Beat detection via amplitude threshold fires a visual event when RMS crosses a set level

A simple beat detector watches the rolling RMS amplitude and fires a trigger whenever it rises above a threshold. This captures kick drums and loud transients as discrete events rather than continuous values — enabling event-driven visual responses (flash, spawn, color shift) rather than continuous parameter scaling. The threshold must be tuned per track: too low gives false triggers on every note, too high misses soft beats. Because a fixed threshold is fragile, practical detectors add hysteresis (see adaptive beat detection). More robust approaches watch a specific FFT frequency band (bass) instead of broadband amplitude.

Examples

Track getLevel() each frame; if (level > beatThreshold) onBeat(). The workshop’s ‘Amplitude Threshold’ and ‘Simple Beat Detection’ demos isolate this pattern.

Assessment

Write pseudocode for a threshold beat detector using p5.Amplitude; name one limitation of a fixed broadband threshold that per-band FFT detection solves.