# Polyrhythms, Polymeters, and Irrational Rhythms...



## Randy (Feb 20, 2008)

Anybody have a definitive guide/way of dissecting the kinda rhythm they use in Meshuggah songs, etc. and writing partwork similarly? I'm a total noob to that aspect of writing so I was hoping someone could shine some light on the subject. 

Considering how common that kinda thing is on here, and a lot of ERG oriented music; a really great reference would probably make a great sticky. Thanks in advance! 

EDIT: All my searches have only turned up polyrhythms as far as multi-limb independent drumming and I'm guessing that's not exactly what I'm looking for.


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## ElRay (Feb 20, 2008)

Seems we're heading down a similar track, except I'm looking at it from a finger picking point of view.


levelhead86 said:


> All my searches have only turned up polyrhythms as far as multi-limb independent drumming and I'm guessing that's not exactly what I'm looking for.


Same here. I've started looking at this and seeing what I can extract. The first idea would be to look at simple two (or three) part polyrhythms and assign one part to each instrument (string or group of strings in my case) and use that as the rhythmic component. Then you could add what ever tonal aspects you'd like on top of the rhythm.

You could take something else from finger picking. Look-up Travis Picking and have one instrument play the "on beat" parts of a pattern and another instrument play the "off beat" parts. That wouldn't give you pure polyrhythms, but it would give a pulsing, quasi-syncopated feel.

You could also borrow a trick from Rush (I'm sure others have done this too). Bass and guitar would be playing alternating 6/8 and 7/8 while the drums were playing three bars of 3/4 and one of 4/4. Again giving a pulsing/surging feel.

Ray


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## Randy (Feb 20, 2008)

Thanks for the help! Hopefully we get a really great, indepth kind of guide out of this.



ElRay said:


> You could also borrow a trick from Rush (I'm sure others have done this too). Bass and guitar would be playing alternating 6/8 and 7/8 while the drums were playing three bars of 3/4 and one of 4/4. Again giving a pulsing/surging feel.
> 
> Ray



Yeah, that's the only polyrhythm stuff I'm at ALL familiar with/have experience with.

Or just simpler stuff, like alternating rhythm on one instrument and a straight beat underneath. But even with something like that, when I hear it on somebodyelses recording... it's uber-hard to dissect the time signature from the riff/passage.


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## Metal Ken (Feb 20, 2008)

ElRay said:


> You could also borrow a trick from Rush (I'm sure others have done this too). Bass and guitar would be playing alternating 6/8 and 7/8 while the drums were playing three bars of 3/4 and one of 4/4. Again giving a pulsing/surging feel.
> 
> Ray



Which song is this?


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## Uber Mega (Feb 20, 2008)

Read/Watch "Rhythmic Illusions", "Rhythmic Visions" etc. by Gavin Harrison (Porcupine Tree)...he's one of the leading guys in the world at this sort of stuff.


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## ElRay (Feb 20, 2008)

Metal Ken said:


> Which song is this?


IIRC Red Barchetta is one and they've done the same or something similar on others.

Ray


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## Desecrated (Feb 20, 2008)

http://www.sevenstring.org/forum/mu...s/42895-how-do-you-count-math-tech-metal.html

http://www.sevenstring.org/forum/mu...m-meter-music-meshuggah-27-pages-article.html


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## ElRay (Feb 20, 2008)

Uber Mega said:


> Read/Watch "Rhythmic Illusions", "Rhythmic Visions" etc. by Gavin Harrison ...


I have "Rhythmic Illusions", "Rhythmic Perspectives" and "Rhythmic Visions" in my Amazon.com Wish List, but haven't picked them up yet.

Ray


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## Uber Mega (Feb 20, 2008)

One of the most important things Gavin teaches is that, use Polyrhythms etc. to aid the music, don't just shove them in there because you want it to be uber tech. Anyone can make mathematical polymetrics, but making them sound musical is the hard part. He's the master at this, Porcupine Tree's new album doesn't hit you in the face as super technical, but subtlety under the surface the drums are fracking insane in places, they compliment the music perfectly.


