Polymetric music is sometimes confused with polyrhythm, but the two are different. A polyrhythm is two pulse-rates inside the same bar (3 over 2, 5 over 4). A polymeter is two different bar-lengths happening simultaneously: one limb thinks the bar is 4 beats long, another thinks it's 5, and they only line up when the smallest common multiple of those bar lengths comes around. The hands continue to feel a 4-bar phrase; the kick — repeating in 5 — only completes its phrase every 5 hand-bars. Twenty 16ths to the resolution.
The metal application is everywhere from Meshuggah to Animals as Leaders to TesseracT. The riff is in 5; the drums are in 4; the listener feels both, and the music breathes in cycles longer than any single bar. The exercises below isolate the four most common metal polymeters: kick-in-5, kick-in-3 (the 3:4 dotted-quarter feel), kick-in-7, and a four-bar phrase that uses several at once.
- Each polymeter must be felt, not counted. If you're counting "1-2-3-4-5" on every kick rep you'll lose the 4 in the hands within two cycles. Instead: count the hands; let the kick feel like a metric ostinato that "comes back" every few bars.
- Practise each polymeter as a cycle: start at bar 1, play through the entire resolution period, and stop. Don't loop incomplete cycles — that's how you wire in confusion.
- Record yourself. The downbeat alignment at the end of the cycle is the audit. If kick 1 doesn't land with hand 1 at the resolution, the polymeter has gone wrong somewhere.
- Meshuggah — Catch Thirtythree. The whole album is one 47-minute polymetric study.
- Animals as Leaders — The Joy of Motion. Matt Garstka navigating dense polymetric riffs.
- King Crimson — Discipline. Bruford and Bill Bruford's textbook 7-against-4 in "Frame by Frame."