August 15, 2020

Are You a Rusher Or Are You a Dragger?

Ten years ago I was writing songs with irregular and compound meter. But math was messing with the groove. In 2018, I started substituting tempo changes in 4/4. Now the band grooves harder and expresses ideas more freely. The concept of a flexible musical grid was the breakthrough in getting theory and math out of the way of performance.

A flexible musical grid means using a specific tempo change to transform one time signature into another. It is basically stretching or compressing the musical grid without changing the sound. For example, 6/8 at 90 BPM transforms to 4/4 at 120 BPM, and 11/8 at 110 BPM transforms to 4/4 at 80 BPM. The transformation is done in 3 steps:

1. Convert the source and target time signatures to a common pulse
2. Divide the target beats per bar by the source
3. Multiply the source tempo by the quotient from step 2

Let's see how this works. First, 6/8 and 4/4 have a quarter note pulse in common by simplifying 6/8 to 3/4. Next, 4 is the target beats per bar. Divide 4 by the 3 beats per bar from the source time signature of 3/4. Finally, multiply the source tempo of 90 BPM by the quotient from step 2: 1.3 repeating. The tempo change in 4/4 is 120 BPM. Now rhythm can be written to sound the same in 4/4 as it did in 6/8. You can listen to "8 Out" to hear this concept applied.

Let's look at one more example. First, 11/8 and 4/4 have an eighth note pulse in common by using 8/8. Next, divide the target 8 beats per bar by the source of 11 beats per bar, resulting in .72 repeating. Finally, multiply the source tempo of 110 BPM by the quotient to get the tempo change in 4/4 of 80 BPM.

Playing musical phrases from any meter is easier in 4/4. This is another benefit of using a flexible musical grid. If you decide to try it, feel free to send me your questions / comments using the contact form.