Speaker Delay Calculator
Sound takes about three milliseconds to travel a metre, which is why a speaker at the back of a room must be delayed to match the stage. Get it wrong and the audience hears the near speaker first, so the whole event seems to come from behind them. A small extra delay on top is deliberate: arriving very slightly second keeps everyone's sense of direction pointing at the stage.
What this generator does
Divides the distance by the speed of sound at your temperature to get the travel time, then adds the Haas offset you choose, giving the figure to enter on the delay speaker.
How to use this tool
- Enter how far the delay speaker is behind the main system.
- Set the temperature — it changes the speed of sound more than people expect.
- Add the Haas offset, usually between ten and twenty milliseconds.
- Use the total figure on the delay speaker's processor.
Understanding the controls
- Distance behind
- How far the delay speaker sits behind the main system, in metres. This is the distance sound has to cover, not the distance to the audience.
- Temperature
- Sound gains about 0.6 m/s per degree, so a rig set at dawn is measurably wrong by mid-afternoon — which is why outdoor systems get re-timed.
- Haas offset
- Extra delay on top, usually ten to twenty milliseconds. It makes the far speaker arrive just after the stage, so listeners still localise the sound forwards.
Common use cases
- Time-aligning delay speakers in a hall or marquee
- Setting up an outdoor system where temperature shifts through the day
- Understanding why a distant speaker sounds wrong without delay
- Teaching how sound propagation affects live audio
- Checking a figure from a processor against first principles
How this generator works
The check runs the relation backwards: the reported delay multiplied by the speed of sound must recover the distance you entered. It also confirms the relationship is monotonic in temperature — warmer air must give a faster speed — which catches a sign error that recomputing alone would miss.
Randomness and fairness
Nothing here is random. The delay follows entirely from the distance and temperature you enter.
For how randomness is produced across the whole site, see how Generate Random works.
Limitations and good to know
- Dry air is assumed. Humidity changes the speed slightly, though far less than temperature does.
- A single delay ring. Large systems have several, each timed to the one before it rather than to the stage.
- Says nothing about level, coverage or the crossover behaviour that matters just as much in practice.
- Wind moves the air itself, which can shift arrival times outdoors more than any of this.
Privacy and your data
Distances, temperatures and offsets stay in your browser. No delay figure is transmitted or stored.
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