Audio Delay Time Calculator
The Big Rig Audio Delay Time Calculator helps live sound engineers quickly convert distance into milliseconds for speaker delay, front fills, delay towers, PA alignment and subwoofer timing.
Audio delay time calculator
Enter a distance to calculate the audio delay time.
This audio delay time calculator gives a time-of-flight delay estimate. For critical alignment, always verify with measurement software.
How to use it
- Measure the distance between your reference source and the speaker you want to delay.
- Enter the distance in metres or feet.
- Set the current air temperature.
- Add any known digital delay if required.
- Use the result in your speaker processor, console, amplifier DSP or playback system.
Best used for
- Delay speaker timing
- Front fill alignment
- Out fill and side fill timing
- Subwoofer time-of-flight checks
- Live sound system setup
Speaker delay calculator
Use the distance from the main PA reference point to your delay speaker position to estimate the required delay time.
Front fill delay
Use delay to help front fills arrive with the main system instead of pulling the image down to the stage lip.
Subwoofer alignment
This tool calculates time of flight. Sub alignment also depends on phase, polarity, filters and crossover behaviour.
How the audio delay time calculator works
Audio delay time is the amount of time it takes sound to travel through air. In live sound, delay is normally set in milliseconds so different speakers arrive at the listener at the correct time.
A simple rule of thumb is around 2.9 ms per metre or around 0.89 ms per foot at roughly 20°C. Air temperature changes the speed of sound, so this calculator adjusts the result based on the temperature you enter.
For precise system alignment and verification, measurement platforms such as Rational Acoustics Smaart are recommended.
Common delay time reference table
| Distance | Approx delay at 20°C | Typical use |
|---|---|---|
| 1 metre | 2.91 ms | Small speaker offset |
| 5 metres | 14.57 ms | Front fill timing |
| 10 metres | 29.15 ms | Fill or small delay speaker |
| 25 metres | 72.87 ms | Delay speaker / distributed PA |
| 50 metres | 145.75 ms | Large delay system |
More free live sound tools
Looking for more system engineering and live sound tools? Try these free Big Rig resources:
Audio delay time calculator FAQ
How do you calculate audio delay from distance?
Audio delay is calculated by dividing distance by the speed of sound, then converting the result into milliseconds. At around 20°C, sound travels at roughly 343 metres per second.
How many milliseconds is 1 metre of audio delay?
At roughly 20°C, 1 metre is about 2.9 milliseconds of delay. The exact value changes slightly with air temperature.
How many milliseconds is 1 foot of audio delay?
At roughly 20°C, 1 foot is about 0.89 milliseconds of delay.
Should I delay the main PA or the fill speakers?
In most live sound setups, fills and delay speakers are delayed to match the main PA arrival time at the listening position.
Can this calculator align subwoofers?
It can calculate time of flight, but subwoofer alignment also depends on phase, polarity, filters, crossover points and loudspeaker processing.