Rock Perspectives

Groove Contraction

Creating Tension and Release

by Aaron Edgar

Groove contraction can create rhythmic tension and release. Similar to how, with implied metric modulation, we can use new subdivisions to trick listeners into feeling like the quarter-note pulse has shifted, we can use the concept of contraction to make tempos feel like they’ve changed. Unlike metric modulation, however, groove contraction modifies the subdivision while maintaining the original quarter-note pulse. 

Let’s start with an 8th-note-triplet pattern between the hi-hat and snare (Exercise 1). To create tension, we’ll insert another ghost note, which changes the pattern’s subdivision to 16th notes (Exercise 2). Employ quiet ghost notes and consistent hi-hat accents in both phrases. Using your metronome, transition back and forth between the following two exercises.

Creating Tension and Release 1

After you’ve mastered each hand pattern and can transition between the two, it’s time to expand them into actual grooves. To create a more dramatic effect, the bass drum and snare pattern in Exercises 3 and 4 were written to sound as similar to each other as possible.

Creating Tension and Release 2

Using these examples in a playing situation can depend on your musical setting. I like to treat the “tension” version—in this case Exercise 4—as a drum fill out of the original triplet groove. Try playing Exercise 3, and on every fourth or eighth bar, play Exercise 4 as a drum fill.

Next let’s apply diddles to this concept. In Exercise 5 we have a 16th-note funk groove composed of paradiddles between the hi-hat and snare. We’ll create our tension using paradiddle-diddles as 16th-note triplets. Alternate between these patterns, playing two bars each. Focus on your accents and bass drum placement—they’re meant to resemble each other.

Creating Tension and Release 3

Moving the second bass drum note in Exercise 6 to the “&” of beat 3 makes these previous two grooves sound closer to one another. However, its current placement is a closer match to the bass drum and hand-pattern interaction in Exercise 5. Combining this with the faster feel of the 16th-note triplets results in an intricate and twisted version of Example 5.

Let’s expand this concept further by creating similar feels within quintuplets and septuplets. We’ll use a RLRRL quintuplet sticking and a RLLRRLL septuplet sticking.

Creating Tension and Release 4

After you’ve worked through these grooves individually, its time to string them together. Transition through Exercises 5–8 in order of their subdivision, starting with 16th notes, then moving to quintuplets, 16th-note triplets, and finally septuplets. The tension increases with each new subdivision as more notes are jammed in between the similar accent pattern. When you get to the end, release the tension you’ve created by repeating back to the start.

Linear Patterns
We can also apply contraction to linear grooves. Here we’ll place less emphasis on keeping the grooves similar and instead focus on creating a longer phrase that goes through 16th-note triplets, septuplets, and 32nd notes, and then dramatically slows down with quintuplets before repeating back to 16th-note triplets. These 2/4 patterns employ a strong kick on beat 1 and an accented snare on beat 2.

Creating Tension and Release 5

Since the quintuplets and septuplets create the most tension, let’s use them as shorter transitions between the main 16th-note triplet and 32nd-note grooves. For this we’ll use a pair of six-measure phrases. The first phrase consists of four bars of Exercise 9 followed by two bars of Exercise 10. Our second phrase uses five bars of Exercise 11 and one bar of Exercise 12.

Creating Tension and Release 6

Taking It Further
These last two examples share a pattern that’s based on inverted doubles between the hi-hat and bass drum. In Exercise 14 we’re playing 16th notes in 5/4, and in Exercise 15 we modulate the same pattern into 4/4 using quintuplets. Each groove has a snare backbeat on beats 2 and 4, and there’s one additional snare to round out beat 5 in Exercise 14.

Creating Tension and Release 7

Exercises 14 and 15 also sound great between the bass drum and floor tom. Experiment with these patterns as well as the other grooves in this lesson. Writing your own patterns is a great method for working these concepts into your playing. You may not want to pull out this tool on every gig, but in an appropriate musical context, you can use it to create a range of subtle, powerful, and unique rhythmic statements.

Aaron Edgar plays with the Canadian prog-metal band Third Ion and is a session drummer, clinician, and author. He teaches weekly live lessons on You can find his book Boom!!, as well as information on how to sign up for private lessons, at