90 BPM

Beat, bar and phrase lengths at 90 BPM

At 90 BPM one beat lasts 666.67 ms and a 4/4 bar lasts 2.667 s. The beat is not a whole number of milliseconds, so round to the nearest 0.1 ms when you type times in by hand, or use your plugin's tempo sync. That is 1.5 beats per second, or 22.5 bars of 4/4 per minute.

Dance tracks are usually arranged in 8-, 16- and 32-bar phrases. At 90 BPM a 16-bar phrase takes 42.67 s and a 32-bar intro or outro takes 1:25.3 min. That is 10.67 s longer than the same 16 bars at 120 BPM. A six-minute track at this tempo contains about 135 bars.

Delay times at 90 BPM

Straight values follow the beat; dotted values are 1.5 times as long and triplets are two-thirds as long. At 90 BPM the popular dotted-eighth delay is 500 ms and a quarter-note slapback is 666.67 ms. The Hz column is the matching rate for an LFO, tremolo or auto-pan synced to the straight note.

Reverb times at 90 BPM

A common way to keep a reverb in time is to tie its pre-delay to a short note value and let the tail fade within a longer one. At 90 BPM a 1/64-note pre-delay is 41.67 ms and a 1/32-note pre-delay is 83.33 ms.

The decay control on most reverbs is RT60, the time it takes the tail to fall by 60 dB, so the audible tail ends earlier than the number shown. Treat these values as starting points and adjust by ear.

Genres at 90 BPM

90 BPM is a relaxed, mid-slow tempo. It sits near the upper end of the ambient/downtempo range (60–100), in the middle of the hip-hop range (70–100), in the middle of the reggae/dub range (70–100), near the low end of the reggaeton/dembow range (88–100) and at the bottom of the pop range (90–130).

Counted at double-time (180 BPM) it matches drum and bass and hardcore/gabber. A detector or a tag in your library may report either reading, so check by ear which one the drums suggest.

These ranges are common practice rather than rules: genre is decided by rhythm, sound and scene as much as by tempo, and plenty of tracks sit outside the usual numbers.

• Ambient/downtempo: typically 60–100 BPM — beatless ambient may not have a useful BPM at all.
• Hip-hop: typically 70–100 BPM — boom-bap often sits around 85–95.
• Reggae/dub: typically 70–100 BPM — the off-beat skank can make the pulse feel faster than it is.
• Reggaeton/dembow: typically 88–100 BPM — the dembow rhythm repeats every beat, so the tempo is easy to hear.
• Pop: typically 90–130 BPM — a wide band; the genre is defined by songwriting, not tempo.

Mixing into 90 BPM

To bring a track at another tempo up or down to 90 BPM, move its pitch fader by the percentage below. Without key lock the key moves too, by the number of semitones shown; about 6 % is one semitone, so changes beyond that are where key lock (master tempo) starts to matter.

A ±8 % pitch fader on a track at 90 BPM reaches 82.8–97.2 BPM; a ±16 % range reaches 75.6–104.4 BPM.

Half-time, double-time and nearby tempos

Half-time of 90 BPM is 45 BPM and double-time is 180 BPM.

45 BPM is outside the 60–200 range of these pages; the half/double-time converter works with any value.

Each 1 BPM step at this tempo changes the beat by about 7.33 ms, so neighbouring tempos are close enough to beatmatch with a small pitch move.

• Double-time: 180 BPM
• 85 BPM
• 88 BPM
• 89 BPM
• 91 BPM
• 92 BPM
• 95 BPM
• Half/double-time converter
• All tempos from 60 to 200 BPM