Click a beat to cycle it: accent → normal → silent. Spacebar starts and stops.
Two levels because they are two different sounds: the beat itself, and the subdivisions between beats.
The click drops out entirely — display included — then returns. If you drifted, you hear it land wrong.
No extra layers. Add one to hear a second pulse across the bar — 3 against 4, 5 against 4, and so on.
Row 2 is a shadow timer running the naive way. Row 3 is this engine. Let it run a minute — and note that jitter can spike hugely without row 3 moving at all.