Pre-Delay Calculator

Place reverb pre-delay on rhythmic subdivisions. It is designed for vocal mixers and sound designers separating a dry transient from its reverb.

By the PulseKit editorial team · Formula and interface reviewed July 14, 2026

The calculation in one line

Start with a short subdivision. Increase it only while the dry source remains connected to the ambience.

Worked example

At 100 BPM a sixteenth note is 150 ms and a thirty-second note is 75 ms.

How does pre-delay change perceived depth?

A short gap keeps the reverb attached to the source. More separation can preserve consonants and transients while making the ambience feel farther behind. Excessive pre-delay becomes a distinct echo and can disconnect the room from the performance.

Three checks before using the answer

• Begin with a sixteenth or thirty-second value.
• Audition in the full mix, not only in solo.
• Compare the dry transient with the first early reflections.

A detail that changes the interpretation

Some reverbs include inherent algorithmic onset time, so the audible gap can exceed the number entered in the pre-delay field.

Most common mistake

Using a long rhythmic value by default. Large pre-delay can sound like a separate echo rather than room onset.

Where the calculation stops

Many natural spaces do not produce a single discrete pre-delay, so the musical value is an artistic approximation.

Research note

The calculated subdivision is a musical starting point; room geometry is not inferred. Read MDN’s Web Audio API overview. External documentation supports the technical context; its publishers do not endorse PulseKit.

Questions musicians ask

Inputs stay on this device. Display rounding never changes the underlying formula.