In the last lesson you learned about compound meter — time signatures where each beat naturally divides into three. But there's a way to combine the two:

Triplets.

A triplet is three evenly spaced notes played in the time that two notes would normally occupy. In 4/4, a quarter note normally divides into two eighth notes. An eighth-note triplet divides that same quarter note into three eighth notes instead.

Here are four straight eighth notes (two beats) followed by an eighth-note triplet (one beat) and a quarter note:

Notice the bracket and 3 above the triplet group — that's how triplets are marked in written music. The three triplet notes occupy the same space as two regular eighth notes.

Triplets aren't limited to eighth notes. You can have quarter-note triplets (three quarter notes in the space of two), sixteenth-note triplets (three sixteenths in the space of two), and so on. The concept is always the same: three in the space of two.

Triplets have a distinctive rolling feel. If you say "ONE and TWO and" you get the straight subdivision. If you say "ONE tri-plet TWO tri-plet" you get the triplet. Or try saying "straw-ber-ry, straw-ber-ry" — each "strawberry" is a triplet. There will be plenty of listening examples in the resources section.

You'll hear triplets everywhere once you start listening for them:

• Blues guitar solos are loaded with triplet figures
• The "da da DUM" opening of Beethoven's Fifth Symphony is a triplet rhythm
• Drum fills very often use triplets to build intensity

This one is much easier to get when you can hear the examples, so we'll keep it short and let you watch the linked videos. Essentially, swing rhythm is playing music that is notated (and counted) like straight eighth notes with a triplet feel. This is definitely a sound you've heard before.

In straight rhythm, eighth notes are evenly spaced: da da da da. In swing, they bounce: daa da daa da. The first eighth note is held a little longer, the second one is pushed a little later. It's the difference between walking and skipping.

Swing isn't usually written out with triplets and rests — that would be unreadable. Instead, the music is written with regular eighth notes and there's either a marking at the top that says "swing" or a little symbol showing straight eighths = triplet eighths. Or, in a lot of jazz and blues, it's just understood.

• Piano Lessons on the Web - How to Count and Play Triplets — Clear explanation with visual and audio examples.

• Synthet - music's most addictive rhythm - This video is a blast, lots of super fun triplet examples.

• Brad Harrison Music - How to Play Swing Rhythms — Great breakdown with real musical examples showing the whole spectrum from straight to heavy shuffle. He talks more about some of the other stylistic differences that often show up in Jazz music.

• 12tone - Tuplets — Fun little video about tuplets... triplets and beyond.

Need more?

• Wikipedia — Tuplet — Triplets are just one type of tuplet. This covers quintuplets, septuplets, and other groupings you probably don't need right now but might find interesting.

• Wikipedia — Swing (jazz performance style) — History and theory of swing feel.

Put on a blues or jazz track and listen for the swing. Then put on something in straight time (most pop or rock) and notice the difference. Try switching between them — count "1 and 2 and 3 and 4 and" with perfectly even spacing, then switch to "1 la li 2 la li 3 la li 4 la li" and feel the triplet underneath.

If you play an instrument, try playing a simple scale or melody with straight eighth notes, then play the same thing with a swing feel. It's the same notes — the rhythm is the only thing that changes, and it changes everything.