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## stubhead (Feb 21, 2008)

There's another, somewhat separate idea called "rhythmic displacement" that bands like Meshuggah use a lot - it's more like a new starting point for one rhythm, that crawls though another rhythm. It can just be 3 over 4 or 4 over 3, as is explained in these examples:
Phrasing | Lessons @ Ultimate-Guitar.Com

However, it seems to me that this writer has oversimplified the concept of rhythmic displacement, because while it _contains_ those simple kinds of things, it also contains weirder stuff like this:
Welcome to Mel Bay's Bass Sessions® Web Magazine

The second example could actually be said to be in in 31/32 time, which the first writer says is ridiculous - and it is, if you _think_ of it the way he's thinking of it. However, if you see it as it's explained in the second example, the way my mind works it's actually _easier_ to get it.


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## Randy (Feb 21, 2008)

Desecrated said:


> http://www.sevenstring.org/forum/mu...m-meter-music-meshuggah-27-pages-article.html




Anybody able to rehost the PDF in this thread, by any chance?


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## ElRay (Feb 21, 2008)

Here's some collected other schtuff:
Under a (Philip) Glass Moon: Additive Process and Phrase Structure in Dream Theater&#8217;s &#8220;Constant Motion.&#8221;
A link where you can buy and download the article that Desacrated posted a while back: Re-casting Metal: Rhythm and Meter in the Music of Meshuggah by JONATHAN PIESLAK - Music Theory Spectrum - 29(2):219 - Abstract
And here's a page with MP3's of the referenced songs: Jon Pieslak » Re-casting Metal: Rhythm and Meter in the Music of Meshuggah
The Composition of Elliott Carter's Night Fantasies  -- a polyrhythm consisting of two streams of slow periodic pulsations ... forming a polyrhythm of 216:175

Ray


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## Desecrated (Feb 21, 2008)

YouSendIt - Send large files - transfer delivery - FTP Replacement

^^meshuggah article


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## Randy (Feb 21, 2008)

Desecrated said:


> YouSendIt - Send large files - transfer delivery - FTP Replacement
> 
> ^^meshuggah article



Success!


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## Durero (Feb 23, 2008)

Drew's post in this thread is excellent http://www.sevenstring.org/forum/music-theory-lessons-techniques/19294-poly-rhythms.html#post332506

Here's me basically saying the same thing in my own words...

I think the most fundamental concept is to be able to count & feel one beat while accenting groups of pulses which create the illusion of another beat happening at a different speed from the one you're counting.

The simplest example I know of is to count 3 beats of 8th note pulses and accenting every 3rd 8th note:

```
[SIZE="4"]accent: [B]1     &     1     &[/B]     ...
 count: [B]1[/B] & [B]2[/B] & [B]3[/B] & [B]1[/B] & [B]2[/B] & [B]3[/B] & ...[/SIZE]
```
This creates a ratio of 2 accents every 3 beats, or a 2:3 polyrhythm.


Grouping the 8th-note pulses into any odd number will create a polyrhythm effect. Here's 2:5

```
[SIZE="4"]accent: [B]1         &         1         &[/B]         ...
 count: [B]1[/B] & [B]2[/B] & [B]3[/B] & [B]4[/B] & [B]5[/B] & [B]1[/B] & [B]2[/B] & [B]3[/B] & [B]4[/B] & [B]5[/B] & ...[/SIZE]
```



The next easiest polyrhythms are based on triplet pulses.

