expressed in a way that mismatches the rhythm, such as the following case, where the chord is expressed as a repeated pattern of three pitches–C‑G‑E–and thus the two‑beat rhythm cycles look like [C GE C][G EC G][E CG E]. In this case, notice that the first two‑beat interval–the rhythm’s cycle–has the pitch sequence CGEC, but that the second one has, instead, GECG. The pitch cycle for the chord is not matched to the rhythm’s cycle. In real music, if the rhythm is in 2/4 time, then the chord will typically not express itself in ¾ time. Rhythm and chords tend to be locked together in a way that suggests they are coming from the same worldly source, and therefore the arguments in this chapter lead one to speculate that both rhythm and chords come from, or are about, our gangly banging sounds.

We can also ask which pitch within the expressed chord is most likely to be the one played on the beat. For human movers, the lowest‑pitched gangly bang we make is usually our footsteps. For music and the rhythmic expression of chords, then, we expect that the pitch played on the beat will tend to be lower than that played between the beats. Indeed, chords are usually caressed starting on the lowest expressed pitch (and often on the chord’s tonic, which in a C major chord would be the C pitch). Chords are, again, like gangly rings, with the lowest pitch ringing on the beat.

Consider yet another attribute of human gait: our gangly bangings can occur simultaneously . Multiple parts of a mover’s body can be clattering at the same time, and even a single bang will cause a ring on both the banger and the banged. So we should expect that the auditory mechanisms evolved for sensing gait would be able to process gait from the input of multiple simultaneous pitches. Consistent with this, the pitches within a chord are commonly played simultaneously, and our brains can make perfect sense of the simultaneously occurring notes. Pitch modulations that are part of the melody, on the other hand, almost never occur simultaneously (as we will discuss later).

The idea that musical chords have their foundation in the pitch combinations heard in the banging gangly sounds of human movers is worth investigating further. However, there are a wide variety of phenomena concerning chords that one would hope to explain, and that I currently have no theoretical insights into how to explain based on the raw materials of our ganglies. The laboratory of Dale Purves at Duke University has carried out exciting research suggesting that the human voice may explain the signature properties of the diatonic scale, and one might imagine persuasive explanations for chords emerging from his work. In fact, people do often vocalize while they move and carry out behaviors, and one possibility is that chords are not about gangly bangs at all, but about the quality of our vocalizations. The advantage of looking to gangly bangs as the foundation for chords, however, is that banging ganglies are time‑locked to footsteps, and thus intrinsically note‑like. Human vocalizations, however, are not time‑locked to our footsteps, and also lack a clear connection to the between‑steps movements of our banging ganglies. If chords were driven by vocalizations, we would not be able to explain why chords are so wedded to the rhythm, as demonstrated above. If one can find chords in our ganglies, then it allows for a unified account: our banging ganglies would explain both rhythm and chords–and the tight fit between them.

Chords, I have suggested, may have their origins in the pitches of the complex rings given off by gangly human movers. Later in the chapter, I will suggest that the pitch modulations in melody, in contrast, come from the Doppler shifting of the envelope of those gangly pitches.