Random Metronome Accent Pattern Generator
Generate one measure of beat and subdivision onsets with a fixed downbeat and bounded random accent levels.
Description
Generate one measure of evenly spaced metronome events with a fixed downbeat and random accent levels.
A metronome establishes a steady pulse, while subdivisions add ticks between beats. Accents can help distinguish the measure’s downbeat from its other events.1
This generator returns result.durationMilliseconds and result.events. Each event has beat and subdivision numbers, onsetMilliseconds relative to the measure start, and a unitless accent value. It generates event data rather than clicks, MIDI, or audio.
beatsPerMinute defines the chosen beat unit; beatsPerMeasure counts those beats. No time-signature denominator is supplied, so a quarter-note or other beat interpretation must come from your musical context.
When to use Random Metronome Accent Pattern Generator
Use it for one-measure timing fixtures or a randomized accent pattern that another application will play or display.
How to use Random Metronome Accent Pattern Generator and understand its results
- Enter finite beatsPerMinute of at least one, integer beatsPerMeasure from 2 through 16, and integer subdivisions from 1 through 8.
- Run and read result.events in onset order. Beat and subdivision labels begin at one; onset zero is the start of the measure.
- Map the unitless accents to your playback or display convention separately. Repeat the pattern using durationMilliseconds as its measure period if looping is intended.
beat duration = 60000/BPM; step = beat duration/subdivisions; onset = (beatIndex × subdivisions + subdivisionIndex) × step Zero-based internal indices produce beatsPerMeasure × subdivisions events. Duration is beatsPerMeasure × beat duration.
first accent = 1; other accents = 0.25 + 0.5 × randomDraw Timing is fixed by the tempo and subdivisions; randomness changes accents, not event positions.
The BPM-to-milliseconds calculator supplies beat duration. One random draw is consumed and validated for every event, including the first event whose accent is always one.
{
"input": {
"beatsPerMinute": 120,
"beatsPerMeasure": 4,
"subdivisions": 2
},
"randomDraw": 0.25,
"output": {
"result": {
"durationMilliseconds": 2000,
"events": [
{
"accent": 1,
"beat": 1,
"onsetMilliseconds": 0,
"subdivision": 1
},
{
"accent": 0.375,
"beat": 1,
"onsetMilliseconds": 250,
"subdivision": 2
},
{
"accent": 0.375,
"beat": 2,
"onsetMilliseconds": 500,
"subdivision": 1
},
{
"accent": 0.375,
"beat": 2,
"onsetMilliseconds": 750,
"subdivision": 2
},
{
"accent": 0.375,
"beat": 3,
"onsetMilliseconds": 1000,
"subdivision": 1
},
{
"accent": 0.375,
"beat": 3,
"onsetMilliseconds": 1250,
"subdivision": 2
},
{
"accent": 0.375,
"beat": 4,
"onsetMilliseconds": 1500,
"subdivision": 1
},
{
"accent": 0.375,
"beat": 4,
"onsetMilliseconds": 1750,
"subdivision": 2
}
]
}
}
}Subdivisions one produces beat ticks only. The final onset precedes the measure duration by one subdivision step; no extra event is added at the next measure’s onset. An invalid first draw still fails despite its fixed accent.
Limitations and assumptions
The default source is Math.random; no seed input or cryptographic entropy guarantee is provided. Repeated runs may select the same result, and the distribution depends on the random source.
There is no swing, irregular subdivision, rests, tempo ramp, sound selection, audio scheduling, or MIDI velocity conversion. Accent values are not decibels or a specified loudness scale.
Only one measure is generated. A caller must decide whether to repeat it unchanged or request a new random pattern for later measures.
Alternative or Complementary methods
Use a deterministic beat-duration conversion for one timing calculation. A tempo-synced delay generator offers note-division durations rather than onset events.
References
Similar or alternative tools
- BPM to Milliseconds
Calculate one beat duration from a supplied tempo.
- Random Tempo-Synced Delay Preset Generator
Choose rhythmic delay durations under its quarter-note convention.