Reverb Pre-Delay Guide
Reverb pre-delay is one of the most important and underused mixing tools. A small time gap between your dry signal and the reverb tail keeps transients clear, lets instruments sit forward in the mix, and makes reverb sound natural rather than washy.
This guide explains how pre-delay works, when to use it, and gives you a complete BPM-synced pre-delay chart for every tempo.
What Is Reverb Pre-Delay?
Without Pre-Delay
Reverb starts the instant the note plays. The dry signal and reverb tail blur together, burying the attack and making the instrument sound distant or washy.
With Pre-Delay
A small gap (10-60ms) delays the reverb start. The dry transient rings out first, clear and audible, then the reverb blooms behind it. The instrument sits forward in the mix.
The Goal
Maximum reverb presence without losing clarity. Pre-delay lets you use wetter, bigger reverb settings while keeping the source instrument clean and forward.
BPM-Synced Pre-Delay Formula
8th note at 120 BPM:
60,000 / 120 / 2 = 250ms
(usually too long for pre-delay)
16th note at 120 BPM:
60,000 / 120 / 4 = 125ms
(can work for hall reverb on slower songs)
32nd note at 120 BPM:
60,000 / 120 / 8 = 63ms
(common starting point for vocals)
BPM Pre-Delay Reference Chart
Pre-delay times in milliseconds for each tempo. Start with the 32nd note value for vocals and most instruments. Use 16th note for longer, more spacious reverbs on slower songs.
| BPM | 8th Note | 16th Note | 32nd Note |
|---|---|---|---|
| 70 | 429ms | 214ms | 107ms |
| 80 | 375ms | 188ms | 94ms |
| 85 | 353ms | 176ms | 88ms |
| 90 | 333ms | 167ms | 83ms |
| 95 | 316ms | 158ms | 79ms |
| 100 | 300ms | 150ms | 75ms |
| 105 | 286ms | 143ms | 71ms |
| 110 | 273ms | 136ms | 68ms |
| 115 | 261ms | 130ms | 65ms |
| 120 | 250ms | 125ms | 63ms |
| 125 | 240ms | 120ms | 60ms |
| 128 | 234ms | 117ms | 59ms |
| 130 | 231ms | 115ms | 58ms |
| 135 | 222ms | 111ms | 56ms |
| 140 | 214ms | 107ms | 54ms |
| 150 | 200ms | 100ms | 50ms |
| 160 | 188ms | 94ms | 47ms |
| 170 | 176ms | 88ms | 44ms |
| 175 | 171ms | 86ms | 43ms |
| 180 | 167ms | 83ms | 42ms |
32nd note values are typically the most useful starting point for reverb pre-delay. Go lower (non-BPM values of 10-25ms) for tight room/snare reverb.
Pre-Delay by Instrument
Lead Vocals
20-60msSeparates the dry voice from the reverb tail so both are audible. Without pre-delay, reverb muddles the vocal transient and makes it sit behind the mix.
Start at one 16th note at your session BPM. A/B with and without pre-delay on solo vocals.
Snare Drum
10-30msPreserves the snare crack. Without pre-delay, room reverb smears the attack and the snare loses punch and presence in the mix.
Keep it tight: 10-20ms for punchy pop/rock snare. Up to 30ms for more ambient feels.
Electric Guitar
15-40msMaintains the pick attack. Especially critical for single-note leads and clean chords in dense arrangements where guitar needs to cut through.
Less pre-delay for rhythm guitar (rhythmic tightness). More for lead guitar (space to breathe).
Piano / Rhodes
20-50msRetains the key attack transient. Rhodes especially benefits since the hammer mechanism creates a distinctive percussive attack that reverb can bury.
Longer pre-delay (40-60ms) for solo piano. Shorter (15-25ms) for piano in busy arrangements.
Synth Leads
10-35msStops the synth from sounding blurry. Especially important for fast runs and arpeggios where note separation matters.
For pad-like leads, skip pre-delay entirely and let reverb blend. For melodic leads, use 20-30ms.
Acoustic Guitar / Strings
25-60msAcoustic instruments with natural sustain need pre-delay to sit in a realistic sonic space without sounding like they were recorded inside the reverb unit.
Match pre-delay to the room size: short for small room reverb, longer for hall reverb.
