You may have heard of polyrhythms before. Perhaps you were at a concert one time and you heard some music nerds in the corner talking about “5 over 4” or “4 against 3” polyrhythms, and didn’t really think about what it was they were talking about. But, if you’ve arrived at this article, I’ve got good news for you, I am going to give a introductory lesson on polyrhythms, so the next time you encounter some music egg heads who wish to intimidate you with their speak, you’ll be able to dish right back at them.
Introduction
Before we get into the meat and potatoes, there are a few prerequisite terms that will help with understanding polyrhythms. Music, in countless ways is all about time; from interval ratios (notes) to time signatures and beats (rhythm) - you can’t escape it. Time is counted by use of numbers. Approaching rhythm as the counting of time, and dividing that time in different ways leads us into subdivisions. Subdivisions are what they sound like; ‘sub’ means of a smaller size, ‘division’ means to separate into parts, or the process of being separated. Put those two together and in the context of rhythm or beats and you have a good understanding of subdivisions; the division of beats into smaller parts.
Note values in standard notation - whole, half, quarter, eight, sixteenth (and so on) notes are in essence subdivisions of one another.
What’s important to realize is that different types of notes assume their own unique time duration. One whole note will take up the same time as 4 quarter notes, or 8 eighth notes, or 16 sixteenth notes (see the pattern?). So touching back on subdivisions, you could think of these notes as different ways of subdividing one measure.
Where things get interesting is when you overlay these subdivisions. Poly - meaning more than one - division is just that; the layering of different subdivisions.
4/3 Polyrhythm
Let’s start by examining a 4/3 polyrhythm. 4/3 polyrhythm means that during the same time 4 beats are being played 3 equally spaced beats will also be played. In standard notation, this could be a half note triplet over 4 eighth notes (figure 2).
**This is just one example of a 4/3 polyrhythm, you could have eighth note triplets over 16th notes or countless other options.
Often when we think too hard about polyrhythms they can seem more difficult than they really are. That is why certain mnemonic devices come in handy. The 4/3 polyrhythm can be made composite - simplified into one rhythmic idea - by the mnemonic “pass the golden butter”. The way the syllables lie within this phrase is a 4/3 polyrhythm.
I suggest if you aren’t familiar with this polyrhythm to look it up here, and say the phrase ‘pass the golden butter’ or ‘pass the goddamn butter’ (users choice) along with it. Once you get it, its like riding a bike; you can’t unlearn it (unless of course, you have some serious accident that renders you mentally unable).
5/4 Polyrhythm
The next polyrhythm I would like to look at is a 5/4 polyrhythm and another way we can think about polyrhythms. This one can be thought of as a quintuplet (5 - tuplet) over 4 eight notes (figure 3).
So just by looking at this, it’s a little difficult to be able to understand how exactly this one would sound. That is why I want to examine a different way of thinking about polyrhythms by using the lowest common multiple.
Lowest Common Multiple (LCM)
The method I would like to look at first has us find a lowest common multiple of the two numbers. 20 is the lowest common multiple of 5 and 4. From there we can set up a grid of the LCM. The grid can either be consisting of 5 rows of 4, or, 4 rows of 5. For this example, I will use a grid that is 4 rows of 5. Once we have our grid set, we then will italicize every 4th number in the repeating rows of 5.
1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
So, by accenting the 1’s of the rows we are accenting the repeating 5. By accenting the italicized numbers we are accenting the repeating 4. Accenting both the 4s and 5s is the 5/4 polyrhythm.
I suggest reading aloud the numbers and tapping out the accented beats; one hand will accent the repeating 4’s, the other hand the repeating 5s. After some practice you’ll be able to perform these polyrhythms with no problem.
And what is cool about this method, is that you can apply this to pretty much any other polyrhythm (within reason).
Determine the lowest common multiple.
Create a grid with numbered rows.
Accent the 1’s and other repeating number within the rows.
Gradually increase tempo.
Polyrhythm complete.
Thanks for reading! New articles out Sunday’s.
About the Author
Isaiah Grip is a 21 year old multi-instrumentalist composer (guitar, piano, violin, and voice) out of Longmont, Colorado who records and studies music independently under the name Tetra Veda, as well as collaborating with Ghostwrite Inc, and playing guitar in the progressive metal band Cloud Temple. His personal repertoire can be found on Bandcamp and YouTube under the name Tetra Veda.
Math and music, gotta love it.