Simple and Compound Meters Compared
In this lesson, you'll learn to move from a simple meter to its matching compound meter, and back again.
You've now met both families, so let's compare them. Every simple meter corresponds to a compound meter, and the other way around. Two corresponding meters always have the same number of beats:
- in the simple meter, each beat is filled by an undotted note value, so the beats are simple;
- in the corresponding compound meter, each beat is filled by the same note value, dotted, so the beats are compound.
Converting a meter
- To go from simple to compound, you add a dot to the note value that makes up one beat.
- To go from compound to simple, you remove the dot after each note value that makes up one beat.
Finding the matching time signature
To go from simple to compound, multiply the top number by 3 and the bottom number by 2. For example, 3/2 becomes 9/4.
To go from compound to simple, you do the opposite: divide the top number by 3 and the bottom number by 2. For example, 9/4 becomes 3/2.
To sum up, in simple meter the top number is always 2, 3 or 4, and in compound meter it is always 6, 9 or 12, for two, three and four beats in that order.
General comparison table
| Beats | Simple meter (beat divides by 2) | Compound meter (beat divides by 3) |
|---|---|---|
| 2 beats | 2/1 · 2/2 · 2/4 · 2/8 | 6/2 · 6/4 · 6/8 · 6/16 |
| 3 beats | 3/1 · 3/2 · 3/4 · 3/8 | 9/2 · 9/4 · 9/8 · 9/16 |
| 4 beats | 4/1 · 4/2 · 4/4 · 4/8 | 12/2 · 12/4 · 12/8 · 12/16 |
| Value of the beat | whole · half · quarter · eighth note | dotted whole · dotted half · dotted quarter · dotted eighth note |
Same length, different grouping: the hemiola
This point is subtle, so let's take our time. A measure of 6/8 and a measure of 3/4 contain the same number of eighth notes: six. But 6/8 groups them in two threes, which makes two compound beats, while 3/4 groups them in three twos, which makes three simple beats. Listen to how the stress changes:
- Meter
- 6/8: compound meter
- Beats per measure
- 2 beats
- Beat unit
- dotted quarter note
- Beat division
- triple: 3 eighth notes per beat
- Reading the numbers
- 6 = number of beat-thirds; 8 = the eighth note, one third of a beat
- Corresponding meter
- 2/4 (simple: top ÷3, bottom ÷2)
- Strong beats
- beat 1 strong, beat 2 weak
1. Write the compound meters that correspond to: 2/4, 3/8, 4/4, 2/2, 3/2. 2. Write the simple meters that correspond to: 6/8, 9/4, 12/16, 6/2, 12/8.
3. Turn this fragment in 3/4 into its corresponding compound meter by dotting each beat.