Pre-Delay by Reverb Type
| Reverb Type | Typical Pre-Delay |
|---|---|
| Room | 5-20ms |
| Hall | 20-60ms |
| Plate | 15-35ms |
| Spring | 0-15ms |
| Chamber | 10-30ms |
| Ambience / Space | 5-25ms |
Famous Examples of Reverb Pre-Delay
Total Eclipse of the Heart (1983)
by Bonnie Tyler / Jim Steinman ~30-40msEpic 80s reverb with noticeable pre-delay on the vocal. The space between the dry vocal and the cavernous reverb tail is what made this sound so massive and cinematic.
In The Air Tonight (1981)
by Phil Collins ~20-35msThe gated reverb on the snare (not true reverb pre-delay, but same principle) uses timing to separate the attack from the release. The pre-delay equivalent makes each snare hit punch through.
When Doves Cry (1984)
by Prince ~15-25msPrince famously removed the bass guitar, so reverb pre-delay on drums and synths was essential to maintain clarity. The dry attack of every element cuts through despite the lush verb.
I Will Always Love You (1992)
by Whitney Houston / David Foster ~25-40msMasterclass in vocal reverb with pre-delay. The dry Whitney voice is completely clear for the first 30-35ms before the plate reverb bloom. This is why the vocal sounds both intimate and enormous.
Midnight City (2011)
by M83 ~20-40msModern example of textbook reverb pre-delay on synth leads and vocals. The massive hall reverbs never cloud the forward-sitting dry signals because of careful pre-delay across the entire mix.
Pro Tips for Reverb Pre-Delay
1. High-Pass the Reverb Return
Always high-pass filter your reverb return (typically 200-400Hz for vocals, 100-200Hz for instruments). This stops reverb from muddying the low end and makes pre-delay placement more audible.
2. Automate Pre-Delay
Use longer pre-delay during verses (more intimate, close feel) and shorter or no pre-delay during choruses (reverb blooms immediately for a wall-of-sound effect). Automation can make this transition dynamically.
3. A/B With and Without
Bypass the pre-delay (set to 0ms) and listen. If your reverb sounds muddy or the instrument loses presence, add pre-delay in 5ms increments until clarity returns. Your ears will tell you the right amount.
4. Use a Send/Return Setup
Always put reverb on a send track, not directly on the channel. This lets you set the pre-delay once and route multiple instruments to the same reverb, creating a cohesive sense of space in your mix.
5. Pre-Delay on Bus Compressors
Some mixing engineers add a short delay (5-15ms) before a bus reverb, separate from the reverb's built-in pre-delay parameter. This creates a more realistic first reflection that mimics real room acoustics.
6. Check in Mono
Pre-delay can create phase issues when stereo reverb is summed to mono. Always check your reverb settings in mono to ensure the pre-delay gap doesn't cause comb filtering or the reverb to disappear.
Frequently Asked Questions
What is reverb pre-delay?
Reverb pre-delay is a small time gap (usually 5-60ms) between the dry signal and the start of the reverb tail. It prevents reverb from burying the attack of an instrument or vocal. Most reverb plugins have a dedicated pre-delay knob measured in milliseconds.
How do I calculate BPM-synced reverb pre-delay?
Divide 60,000 by your BPM to get one beat in milliseconds, then divide by the note subdivision. For a 32nd note at 120 BPM: 60,000 / 120 / 8 = 62.5ms. Use the chart above for quick lookup at any BPM. The BeatKey Delay Calculator gives you all note values for any BPM instantly.
Should reverb pre-delay always be synced to BPM?
Not necessarily. BPM-synced pre-delay creates a rhythmic relationship between the reverb and the groove, which works well in electronic and pop production. For natural acoustic reverb (orchestral, jazz, ambient), use pre-delay based on the reverb type and source material rather than strict BPM sync. Use your ears as the guide.
What pre-delay should I use for vocals?
Start with one 32nd note at your session BPM. At 120 BPM that is 62.5ms. A practical range for most vocal reverb is 20-50ms. Short pre-delay (10-20ms) keeps the vocal tight. Long pre-delay (40-60ms) creates space and grandeur. The drier and more upfront the vocal needs to sound, the longer the pre-delay.
Calculate Pre-Delay for Your BPM
Use the full BeatKey Delay Calculator to get every note value for any BPM. Covers whole, half, quarter, 8th, 16th, 32nd notes plus dotted and triplet variants.
Open Delay Calculator