Here's 2 beats of triplets with an accent on every 2nd triplet pulse which creates a 3:2 polyrhythm:

```
[SIZE="4"]accent: [B]1   a   &   1   a   &   [/B]...
 count: [B]1[/B] & a [B]2[/B] & a [B]1[/B] & a [B]2[/B] & a ...[/SIZE]
```


3:4

```
[SIZE="4"]accent: [B]1       &       a       1       &       a       [/B]...
 count: [B]1[/B] & a [B]2[/B] & a [B]3[/B] & a [B]4[/B] & a [B]1[/B] & a [B]2[/B] & a [B]3[/B] & a [B]4[/B] & a ...[/SIZE]
```



Then for 16th-note pulses any odd numbered grouping will do, with groups of 3 being most common. 

Here's a 4:3 polyrhythm:

```
[SIZE="4"]accent: [B]1     a     &     e     1     a     &     e     [/B]...
 count: [B]1[/B] e & a [B]2[/B] e & a [B]3[/B] e & a [B]1[/B] e & a [B]2[/B] e & a [B]3[/B] e & a ...[/SIZE]
```



So a general formula for polyrhythms is (and using the above 4:3 as an example): 

- choose any two numbers which cannot be divisible by each other (eg. 4 and 3)

- choose one number as the number of beats you'll be counting (eg. 3)

- the other number is the required number of pulses which you need to subdivide each beat with (eg. 4 subdivision pulses = 16th-notes)

- group the pulses into the same number as the number of beats (eg. accent every 3rd 16th-note pulse)


And voila you can make any polyrhythm ratio you desire.

For more challenging ones try 5:4, 7:3, etc.


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## ElRay (Feb 23, 2008)

Durero said:


> Drew's post in this thread is excellent http://www.sevenstring.org/forum/music-theory-lessons-techniques/19294-poly-rhythms.html#post332506
> 
> Here's me basically saying the same thing in my own words...
> 
> I think the most fundamental concept is to be able to count & feel one beat while accenting groups of pulses which create the illusion of another beat happening at a different speed from the one you're counting.


Another take on this is Adrian Legg's concept of "Vertical Slices":


[url=http://www.adrianlegg.com/tech_tidbits.htm]Adrian Legg Tech Tidbits[/url] said:


> {Originally posted in rec.music.makers.guitar.acoustic}
> If you look along a real or imaginary bar-line, vertical slices along it will give you everything that is happening in treble, bass and harmony at any beat or part-beat-you decide how fine you need the slices cut according to how simple or complex the material is. Then you learn one slice, followed by the next slice and so on, and learn the piece in terms of everything your hands are doing at any one point in time, rather than as separate horizontal treble/bass lines along the real or imaginary music or tab. The other trouble with horizontal lines is that there is usually information that is more to do with internal harmony or rythm than actual melody or bass lines.
> 
> Noted players have talked about an "independent thumb" - where the thumb theoretically goes off and boogies all on its own like an octopus tentacle while the others get on with the melody. Imho, what they are describing is a vertical slice based technique that has become sophisticated enough to give an _impression_ of thumb independence. I think it is confusing to introduce the idea of r.h. digits operating independently to people learning basic stuff. I know _hands_ are learned/practised separately on the piano, but I think this is probably a different kind of mental coordination issue. The grounds I have for thinking this way are empirical, so I could be completely wrong. But, academically right or wrong, it has worked ok for me so far, and seems to work ok for other folks.
> ...


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## Durero (Feb 24, 2008)

^ Awesome. I would totally agree with him.


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## All_¥our_Bass (Feb 24, 2008)

I just write two or three musical ideras in different time sigs and superimpose them on each other.


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## chaz1527 (Mar 6, 2008)

meshuggah uses metric modulation in their music. Its two or more different tempos (tempi) with a single point. if you decided to play 4 measures of 4/4 against 7/8 you would need to consider the equivalent value. since their is an 8th not difference you can conclude it would take 4 measures of 7/8 and another half measure left of 2/4 value left, which usually in meshuggah they usually will just play the last measure in four to sync it all together (orin this case 2/4). If you write it out you can just come up with your own patterns to play on the accents.


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