Tired of beats that repeat themselves every two measures?
Then you might want to check out PolyRhythms - a free iPad app designed to let you explore long, interlocking polyrhythmic sequences.
PolyRhythms has an unusual interface - two triangular rows of buttons, with each row of unique length. The lower left triangle controls "fast rhythms", while the upper right triangle controls events that occur more slowly.
Each of these rows of buttons controls a percussion sound. Tapping one of the buttons toggles the sound off/on for that step.
So far, pretty standard stuff for a drum sequencer.
What makes PolyRhythms unique is that, instead of rows of 16 steps, each row is of unique length. That means that, as the sequencer steps from left to right, each row ends and repeats itself at a different rate.
Here's how this works with the lower left triangle:
So, if you activitate the first button in the second and third rows, they play two against three, and instead of lining up every cycle, like a typical drum sequencer, they line up every 3 cycles.
As you can imagine, as you move on to longer sequence lengths, it takes longer and longer for the resulting patterns to repeat themselves. Using all the rows in the lower left triangle results in patterns that won't repeat for 840 beats.
The upper right triangle works similarly, except that it moves more slowly.
Each row of buttons in this triangle represents different subdivisions of the master loop. For example, the top-right row subdivides the top loop into 15 sections, while the bottom row of one button only plays once, at the very beginning of the 840 beat cycle.
Buttons along the top let you control save and load sessions, control playback and change the tempo.
PolyRhythms is an interesting app and it's free, so it's well worth your time to check it out. Its approach to drum programming is a refreshing change to standard 16-bar drum sequencing.
Unfortunately, though, PolyRhythms suffers from a problem common among current iPad apps - it leaves you wanting more.
A lot more.
Missing are the ability to sequence different rhythms to create songs, control over the sound assigned to each sequencer row, the option to load your own sounds and a way of synchronizing PolyRhythms with other devices.
PolyRhythms is an interesting start - but it needs to mature before it will become a serious music tool.
Pricing and Availability
PolyRhythms is available now as a free download for the iPad.