Introduction: How to Understand Compound Time Signatures
Compound Time signatures are often found in our music. Anytime you see a time signature with an "8" as the bottom number, you have a compound time signature.
Remember that a Time Signature tells us how many beats are in each measure and what kind of note is going to get the beat that we're counting.
Compound time signatures share the same bottom number so that means we're counting 8th beats instead of quarter beats like we do when there's a 4 <---representing a quarter note - as the bottom number.
However, if you see in the 3 examples in the 1st image, the top numbers are all different.
This simply means that we're counting a different number of 8th beats for each measure in the music. We either count 6, 9, or 12 8th beats as indicated.
There's one more thing that is interesting about Compound Time signatures, and that is that we can count them more than one way.
We can either count the exact number of 8th beats for each measure as noted, or we can group the 8th beats together in sets of 3, and then count only 2, 3, or 4 quarter beats for each measure, depending on what our top number is.
In the 3rd image, I've drawn out the numbers for each separate note as well as drawing brackets over the 2 groups of 3 notes. Either way you end up counting this measure will be correct.
Let's see how this works for each different time signature. Once you understand how to count 6/8 either by single 8th beats or as 2 groups of 3 notes together, you'll be able to apply the same principle to the other remaining compound time signatures.
Step 1: 6/8 Time Signature
A 6/8 time signature is usually the first compound one that we learn and it's the most used in our music.
If you remember, we can count 6/8 one of two different ways, and both will be correct. (Which one you ultimately use will depend on the type of piece that you're playing and what tempo it is).
First, if we count every single 8th beat, we will count out each separate note with the corresponding verbal number.
- Try saying each beat 1-6 yourself, but say the beats slowly. Slower tempos work better when you want to count each beat individually. You want to put more emphasis on the very first note - almost like you were playing an accent on that note on the piano. Those accented beats are important in compound time signatures.
Next, say the first 3 beats as a group by putting more emphasis on "1"...then do the same with the last 3 beats and the emphasis this time will be on "4". Like this: "ONE, two three, FOUR, five six." The accent on beat four will be a little less than the one for beat one.
Lastly, change what you say to "1, 2, 3 - 2, 2, 3" or "ONE, two three, TWO, two three," to get used to thinking in terms of 2 counts/beats per measure instead of 8. When we play this together in the piano you'll see how I play these accents and how they help to divide the measure into different parts.
Now let's look at the 9/8 time signature...you'll find it easy to count if you're clear on how to count 6/8.
Step 2: 9/8 Time Signature
9/8 is just like 6/8, but we have either; three more 8th beats or 1 more grouped-together beat consisting of three 8th notes to make a total of 3, instead of just 2.
The individual 8th notes will be counted as before except we're going up through 9 here. Remember to put the accent on the 1st note only for this way of counting your notes.
Now when we group these nine 8th notes together into sets of 3, we'll have 3 sets, instead of 2 like we did with the 6/8 time signature. See that, in the 3rd image?
Count these 2 ways just the same way that you did for 6/8. First, do each individual note and then count the grouped 8th notes as; "ONE, two three, TWO, two three, THREE, two three'.
Can you figure out how many sets of 3 grouped 8th notes we'll have in a 12/8 time signature? Think about it... and then head to the next step.
Step 3: 12/8 Time Signature
You got it! We now have 4 beats of these grouped together 8th notes, instead of just 3.
Everything is the same with this 12/8 grouping as it was with the previous 2.
Count each one individually and slowly (or play that way if you're already at your piano), and count 1 - 12; with the accent at the beginning only.
When you're ready to group them together, practice saying: "ONE, two, three, TWO, two, three, THREE, two, three, FOUR, two, three."
The important thing to remember when we group the 8th notes together by 3, we need to accent the first 8th note of each group of 3, no matter how many beats we end up with, in the measure.
Sometimes, we have a compound time signature but the notes aren't written out as they are here in just simple straightforward 8th notes. They're mixed in with quarter notes and other rhythmic values that look really different. Let's look at an example of that in the next step.
Step 4: Counting Compounds With Other Rhythms
This example is based on a 12/8 time signature. So...we know that we have twelve 8th beats in the measure if we're counting each individual 8th beat.
But instead of having the individual beats written out, we have to find them within the note values on the page. It's harder to find the beats that you need to group together for your four sets of three 8th beats.
Figure out how many 8th beats are in each note, or pair the notes together so that their values together equal three 8th beats. This is what I've done in the 2nd image.
- A dotted quarter note = 3 - 8th beats. That dotted quarter note then gets one group of the set of three 8th beats.
- A quarter note has only two 8th beats in it so we need one more, which we find in the next note, an 8th note. There's the second group of 3. \
- The 3rd & 4th beats are grouped the same: an 8th note followed by a quarter note = three 8th beats. And here's where we get the 3rd and 4th set of beats.
Just figure out how many 8th beats will fit into each note, and then group them together by 3's, until you have 4 beats total.
Now let's get to the piano and learn how to play each of these compound time signatures on the keyboard.
Step 5: Come Practice With Me!
Make sure to "say" the counting described in this portion of the lesson just to get your feet wet with these compound time signatures. Counting out loud while playing them on the piano really helps too, so this is good preparation for that. Anytime you get confused while playing these, you can always go back to counting them verbally and feeling them that way, and then try them on your keyboard again.
I go through each of these time signatures in this video and give you plenty of examples to try yourself to help reinforce them. I think it's always helpful to hear and see the lesson as well as have it in writing.
You will enjoy learning compound time signatures and they are fun to add to your own compositions; don't be surprised if you feel like dancing when you do!