A metronome that cuts the beat at the golden ratio, its inverse, and other constants. Two independent lines let you hear the polyrhythm; the pulse keeps you oriented.
The morph slider runs from an even 50/50 split to the exact constant. Along the way it passes through simple fractions: at 5/8 you are on a grid you can count, and at the far end you are on the irrational ratio. Learn the figure quantized, then peel it off the grid.
The readout under each line names the nearest grid and how many milliseconds you sit away from it. For 1/φ = 0.618 the closest is 8/13, but 5/8 = 0.625 is the one you can actually count, and at 64 bpm it lands about 7 ms off. So a golden division of the beat is a 5+3 over eight for every practical purpose. Go deeper and the figures walk down the Fibonacci numbers on their own: 13+8, then 8+5+8, then 5+3+5+8.
Slow tempos work best. Below 80 bpm the inner subdivisions stay distinct; much faster and a 0.236 segment turns to mush.