BEATTIMINGTOOLS FOR MAKING MUSIC
Tempo-aware space

Reverb timing calculator

Calculate reverb pre-delay and decay times from BPM. Get tempo-synced millisecond starting points for vocals, drums and instruments, then adjust by ear.

Reverb timing: settings and guide

Pre-delay starting points
1/64 note31.25 ms
1/32 note62.5 ms
1/16 note125 ms
1/8 note250 ms
Decay starting points
Half beat250 ms
One beat500 ms
Two beats1,000 ms
One 4/4 bar2,000 ms

These are tempo-related starting points, not mix rules. Adjust by ear for the source, arrangement and reverb algorithm.

Hear delay timing at 120 BPM ↗
Formula

How to calculate tempo-based reverb timing

Tempo divisions give repeatable starting points for reverb pre-delay and decay. Short subdivisions can separate the dry transient from the reverb onset, while longer beat or bar values can help a tail end near a musical boundary.

timing value (ms) = 60,000 ÷ BPM × rhythmic multiplier

  1. 01

    Pre-delay separates the dry transient from the reverb and can improve clarity.

  2. 02

    Use the short values as starting points, then adjust by ear for the source and room character.

  3. 03

    Tempo-related decay values can help a reverb tail clear before the next important phrase.

Worked example

Example: reverb timing at 120 BPM

At 120 BPM, a 1/64-note starting point is 31.25 ms, a 1/32 note is 62.5 ms, and one 4/4 bar is 2,000 ms. A short value can guide pre-delay; a longer value can guide a decay time.

Good to know

Assumptions and limits

  • These are musical starting points, not rules for a specific room or source.
  • A reverb plugin's decay control may describe RT60 rather than the exact moment its tail becomes silent.
  • Final pre-delay and decay settings should be checked in the full mix.
  • Displayed values use up to nine significant digits; calculations retain the unrounded value.

Review BeatTiming's calculation accuracy, precision and release-testing methodology.

A listening exercise

Keep a vocal clear at 96 BPM

Loop a short vocal phrase that ends before the next line. Try a 1/64-note pre-delay of 39.0625 ms and a two-beat decay reference of 1.25 seconds. These are starting points for this exercise, not a preset that suits every singer or reverb.

  1. Read two separate controls. Enter 96 above. Pre-delay determines when the reverb begins; decay describes how its level falls afterward. Convert the 1,250 ms decay result to 1.25 seconds if your plugin uses seconds.
  2. Compare the onset. In Ableton Live 12's Reverb, keep Decay at 1.25 s and compare Predelay at 0 ms and about 39 ms. Keep the wet/dry balance fixed. Listen for how clearly the first consonant or attack separates from the reverb.
  3. Compare the tail. Hold Predelay near 39 ms, then compare Decay at 1.25 s and 0.625 s. Listen during the gap before the next line. Shorten the decay if that gap becomes crowded; adjust the wet level separately.
  4. Check in the song. Compare with the drums and accompaniment playing. A longer pre-delay can become a noticeable echo. Recalculate tempo-based millisecond values if the project BPM changes.
Two independent reverb settings at 96 BPM
ControlReferenceMeaning
Pre-delay39.0625 ms1/64 note before reverb onset
Decay1.25 sTwo-beat duration as a decay setting

Ableton Reverb's Decay describes a drop to −60 dB. It does not mark an exact moment of silence. Adding pre-delay shifts the onset; it does not subtract time from the decay setting.

Control definitions: Ableton Live 12 Reverb reference. Use the nearest value your plugin accepts; 39 ms is close to the calculated 39.0625 ms.

120 BPM reference

Reverb pre-delay and decay times by BPM

At 120 BPM, 31.25 ms is a 1/64-note starting point, 62.5 ms is a 1/32 note and 125 ms is a 1/16 note. One 4/4 bar is 2,000 ms. Treat these as musical starting points: a reverb's RT60 decay is not the exact moment its tail becomes silent.

A delay time sets the interval between distinct repeats. A reverb decay control often describes RT60—the time for the reverberant level to fall by 60 dB—so it is not a promise that the tail becomes silent at that exact value.

Tempo-related starting points

Reverb timing starting points at 120 BPM
Note valueTime at 120 BPMPossible use
1/64 note31.25 msShort pre-delay
1/32 note62.5 msPre-delay
1/16 note125 msLong pre-delay / short space
One 4/4 bar2,000 msDecay reference
Quick answers

Frequently asked questions

Is there one correct pre-delay setting?

No. Tempo gives useful starting points, while the source, arrangement and desired depth determine the final setting.

What does a longer pre-delay do?

It creates more separation between the dry sound and the reverb onset, often making the source feel closer and clearer.

Should every reverb use the same timing?

Not necessarily. Related rhythmic values can unify a mix while different spaces may need different decay lengths.