12/8 Time Signature: How to Count It, Why It Is the Blues Meter, and a Click to Practise With

What 12/8 time means

Twelve eighth notes fill the bar and twelve divides into four threes, so the real beat is the dotted quarter note and there are four of them. That makes 12/8 compound quadruple: four beats (quadruple), each dividing in three (compound). It is 4/4 with a triplet built into every beat, which is why so much 12/8 music is written as 4/4 with a shuffle or triplet feel marking instead; the two notations describe the same thing, and 12/8 is simply the one that writes the subdivision into the time signature.

It is also two bars of 6/8 stitched together. The difference between 6/8 and 12/8 is where the strongest accent falls: every two beats or every four. A slow blues could be written in either; 12/8 is chosen because the four-beat bar matches the four-beat phrasing of the twelve-bar form.

How to count 12/8

Count in four: ONE and a TWO and a THREE and a FOUR and a, accents on pulses 1, 4, 7 and 10, with 1 the strongest. This is the feel at any real tempo.

While learning: count all twelve, ONE two three FOUR five six SEVEN eight nine TEN eleven twelve, to keep the triplet inside each beat even. Then drop back to four.

A slow blues drummer plays the four big beats on the snare and hi-hat and lets the triplet ride underneath; the three-against-the-beat swing is the entire style.

What 12/8 feels like

12/8 sways. Four beats give it the solid, walkable frame of 4/4, and the triplet inside each beat gives it a roll that straight 4/4 does not have. Slow, it is the swaying weight of a blues ballad; medium, it is a shuffle; fast, it is a driving gospel or rock-and-roll groove. The style lives in how hard the third pulse of each beat leans into the next beat.

Songs and pieces in 12/8

• Since I've Been Loving You (Led Zeppelin): a slow blues in 12/8, the drums rolling the triplet under every beat.
• Unchained Melody (The Righteous Brothers): the classic 12/8 ballad, the piano arpeggios spelling out the four rolling beats.
• Earth Angel (The Penguins): doo-wop in 12/8, the template for a thousand slow-dance songs.
• Slow blues, generally (the whole idiom): most slow twelve-bar blues is felt in 12/8 whether it is written that way or as 4/4 with a triplet feel.

How to practise 12/8 with a metronome

Play the four, feel the three. Tap the four accented pulses (1, 4, 7, 10) with the click until the bar feels like a slow 4/4, then let the triplet subdivision back in. The style is in the roll, but the frame is four.

Practise the shuffle honestly. In 12/8 a shuffle is the first and third pulse of each beat. Play only those against the tool's click and make sure the third pulse lands late, on the last triplet, not halfway between beats; that is the difference between a shuffle and straight eighths.

Slow it down to hear the triplets. The tool's BPM is the eighth-note pulse, so a slow blues at 50 big beats a minute is 150 on the tool. Start nearer 100, where every pulse is audible and the triplet cannot hide, and work up from there.

For the theory behind why the bottom number never changes a meter's class, and how simple, compound and odd meters relate, see Time Signatures Explained. For any meter not covered here, the odd meter metronome plays anything from 1 to 16 beats with its natural grouping.

Questions about 12/8