Delay Time Calculator
Calculate delay and reverb times in milliseconds from BPM for music production. Enter values for instant results with step-by-step formulas.
Formula
Delay (ms) = (60,000 / BPM) x Note Multiplier
The base quarter note duration in milliseconds equals 60,000 divided by the BPM. Multiply this by the note value factor: 4 for whole, 2 for half, 1 for quarter, 0.5 for eighth, 0.25 for sixteenth. Dotted notes multiply by 1.5, and triplets multiply by 2/3 of the next larger note value.
Worked Examples
Example 1: Synced Delay for Pop Production at 128 BPM
Problem: Set up a tempo-synced stereo delay for a vocal track at 128 BPM using dotted eighth note on the left and quarter note on the right.
Solution: Quarter note = 60000 / 128 = 468.75 ms\nDotted eighth = 468.75 x 0.75 = 351.56 ms (left channel)\nQuarter note = 468.75 ms (right channel)\nSamples at 44.1kHz: Left = 15504, Right = 20672\nSamples at 48kHz: Left = 16875, Right = 22500
Result: Left: 351.56 ms (dotted 8th) | Right: 468.75 ms (quarter) | Creates a ping-pong rhythm effect
Example 2: Reverb Pre-Delay for Orchestral Mix at 72 BPM
Problem: Calculate appropriate reverb pre-delay values for a slow orchestral piece at 72 BPM to maintain clarity on lead instruments.
Solution: Quarter note = 60000 / 72 = 833.33 ms\nShort pre-delay (1/64 note) = 833.33 x 0.0625 = 52.08 ms\nMedium pre-delay (1/32 note) = 833.33 x 0.125 = 104.17 ms\nLong pre-delay (1/16 note) = 833.33 x 0.25 = 208.33 ms\nRecommended: 52-104 ms for strings, 104 ms for brass
Result: Short: 52ms | Medium: 104ms | Long: 208ms | Use medium for balanced spaciousness
Frequently Asked Questions
What is a delay time calculator and why do music producers use it?
A delay time calculator converts BPM (beats per minute) to milliseconds for various note subdivisions, allowing music producers to synchronize delay and echo effects with the tempo of their song. When delay times are mathematically locked to the tempo, the echoes fall on rhythmically meaningful positions, creating a cohesive and musical effect rather than a chaotic or dissonant one. Without proper synchronization, delay repeats can clash with the beat, muddying the mix and creating unwanted rhythmic conflicts. Modern DAWs often have tempo-synced delay plugins, but many hardware units, analog delays, and certain creative workflows require manual millisecond entry, making this calculation essential for professional production.
How do you calculate delay time from BPM?
The fundamental formula is: Delay Time (ms) = 60,000 / BPM for a quarter note. This works because there are 60,000 milliseconds in one minute, so dividing by the number of beats per minute gives the duration of one beat in milliseconds. For other note values, you multiply this base value by the appropriate factor. A half note is 2 times the quarter note value, a whole note is 4 times, an eighth note is half, and a sixteenth note is a quarter of the base value. Dotted notes multiply by 1.5 (adding half the note value), while triplet notes multiply by two-thirds. For example, at 120 BPM: quarter note = 500ms, dotted quarter = 750ms, and triplet quarter = 333.33ms.
How do I set pre-delay for reverb based on tempo?
Pre-delay is the time gap between the original sound and the onset of reverb reflections, and it plays a critical role in maintaining clarity in a mix. Setting pre-delay to a tempo-synced value ensures the reverb tail starts at a musically logical moment. A common approach is to use a 1/64 note or 1/32 note value for the pre-delay, which creates enough separation for the direct sound to be perceived clearly before the reverb begins. For a song at 120 BPM, this translates to approximately 31ms or 62ms respectively. Shorter pre-delays (under 20ms) make the sound feel intimate and close, while longer pre-delays (40-80ms) create a sense of spaciousness while keeping the source sound distinct and articulate.
What is the relationship between delay time and frequency in Hz?
Delay time and frequency have an inverse relationship: Frequency (Hz) = 1000 / Delay Time (ms). This relationship becomes important when using very short delay times that enter the realm of audio-rate modulation. For example, a 10ms delay corresponds to 100 Hz, and a 1ms delay corresponds to 1000 Hz. When delay times drop below about 30ms, the individual echoes are no longer perceived as separate events but instead create comb filtering effects, where certain frequencies are reinforced and others are cancelled based on the delay time. Flanger and chorus effects exploit this principle by using very short, modulated delay times. Understanding this frequency relationship helps producers avoid unintentional comb filtering while enabling creative use of these effects.
How do I calculate delay times for polyrhythmic patterns?
Polyrhythmic delay patterns are created by setting multiple delay taps to different but mathematically related subdivisions. A common polyrhythmic combination is setting one delay to a quarter note and another to a dotted eighth note, which creates a 3-against-4 pattern. Another popular approach is combining eighth note and triplet eighth note delays. To calculate these, first determine the quarter note duration (60000 / BPM), then multiply by the appropriate factors for each subdivision. At 120 BPM: quarter = 500ms, dotted eighth = 375ms, triplet eighth = 166.67ms. Some producers also use prime number relationships for more complex patterns, such as delays set to 3/16 and 5/16 note values, creating patterns that take many beats to cycle back to their starting alignment.
What is tap tempo and how does it relate to delay time calculation?
Tap tempo is a feature that lets you set delay time by physically tapping a button in rhythm with the music, rather than manually entering a millisecond value. The system measures the time interval between your taps, averages several consecutive intervals for accuracy, and sets the delay time accordingly. This is especially useful for live performance situations where the exact BPM may be unknown or fluctuating. The mathematical relationship is the same as the delay time formula: the interval between taps in milliseconds directly represents a quarter note delay time. Many hardware delay pedals and rack units feature a dedicated tap tempo button. In studio production, knowing the exact BPM and using a calculator is more precise, but tap tempo remains invaluable for matching delays to recordings with tempo variations or for quickly dialing in a feel during creative sessions.