Acoustic Path Phase Difference Calculator

Method, formula and assumptions

Delay = extra path / sound speed. Cycles = delaySeconds x frequency; phase lag = cycles x 360 degrees. Wrap phase into [-180, 180), keeping the full lag in a separate result.

Input definitions and supported units

• Extra path length (m): Measured or assumed numerical value, from 0 to 1000; zero is supported where the stated method permits it.
• Tone frequency (Hz): Measured or assumed numerical value, from 0.01 to 100000; must be positive.
• Assumed sound speed (m/s): Measured or assumed numerical value, from 100 to 500; must be positive.

Worked example with answer

At 1,000 Hz and 340 m/s, 0.17 m extra path adds 0.5 ms and 0.5 cycles: 180 degrees unwrapped, displayed as -180 degrees in the wrapped interval.

How to use the results

The wrapped value compares phase at a single tone, while the unwrapped value retains the true multi-cycle path delay. The sign convention represents lag magnitude before wrapping.

Results retain full precision internally and display up to four decimal places. Very small nonzero results use scientific notation rather than appearing as zero. Check the labels before comparing values across units.

Limitations and references

This excludes electronic phase shifts and dispersion. Matching a wrapped phase at one frequency does not establish broadband time alignment.

The method is a self-contained arithmetic, geometric or explicitly stated mathematical model. There are no imported tariffs, empirical presets or equipment specifications; measured values and allowances must come from your own process.

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