In this chapter, while we explain how to read the charts we'll also be explaining the basic concepts you need to know to start working your way through this book. If any of the concepts seem confusing at first, don't worry. They'll all become clearer as you begin using them in the coming lessons.
Because we're mainly interested in teaching the fundamentals of rhythmic structure, we're going to focus on just two variables of rhythm: 1) when sounds occur, and 2) what the sounds are. To notate these two variables, we use box charts instead of standard music notation because for our purposes they're simpler and clearer.
Here's what an empty chart looks like:
Pulses and subdivisions
The main function of the top row on a chart is to show how we're counting. But we also use the count row to show the pulse, which is indicated by shaded boxes (1 and 3 on the chart above). By "the pulse," we mean the underlying metronomic rhythm people feel in their bodies when music is played. Like your own pulse, it's made up of a series of regularly-spaced kinesthetic events called individual pulses. But unlike your own pulse, the pulse of a rhythm is a culturally-influenced, subjective phenomenon.
In African and Afro-Cuban music, the pulse is sometimes played on a drum or other percussion instrument. But often the pulse is silent, and – like a heartbeat – holds everything together without ever being heard. Because the pulse is so fundamental to rhythm, we present all the patterns in this book in relation to a pulse and have you tap the pulse in your feet while you play the patterns.
The time span between pulses can be divided into smaller units called subdivisions. The chart above has four pulses with four subdivisions each. Each individual subdivision – or beat – is an eighth note, which on our charts is represented by a single box. Any set of equal subdivisions forms a grid. Our charts use an eighth-note grid.
Whenever there's a symbol in a box beneath the count row, make a sound on that beat on your instrument:
When X is the only symbol on a chart, as in the chart above, play all the notes with the same sound, either a single note or a chord. When a chart contains both X's and O's, use one sound for X's and a second sound for O's:
Four and six
We say a pattern is in four when it can logically be represented on a chart with four pulses divided into four subdivisions each – like the charts above. Because each subdivision is an eighth note, pulses every four subdivisions fall on beats 1 and 3. In effect we're charting in cut-time, where a pulse falls on every half note and there are two half notes to a measure.
We chose to chart the patterns in four in cut-time because we find eighth notes easiest to work with. We could have used a quarter-note pulse divided into four sixteenth-note subdivisions. This would have made tracking the pulses easier because they would have fallen on every numbered beat instead of on beats 1 and 3.
But everything else would have been harder. Sixteenth notes are counted "one-ee-and-uh-two-ee-and-uh," and it's awkward talking about the "uh" of one or the "ee" of three. We also find a single 16-beat measure unwieldy compared to two 8-beat measures. Tradition played a role in our decision too; Afro-Cuban rhythms in four are usually charted and counted in cut-time. And if you count in eighth notes consistently in both four and six, you'll eventually be able to cross the border between them more freely.
We say a pattern is in six when it can logically be represented on a chart divided into two measures of six beats each, like the chart below. Each of the 12 subdivisions is an eighth note, and every eighth note is numbered. We're charting in 6/8 time, where there are 6 eighth notes to a measure (or 12/8, if you think of the two measures as one).
In six, we generally use four pulses with three subdivisions to a pulse. This puts the pulses on beats 1 and 4:
Timelines and cycles
Almost all rhythms are organized around a steady pulse. But African and Afro-Cuban rhythms are also organized around repeating rhythmic patterns called timelines. Unlike the symmetrical and often silent pulse, a timeline is an asymmetrical and always audible rhythm. All the musicians in a group use the timeline as a reference and play their parts in relation to it. That's what you'll be doing when you play the patterns in this book along with the CD.
In Afro-Cuban rhythms in four, the timeline is called the clave (klah-vay) and it's usually played on two cylindrical pieces of wood called claves
In Afro-Cuban rhythms in six and in most African rhythms, the timeline is usually played on a cowbell or other bell
Claves and bells are ideal for timelines because they produce crisp, penetrating sounds that can be heard above other instruments.
Sometimes, to make sure you know the relationship between a pattern and a timeline, we include a chart with the timeline (instead of the pulse) indicated on the count row with shaded circles:
The number of beats from the start of one repetition of a repeating pattern to the start of the next is the pattern's cycle. The cycle of the timeline is typically two measures long, and whenever we use the word "cycle" without further explanation, it's this cycle we're referring to.
The cycle of the timeline repeats for as long as a rhythm is played. So think of every chart as being written in a circle. When you get to the end go right back to the beginning and start over without missing a beat. When a pattern is longer than a single row, feel free to repeat any row or any set of rows as many times as you want before moving on.
We haven't put any tempo markings on our charts. Ultimately, the tempo of a rhythm will depend on your playing situation. The important thing for now is to play each pattern at a steady tempo and not to leave a pattern until it grooves.
We've done our best to make our charts as clear as possible. But no system of written notation can capture the nuances of a live rhythm. So while you're working your way through this book, be sure to supplement your study by listening to good music. If you're unfamiliar with the percussion music of Africa and Cuba and want to hear some spectacular examples, we've listed our favorite recordings at the back of the book.