# Meters, polymeters, polyrhythms, compound meters. What are the differences?

Discussion in 'General Instruction [BG]' started by jamisonsalamand, Oct 19, 2010.

1. ### jamisonsalamand

Aug 15, 2008
I've read in a ton of places a lot of different definitions for a bunch of musical terms, so I'm trying to understand just exactly what they all mean.

I don't quite understand what meter is, but from what I've read it is a group of 2 or 3 notes. Places have stated that 4/4 is a meter, but I thought that was a time signature. Compound meter is also confusing. I've read that's it's something that can be divided by 3 like 9/8, and I've read elsewhere that it's a combination of 2 and 3 like 5/8. So in addition to not knowing what compound meter actually is, I'm also confused because some places seem to use meter and time signature interchangeably.

I also don't understand polyrhythms and polymeters. There is a drum beat that has a foot rhythm of three beats, that goes 4 & 1 with straight eights. Then the right hand plays three straight eighth notes that go 1 & 2. My drum teacher said that it's polyrhythmic, but my theory teacher said polyrhythmic is something like triplets on top of straight eighth notes.

Then there is a drum beat Danney Carey plays in a song I'm not sure of, playing hihat sixteenths with an open hit every third sixteenth note, over a kick and snare part in 4/4. So the right hand is 12/16 and the kick and snare are 4/4, and it lines up after four 4/4 bars. Some say this is polyrhythmic, some say it's polymetric. Also, what would it be called if there was a song with one instrument playing 5/4 while the other is in 4/4?

I'm confused about what these things actually are because I've seen so many definitions.

2. ### mambo4

Jun 9, 2006
Dallas
I may not be technically correct on all of this, but my understanding is this:

Meter: a catch-all term for all possible time signatures. anything that tells you how many beats to a bar. 4/4,2/4,6/8,3/4,12/8 are all kinds of Meter.

Compound meters : the top number is a multiple of 3.
3/4,6/8,12/8 are compound meters
wikipedia:says "subdivisions of the main beat (the upper number) are split into three, not two, equal parts, so that a dotted note (1.5 times longer) becomes the beat unit."

polymeter: different voices playing different meters that fall in and out of sync over several bars - your Danney Carey example.
my fav example is Sting's "St Augustine in Hell" with a hi-hat in 4/4 against a 7/8 bass riff.
usually expressed as a fraction against another fraction:" 3/4 against 5/8"

polyrhythms: different subdivisions squeezed into the same bar, never out of sync, always sharing the same downbeat on "1"
The classic Christmas tune "Carol of the bells" is an example of 2 against 3.
Traditional cuban rumba, and lots of west African drum rhythms use 6 against 4.
I don't understand the drum pattern you describe, but "[8th note]triplets against straight 8th notes" is a polyrhythm.
usually expressed as a number against another number (not fractions against fractions)

chances are Wikipedia will have audio examples of all of these

Jun 10, 2006
Halifax, Nova Scotia
I second what mambo said!

4. ### HooverBanned

Nov 2, 2007
New York City
re: polyrhythms versus polymeters

Another way to remember the difference is that in a polymeter the individual events (i.e., notes) tend to sound concurrently, and it is only their phrase lengths that are different. iow, the multiple simultaneous meters share the same subdivisions

...whereas in a polyrhythm it's the opposite; the individual events (i.e., notes) tend not to sound concurrently (except for downbeats), but the phrase lengths are the same.

5. ### TampabassSupporting Member

Feb 16, 2006
Tampa
I know you are, but what am I?
did somebody say George Porter, Jr.?

6. ### jamisonsalamand

Aug 15, 2008
Alright, I think I understand the difference of these terms now. Complex meter would be 5/8 then?

It is a beat similar to this, with all the notes the same kind(all normal eighth notes) but they each have a separate rhythm in different places.

So from my understanding, three eighth note triplets over two eighth notes is a polyrhythm, as well as a cross-rhythm. The above example is a polyrhythm, but not a cross-rhythm.

7. ### Richard Lindsey

Mar 25, 2000
SF Bay Area
I would say that's not a polyrhythm, because the subdivisions and the pulse are the same.

8. ### jamisonsalamand

Aug 15, 2008
I was suggested to go to wikipedia, and it says that that above example is a polyrhythm but not a cross-rhythm, and that this example is a cross-rhythm, which is a type of polyrhythm

Dunno how correct Wikipedia is

9. ### Richard Lindsey

Mar 25, 2000
SF Bay Area
I'm not sure that Wikipedia is really sufficiently clear on this point. Here's what they say:

Polyrhythm is the simultaneous sounding of two or more independent rhythms.
Polyrhythm [is] a general an nonspecific term for the simultaneous occurrence of two or more conflicting rhythms, of which cross-rhythm is a specific and definable subset.&#8212;Novotney (1998: 265)[2]
In my book, "independent" and "conflicting" are not the same thing at all, but if that's the textbook definition, OK.

I would say, though, that if the two rhythms merely have to be independent, not conflicting or crossing in any way, then the definition is a bit vague and may not accord that well with how the term is generally used, at least among most musicians I encounter.

