Delay Reverb Times
Calculate note durations in milliseconds from BPM and time signature. Free pre-delay and decay time calculator for music producers, audio engineers, and live sound mixing.
About This Calculator
The Delay Reverb Times Calculator helps music producers, audio engineers, and sound designers calculate precise note durations in milliseconds from a song's BPM and time signature. Getting delay and reverb effect times synced to your track's tempo is essential for clean, professional mixes where the effects don't clash with the rhythm.
The calculator uses the standard formula: quarter note (ms) = 60,000 ÷ BPM. From this base value, it derives all standard note divisions — whole notes (×4), half notes (×2), quarter notes (×1), eighth notes (÷2), sixteenth notes (÷4), and thirty-second notes (÷8). The pre-delay feature lets you choose a shorter note value during which the reverb or delay effect is delayed, helping maintain clarity while keeping the effect in sync. Decay time is then calculated as the total note duration minus the pre-delay duration.
In music production, properly timed reverb and delay can make the difference between a muddy mix and a polished track. A delay that's too short will overlap with the next note, while one that's too long will sound disconnected from the rhythm. This tool works for any genre and any tempo, from slow ballads at 60 BPM to fast electronic music at 180 BPM.
The pre-delay control is particularly important for reverb. A longer pre-delay (like 1/8th note) pushes the reverb further back in time, preserving the attack of the instrument. A shorter pre-delay or no pre-delay creates a more ambient, washed-out effect. These principles apply universally across all music production environments — whether you're using a DAW plugin, a hardware effects unit, or a live mixing console.
Frequently Asked Questions
How do I calculate delay time from BPM?
To calculate delay time from BPM, divide 60,000 by the BPM value. For example, at 120 BPM the quarter note duration is 60,000 ÷ 120 = 500 ms. Half notes are double (1,000 ms), eighth notes are half (250 ms), and sixteenth notes are a quarter (125 ms) of the quarter note duration.
What is pre-delay in reverb?
Pre-delay is the amount of time in milliseconds before the reverb or delay effect becomes audible after a note is played. It creates space between the dry signal and the wet effect, helping maintain clarity in mixes. Common pre-delay values range from 1/64th note to 1/8th note durations depending on the tempo.
How do I calculate decay time for reverb?
Decay time is calculated by subtracting the pre-delay time from the total note duration. For example, if the quarter note is 500 ms and the pre-delay is set to 1/16th note (125 ms), the decay time would be 500 - 125 = 375 ms. This ensures the reverb effect fully decays before the next note.
What is the difference between delay and reverb?
Delay replicates the original sound multiple times at decreasing volume levels (echo effect), while reverb simulates the sound reflecting off surfaces in a physical space like a room or hall. Both effects are measured in milliseconds and should be synced to the song's tempo for best results.
What time signature should I use for delay calculations?
The time signature determines which note value gets the beat. In 4/4 and 3/4 time, the quarter note gets the beat. In 2/2 (cut time), the half note gets the beat. In 6/8 time, the eighth note typically gets the beat. The calculator uses the quarter note as the reference for all note division calculations.
How long is a quarter note in milliseconds at 120 BPM?
A quarter note at 120 BPM is 500 milliseconds. This is calculated by dividing 60,000 (milliseconds in a minute) by the BPM: 60,000 ÷ 120 = 500 ms. This is a standard reference point used by audio engineers to set delay and reverb times that stay in sync with the music.
Can I use this calculator for live sound mixing?
Yes, this delay and reverb time calculator is ideal for live sound engineers who need to quickly set delay and reverb effects in sync with the band's tempo. Simply enter the BPM of the current song and choose your pre-delay division to get accurate millisecond values for your effects processors.