Reverb and Delay Calculator

Calculator Inputs

Project name

Tempo BPM

Beats per bar

Delay note value

Delay feel

Pre-delay mode

Manual pre-delay ms

Delay feedback %

Wet level %

Dry level %

Reflection distance meters

Air temperature °C

Target RT60 seconds

Room length meters

Room width meters

Room height meters

Diffusion target %

Reverb density %

Sample rate

Mix notes

Example Data Table

BPM	Quarter delay	Dotted eighth	Eighth triplet	Suggested use
90	666.67 ms	500.00 ms	222.22 ms	Ballad vocal space
120	500.00 ms	375.00 ms	166.67 ms	Pop lead echo
140	428.57 ms	321.43 ms	142.86 ms	Fast rhythmic repeat
160	375.00 ms	281.25 ms	125.00 ms	Tight dance mix

Formula Used

Quarter note milliseconds: 60000 ÷ BPM.

Delay time: quarter note milliseconds × note factor × feel factor.

Dotted feel: selected delay × 1.5.

Triplet feel: selected delay × 2 ÷ 3.

Delay frequency: 1000 ÷ delay milliseconds.

Samples: milliseconds ÷ 1000 × sample rate.

Speed of sound: 331.3 + 0.606 × temperature in Celsius.

Distance pre-delay: distance ÷ speed of sound × 1000.

Early reflection: two-way distance ÷ speed of sound × 1000.

Sabine absorption estimate: 0.161 × room volume ÷ target RT60.

Repeats to -60 dB: log(0.001) ÷ log(feedback ratio).

How to Use This Calculator

Enter the song tempo in BPM.
Select the main note value for the delay.
Choose straight, dotted, or triplet timing.
Set feedback, wet level, dry level, and density.
Add room size, reflection distance, and RT60 target.
Choose a musical or manual pre-delay setting.
Press the calculate button.
Review the result above the form.
Use CSV or PDF export for session notes.

Reverb And Delay Planning Guide

Why Timing Matters

Good ambience starts with timing. A delay that follows the song tempo feels connected. A delay that misses the groove feels random. This calculator helps turn musical choices into exact values. It gives milliseconds, hertz, samples, and tail estimates. These numbers help during tracking, editing, mixing, and live setup.

Tempo Based Delay

Tempo based delay is usually built from quarter notes. One beat equals sixty thousand divided by BPM. Longer notes multiply that value. Shorter notes divide it. Dotted notes add half the chosen value. Triplets use two thirds of the chosen value. These simple changes create very different rhythms.

Pre-delay And Space

Pre-delay controls the gap before reverb becomes obvious. A short setting can glue a vocal to the room. A longer setting can keep words clear. Many engineers set pre-delay from tempo. Others base it on distance. Both methods are useful. This tool shows each approach together.

Decay Decisions

Reverb decay describes how long reflections stay audible. A small room may need a short tail. A ballad may support a longer tail. Fast music often needs less decay, because notes arrive quickly. Dense mixes also need careful timing. Long tails can blur drums, bass, and consonants.

Room Planning

Room size also matters. Volume, surface area, and target decay create a practical absorption estimate. The value is not a full acoustic design. It is a planning guide. It shows whether the chosen decay feels realistic. It also helps compare rooms and virtual spaces.

Feedback And Balance

Feedback changes delay length beyond the first echo. More feedback means more repeats. Less feedback makes a tighter effect. Wet and dry balance decides how forward the effect sounds. A high wet level can feel dreamy. A low wet level can add depth without distraction.

Practical Workflow

Use the result as a starting point. Then adjust by ear. Solo listening can be helpful. Full mix listening is more important. The best value supports the song, the arrangement, and the emotion. For best results, save common settings for each genre. Compare vocals, guitars, drums, and pads separately. Each source needs a different space. Small changes can solve masking. Export the table after testing. Keep notes about the preset, tempo, and arrangement. These records make future sessions faster and more consistent over time with confidence.

FAQs

What does this calculator find?

It finds tempo synced delay times, pre-delay values, sample counts, repeat estimates, and room decay guidance for music mixing and sound design.

What is BPM in delay timing?

BPM means beats per minute. The calculator uses it to convert musical note values into exact milliseconds for delay and pre-delay settings.

Should I use dotted delay?

Dotted delay is useful when you want movement between beats. It often works well on vocals, guitars, synths, and lead melodies.

What does triplet delay mean?

Triplet delay divides timing into three equal parts. It creates a rolling feel and can add swing, bounce, or rhythmic tension.

What is pre-delay?

Pre-delay is the gap before the reverb begins. It can keep a vocal clear while still adding space and depth.

What is RT60?

RT60 is the time needed for reverb to decay by 60 dB. It describes how long a space remains audible.

Why are samples shown?

Samples help with precise editing and plugin settings. They are useful when working inside digital audio software or hardware samplers.

Can I export the result?

Yes. After calculation, use the CSV or PDF button to save the result table for session recall and documentation.