Enter the tempo
Use the BPM from your project or select one of the quick preset buttons.
This reverb pre-delay calculator converts BPM into precise millisecond values for straight, dotted and triplet note divisions. Use it to find tempo-related starting points for the pre-delay control in your reverb, then fine-tune the result by ear.
Enter your project tempo and compare musical timing divisions from whole notes down to 1/64 notes. Straight, dotted and triplet values update instantly in milliseconds.
Enter the BPM from your session or choose a quick preset.
Calculated for 120 BPM
Milliseconds
| Note | Straight | Dotted | Triplet | Copy |
|---|
Pre-delay is the time between the dry sound and the beginning of the audible reverb response. Instead of choosing that time only as an arbitrary number of milliseconds, you can derive timing values from the tempo of the music.
Enter the BPM and the calculator first determines the duration of one quarter-note beat. It then derives whole, half, quarter, eighth, sixteenth, thirty-second and sixty-fourth-note timings, along with dotted and triplet variations.
The result is a set of precise millisecond references you can try in a reverb plug-in. If you also want to experiment with overall balance and signal relationships, open the Interactive Online Audio Mixer or explore the Mixer Console Simulator.
The calculator gives you tempo-related timing points, but it does not prescribe a single correct setting. Use the calculated value as a reference, then listen to how the dry sound and reverb interact in the actual arrangement.
When pre-delay is very short, the reverb begins close to the dry sound. As the value increases, a clearer time gap develops before the reverberant response arrives. That separation can change how the source, its transients and the surrounding ambience are perceived.
The effect is easy to understand with vocals. A vocal can begin clearly, while the reverberant field follows slightly later. The same principle can be explored on drums, guitars, keyboards, orchestral parts, sound design and many other sources.
For more context around capturing different sources before effects are applied, see our audio content recording overview and the guide to recording musical instruments.
A millisecond value can be chosen freely, but deriving it from BPM creates a known relationship with the musical pulse. At a different song tempo, the same note division produces a different number of milliseconds, so the timing follows the speed of the music.
This can be particularly useful when comparing several reverb settings. Instead of trying unrelated numbers, you can move between 1/64, 1/32, 1/16 and other musical divisions and hear how each relationship changes the sense of space.
If you are still building familiarity with studio workflows, the First Time Recording Studio Guide covers the broader recording process, while the audio tools collection provides more browser-based resources for recording and listening.
Use the BPM from your project or select one of the quick preset buttons.
Check straight, dotted and triplet values from long note divisions down to short pre-delay references.
Copy a millisecond value into your reverb and adjust it while listening to the full arrangement.
A reverb pre-delay tool makes it easy to move between musical subdivisions and the millisecond values used by many reverb processors. The table keeps multiple options visible at once, making comparison faster when you are shaping space around a source.
One minute contains 60,000 milliseconds. Dividing that number by the project BPM gives the duration of a quarter note. The remaining values are calculated from that beat duration.
Quarter note = 60,000 ÷ BPM 1/8 = quarter ÷ 2 1/16 = quarter ÷ 4 1/32 = quarter ÷ 8 1/64 = quarter ÷ 16Straight subdivisions follow the normal binary division of the beat. Each step halves or doubles the duration of the neighboring value. This makes it simple to move between longer and shorter timing relationships while keeping them connected to the tempo.
A dotted value is one and a half times its straight equivalent. Because it sits at a different rhythmic position than the straight division, it provides another family of timing options without abandoning the BPM relationship.
Dotted = straight × 1.5Triplet values are two-thirds of the corresponding straight duration in this table. They provide shorter intermediate timings that can be useful when the straight value feels too long for the source or arrangement.
Triplet = straight × 2 ÷ 3Pre-delay is only one parameter inside a reverb. Decay time, early reflections, diffusion, filtering, room character and wet level also shape the result. Judge the calculated timing together with the complete effect.
A reverb pre-delay calculator online is useful when your project already has a defined BPM and you want immediate timing references without calculating each subdivision manually. Enter the tempo once and compare the entire table.
For example, you can start with a short 1/64 or 1/32 value, compare it with the corresponding triplet timing, and then move toward a longer 1/16 value. The purpose is not to find a universally correct number but to make controlled comparisons that remain connected to the musical tempo.
On vocals, the relationship between the dry performance and the reverb onset can be especially noticeable. A short setting can make the ambience begin close to the voice, while increasing the gap can create more temporal separation before the reverberant sound develops.
Phrase length and arrangement density also matter. A timing that sounds spacious in one section may interact differently with a faster or denser passage. Our article on vocal recording session timing looks at the broader vocal workflow, while the Music as the Language of the Soul page explores the creative side of musical expression.
BPM and milliseconds move in opposite directions. As BPM increases, each beat becomes shorter, so every note-derived pre-delay value decreases. At a slower tempo, the same musical subdivision occupies more time and produces a larger millisecond value.
That means a pre-delay value copied from one song does not preserve the same rhythmic relationship when the tempo changes. Recalculate the timing for the new BPM if you want to maintain the same musical subdivision.
Whole, half and quarter notes are included so the complete timing relationship remains visible, but reverb pre-delay often invites comparison of much shorter divisions. For that reason, the table continues through 1/32 and 1/64 notes and highlights several short values directly beside the BPM controls.
You can still experiment with any of the longer values when the creative effect calls for it. The calculator simply gives you the timing map; the reverb and arrangement determine what is musically useful.
Pre-delay controls when the reverberant response begins, while decay describes how the reverb develops and fades afterward. They should not be treated as interchangeable settings. A short pre-delay can be paired with a long decay, and a longer pre-delay can be used with a much shorter reverb.
When learning how effects sit inside a complete signal path, the mixer console simulator offers another interactive way to explore mixing concepts. You can also browse blues and country recording for an example of how production choices relate to different musical material.
The main advantage of calculated timing is repeatability. You know exactly how the chosen millisecond value relates to the project BPM, and you can move deliberately between straight, dotted and triplet alternatives instead of selecting unrelated numbers.
Once you have a starting value, listen to the reverb against the complete mix. The most useful setting is the one that supports the source and arrangement, whether it lands exactly on a calculated subdivision or is adjusted away from it.
Reverb timing is one part of creating depth and perspective. Continue with related tools and articles covering recording, performance and production.
Continue with browser-based tools for musicians, recording, mixing, timing and critical listening in the Ronter Audio Lab.
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