Sometimes people use "polyrhythmic" to mean little more than "has a lot of percussion on it," but more often IME musicians use it to imply the possibility of hearing more than one pulse. For instance, there are ways of constructing grooves with measures of 12 8th notes where you might hear the meter either as 6/4 (six main beats) or as 12/8 (four main beats, or even as both simultaneously.

So whereas it may be true that this example is technically a polyrhythm, the more interesting examples, and the ones probably more people mean when they use the term, are likely to involve cross-rhythms to some degree.

Jun 9, 2006
Dallas
11. ### slybass3000Banned

Nov 5, 2004
LOL

Or James Demeter ?

12. ### champbassist

Apr 27, 2007
New Delhi, India.
13. ### HooverBanned

Nov 2, 2007
New York City

...except that he didn't really answer the question, and some of his insights, while not necessarily in & of themselves incorrect, suggest a definition that is incorrect as understood by academic musicians. To opine that his first definition (simultaneous time signatures that resolve after a certain number of beats) is a type of "polyrhythm" is a stretch at best. To imply that, for example, playing 7/8 against 4/4 (where the common 8th note subdivision is at the same tempo) is "basically the same thing" as triplet 8th notes against straight 8th notes is flat out wrong.

14. ### champbassist

Apr 27, 2007
New Delhi, India.
I think he provided a fair explanation of his opinion that neither is incorrect.

Mike Portnoy refers to different time signatures over each other on this youtube vid as polyrhythms (I do admit that he was probably not thinking of theoretical correctness in this vid, but it is an instructional, so I'd expect him to choose his words wisely). An, BTW, I was the guy providing the two definitions (user Leif Edling).

What the answerer mentioned there was:

Granted he didn't state that the two time signatures would at different tempos. That is why I said 'a fairly satisfactory answer' and not 'an admirable perfect answer'

So, while
is incorrect in the specific terms that 7/8 against 4/4 isn't translatable into triplets, if you do consider the guy's statement regarding two overlaid time signatures, the connotation between tuplets and time signatures isn't wrong, either.

Also, I'd like to know what your views are regarding polymeters and polyrhythms. I'd think you're probably siding with mambo4's definition above. Personally, even I think that it's a nice, uncluttered way of dealing with these terms. Thus, in the Wikipedia page, my first definition would denote a polymeter, while the second one would denote a polyrhythm.

15. ### HooverBanned

Nov 2, 2007
New York City

Right; see my post#4 above for the Cliff Notes version.

The reason I take issue with this statement

is specifically because it doesn't address the implied tempo difference inherent in tuplets. That is the fundamental difference between a polyrhythm & a polymeter: how quickly (either absolutely or relatively) the multiple subdivisions are moving. So it's not "a fractal of [the] first definition", it's an explicit iteration of the second definition, and the second definition only.

16. ### champbassist

Apr 27, 2007
New Delhi, India.
That's exactly what I mentioned in my post, as well. Actually, it appears that the answerer was probably trying to consciously make his point as to why both definitions are basically same.

As I said, the definitions of polymeter and polyrhythm that you 'support' are the ones I, too, think work best. But can you provide some references wherein these differences have been explicitly stated? It will provide support for any further debates on this topic.

17. ### HooverBanned

Nov 2, 2007
New York City
Well, it would be more credible if I could supply some actual academic peer-reviewed reference books, since -- as you've already discovered -- you can find something on the internet that supports nearly any position!

quite concisely and almost verbatim supports my understanding of the difference between polymeter & polyrhythm...but who the heck is "ultimate-guitar.com" and why should anyone believe them?)

Sadly, there are no academic peer-reviewed reference books here at the studio, so this may have to wait until I go home this weekend. However, off the top of my head, I would suggest consulting
- The Grove Dictionary of Music and Musicians
- The New Harvard Dictionary of Music
- The Rhythmic Structure of Music (Grosvenor Cooper & Leonard Meyer)
- Shaping Time (David Epstein)

fwiw -- and I realize this could just come across as bragging and/or name-dropping, but I figured I'd offer it up anyway -- my understanding of these concepts comes by way of my two college degrees; specifically, polyrhythms in Larry Bethune's undergraduate course "Rhythmic Ear Training" at the Berklee College of Music, and polymeters in Tom Pollard's graduate course on "Rhythmic Resolution" (that wasn't the actual name of the course, just the most pervasive concept I can recall from it) at the New England Conservatory of Music. I also attended master composition classes with Milton Babbitt and Elliott Carter while I was getting my master's degree at NEC, and both esteemed gents spoke of polyrhythms & polymeters in ways that corresponded to my understanding of these ideas.

(Likewise, who the heck am I and why should anyone believe me?)

A good library is still the best resource for this sort of thing.

18. ### champbassist

Apr 27, 2007
New Delhi, India.
So I got hold of the definitions of 'polymetric' and 'polyrhythm' in the Harvard Dictionary Of Music (the old 2nd edition, though).

The entry for the word 'polymetric' states that:

Moreover, both the definitions that we have been talking of (one being for polymeter and the other for polyrhythm) are referenced under the entry for 'polyrhythm'. It is stated that:

While these definitions definitely affirm our terminology as being correct, the distinction is not as well marked as I would like, I dare say.

I wonder if this particular definition has undergone any changes in recent editions. Would be nice if you could check it out.