PolyRhythm is just about the most straight forward app you can get. It is a metronome to help you get comfortable with cross-rhythms. That’s it. One screen. One sound. Multiple polyrhythms. Done!
It is one of those things that you might not necessarily need much but if you do need it this is a good tool. I have had solos before in cross-rhythm against the basic beat. A conductor is not going to change his pattern for just one person if the rest of the orchestra is using a different time signature so you have to know where your notes fit in.
This is the screen for PolyRhythm:
A definition from Wikipedia so that we are on the same page rhythmically speaking,
“Cross-rhythm refers to systemic polyrhythm. The New Harvard Dictionary of Music states that cross-rhythm is: “A rhythm in which the regular pattern of accents of the prevailing meter is contradicted by a conflicting pattern and not merely a momentary displacement that leaves the prevailing meter fundamentally unchallenged”
And one from Alex Ross The Rest Is Noise:
polyrhythm, polyrhythmic: Music is said to be polyrhythmic if two or more rhythms or meters are superimposed in a single passage, one pulling against the other(s). Masters of polyrhythm in the twentieth century include Stravinsky, Bartók, Conlon Nancarrow, György Ligeti, and Elliott Carter. In the “Procession of the Sage” from Stravinsky’s Rite, tubas play a sixteen-beat figure three times, horns play an eight-beat phrase six times, a guiro plays eight pulses to the bar, the timpani play twelve pulses to the bar, and so on:
(This is also the name of his book on 20th Century Music which I haven’t gotten to yet but it’s on my reading list.)
Here are some musical examples of cross-rhythm:
The Alex Ross definition refers to this part of the Rite of Spring:
Two against three from the opening of the Philip Glass piece Glassworks:
Although you can use PolyRhythm as a regular metronome, I wouldn’t use it for this purpose. The speeds are only available by 10’s and how slow and fast the metronome can go depends on the polyrhythm that you choose. Makes sense. Because not even the fastest drummer will be able to get up to 400 BPM with a polyrhythm of 11 against 4. (Before you tell me some inhuman percussionist who can do that, your ear couldn’t physically hear that clearly anyway so…doesn’t really matter.)
The polyrhythms go from 1 against 1, a regular metronome to 13 against 4.
I have been using this metronome just to hear the rhythms and then try to play them using my hands on my legs. There are drummers who can play multiple cross-rhythms at once. That just blows my mind. You can see a video of the developer of this app doing just that on his website.
PolyRhythm is available for 99¢ from the iTunes store for iPhone though it will work on iPad.
The developer is Wolfram Winkel at Five Over Three.
I have enjoyed exploring rhythmic possibilities with this app though it will probably not be in my everyday toolkit. It’s definitely worth giving it a listen and trying the rhythms out for yourself. I’m sure that I’ll be trying to use more of them in some compositions just to see what it can add to the piece.
And how about one more video that does a great job of showing you cross-rhythms: