Say I have six groupings of eighth note triplets, 18 total notes. I want to play 16 eighth note triplets, leave off the last two notes ("partial triplet"), and repeat the section.

To my ear, that's 4/4 and 2/4, but of course 4 eighth note triplets does not add up to 2/4:

Image of 4/4 and partial 2/4 measure

What time signature should the second measure be (or how should I change the notation? When I play the above in Guitar Pro, it sounds right, but the second measure lasts too long.

I play mostly by ear, and I am struggling to understand irregular time signatures and reasonably transcribe what I'm playing.

  • if the problem exists throu out the piece it's probably 3/2 times (or 3/4 with 16th triples) Commented Dec 6, 2021 at 9:49
  • 2
    Ironically, I commonly see passages with the 3-3-3-3-2-2 rhythmic pattern notated in 4/4 time.
    – Dekkadeci
    Commented Dec 6, 2021 at 15:30
  • Are you certain that the last note is as long as the preceding 15 notes, and that there are no rests anywhere? It's unusual to have two accented notes of the same length immediately adjacent to each other as you have here at the repeat. Can you post an audio file of this rhythm, including the repeat at least once? To put it another way, what you have here is roughly equivalent to five measures of 3/8 and one measure of 1/8. A time signature of 1/anything is weird and could be a red flag hinting at some other error of transcription.
    – phoog
    Commented Dec 6, 2021 at 15:30
  • 1
    Both answers give good but very different solutions. To really answer the question you need to show what the other parts are playing.
    – PiedPiper
    Commented Dec 6, 2021 at 19:48
  • I'd say the last bar is an "irrational" measure of 4/12.
    – QBrute
    Commented Dec 7, 2021 at 10:20

2 Answers 2


Where are the accents, and is this meant to be a polyrhythm?

You have 16 actual notes in your sample notation. That would fit into 4/4 time with the groupings of three forming a polyrhythm. This kind of pattern comes up in rock music...

enter image description here

...something like this seems more common, but follows the same polyrhythm idea...

enter image description here

...actually, that's kind of a ragtime rhythm.

Or like this to carry the polyrhythm over the bar line...

enter image description here

I gave the polyrhythm example using two parts, but you can imply something similar with one part. The important point is to put your brief example into context. If your example changes grouping to threes within an otherwise grouping of fours, you could notate it either with or without time signature changes...

enter image description here

If the main feel is 4/4, then I think the first option is better.

We can't really say what is best without the complete picture of what you are doing. Generally, a meter should pervade through out the whole piece or at least for significant sections. Momentary deviations from the meter will be handled with notation other than a time signature change. For example, for a piece in 3/4, instead of this meter change...

enter image description here

...a tie would be common...

enter image description here

If the feel of groups of 3 and 4 pervades most bars, and you really have an irregular meter, another option is to use additive meter. I think you would use that for your pattern, like this...

enter image description here

...I think technically you are supposed to make the top part of the time signature match the beam groupings using 3 and 2, but 3+3+3+3+2+2 for the top part seems like overkill.

enter image description here

  • 3
    This is a better answer since it raises the crucial point that the correct notation of the passage depends on the rhythm one is trying to express in the notation. More than one solution might be correct, of course, and an irregular compound meter would be more reasonable if the piece is for an unaccompanied solo instrument or for an ensemble playing homorhythmically. This approach would also be reasonable in that case, however, and is preferable if some instrument (or a pianist's left hand) is playing a "straight" counterrhythm as in the examples given here.
    – phoog
    Commented Dec 6, 2021 at 16:08
  • I wonder whether the second example might be better if the r.h. notes in the first beat of the second measure were d b g d instead of b g d b. Did you consider that, and, if so, why didn't you do it that way? I wonder whether I'm missing something here.
    – phoog
    Commented Dec 6, 2021 at 16:10
  • @Phoog it seems like 3+3+2 is a common pattern, that's why my second example is just really one bar, but I added a third example along the lines you suggested, which is more like the OP's two bar length. Commented Dec 6, 2021 at 17:52
  • @MichaelCurtis: Another notable, exemplified by Journey's "Faithfully" is "2+3+3 | 3+3+2", which makes the concatenation of four consecutive threes noticeable, but doesn't split any of them across a bar line.
    – supercat
    Commented Dec 7, 2021 at 16:37
  • The first example you provided seems like the best way to represent the musical idea. I was fixated on the triplet feel of it, but underneath I think it's just 4/4 with slightly weird-sounding groupings. And using accents to get the triplet feel across is a great tip!
    Commented Dec 7, 2021 at 20:16

You can notate the measure as (1-1/3)/4, but the better solution would be to notate the first measure as 12/8 and the second as 4/8. 12/8 is understood by convention as 4 groups of three eighth notes.

Another option would be to triple the tempo and change the first measure into four measures of 3/4 and the second measure into a measure of 4/4 (or 3/4 and 1/4, which might be more accurate according to what you're trying to achieve).

  • Thank you. That makes sense. I tried that earlier, but somehow convinced myself it was wrong.
    Commented Dec 5, 2021 at 22:41
  • Why not four measures of 3/8 instead of 3/4?
    – phoog
    Commented Dec 6, 2021 at 15:34
  • @phoog No special reason. The only difference in this case would be notational. The important detail is the change in tempo.
    – Aaron
    Commented Dec 6, 2021 at 15:52
  • 1
    Changing tempo to notate rhythm is a terrible idea. It may work in a DAW, but for a human performer it would be extremely confusing: you request changing tempo, but in fact you want them to play in the same tempo you just fail to notate it right. 12/8 + 4/8 seems OK, but I think Michael Curtis suggested a much more likely interpretation. Commented Dec 6, 2021 at 16:01

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.