Generating Polyrhythms

Hi. Polyrhythms are two or more rhythms occurring simultaneously and are often used effectively in both improvisation and composition. A knowledge of polyrhythms can be of great benefit in both expanding your vocabulary and to improve your time.

In this lesson I'd like to share a method to generate polyrhythms. To do this I will show how to derive a polyrhythm of 3 over 2; a polyrhythm with which many of us would be familiar; if you can play 1/4 note triplets over 1/4 notes, you know how this polyrhythm should sound.

By following these steps, you will find it easy to generate common polyrhythms such as 2 over 3, 4 over 3, 4 over 5 and 4 over 7 etc. You can use this method to generate more obscure polyrhythms such as 5 over 4 or 7 over 5 etc, but in order to do this, you need to be well versed in the accurate articulation of Quintuplet and Septuplet rhythms.

Example: 3 over 2.

AIM: To play three evenly spaced beats in the same time as two.


Start with our base rhythm (2).


Now divide each beat evenly into our upper rhythm (3).


Note we have six even beats in the time of our original two. But we're aiming to get three even beats in the space of two. So we need work out how many times three divides into six; 6 ÷ 3 = 2
So we must accent every second beat to gives us the "three pulse" of the three over two polyrhythm. That is, the first of every two beats gives us the polyrhythm of three over two.


By only playing the accents we have achieved a three over two polyrhythm.

This concept can be employed to generate any polyrhythmic pulse. This particular one is quite easy, as it is based on an eighth note triplet subdivision, which is a common rhythm in western music. As you become more familiar with triplet based polyrhythms, try generating more exotic rhythms based on quintuplets and septuplets.

As I said at the top, a knowledge of polyrhythms can be of great benefit in both expanding your vocabulary and to improve your time. If you don't feel the need or desire to employ these kinds of phrases when you play, you will still derive much benefit from studying them; for one thing you will improve your own time simply by dealing in the relationships of the rhythms to the underlying pulse. Also, to understand and appreciate how these rhythms relate to each other, helps in relating to other players within an ensemble. If you do choose to use these rhythms when you play with other musicians, try to use them musically to create tension and release. Good luck and have fun!