Reverb Pre-Delay: What It Is and How to Set It to Tempo

The short answer: pre-delay is the short gap between the dry sound and the moment its reverb starts. A little gap (roughly 10 to 120 ms) lets the attack of a vocal or drum land clean and in front, then the reverb blooms behind it, so you get space without losing clarity. The musical way to set it is to tempo: use a small note value (often a 1/64 or 1/128 note) for pre-delay, and set the decay so pre-delay plus decay equals a beat, a half note, or a bar. The delay and reverb time calculator does the math for any tempo.

Tempo-synced pre-delay is on every vocal reverb in my own mixes (Sony, Universal, Ultra, Dim Mak releases). It's the cheapest way to make reverb sound expensive.

Why pre-delay matters

In a real room, you hear the direct sound first and the reflections a moment later. That gap tells your brain the sound is close and the space is around it. With zero pre-delay, the reverb starts at the same instant as the sound, smearing consonants and transients, and the source seems to sink back into the wash. Add a short gap and the source jumps forward again while keeping the space.

Typical settings

How to set it to the tempo

1. Pick the space. Decide how long the whole reverb should last: a bar for a big hall, a half note for a large room, a beat for a small room.
2. Set pre-delay to a small note value. A 1/64 note works for halls, a 1/128 note for tighter rooms. At 120 BPM, a 1/64 note is 31.25 ms.
3. Set decay so the total fits. Decay = total length minus pre-delay. At 120 BPM, a hall lasting one bar (2,000 ms) with 31.25 ms of pre-delay needs about 1,969 ms of decay.
4. Adjust by ear. These are starting points. If the tail still masks the next phrase, shorten the decay; if the vocal feels detached, shorten the pre-delay.

Doing that division mid-session is a mood killer, which is exactly why the calculator shows pre-delay, decay, and total for four room sizes at any BPM. Tap a value and it's copied.

Mistakes that make reverb washy

• Reverb on the insert instead of a send. Use a send so the dry sound stays intact and you can process the return.
• No EQ on the return. High-pass around 200 to 400 Hz and tame the highs. Low-end reverb is mud; bright reverb exaggerates sibilance, so de-ess before the send.
• Decay longer than the gaps. If the tail is still ringing when the next line starts, it blurs everything. Tempo-synced decay prevents it.
• Reverb where delay would work better. On vocals, delay often gives space with more clarity; the vocal delay guide covers when to choose which.

Reverb is the final space stage of a vocal chain, and like all width, it should survive a mono check.

Quick answers

What is pre-delay on a reverb? The time between the dry sound and the start of the reverb. It keeps the source clear and in front while the space builds behind it.

What is a good pre-delay for vocals? Around 30 to 80 ms for a lead vocal, or a 1/64 note at the song's tempo. Go shorter for background vocals you want blended into the space.

Should pre-delay be synced to the tempo? It doesn't have to be, but tempo-synced pre-delay and decay make the reverb move with the groove and clear before the next phrase.

How do I calculate reverb decay from BPM? Choose a total length (one beat = 60,000 ÷ BPM ms), subtract the pre-delay, and the rest is your decay. The calculator does it for any tempo.