STILL / FIELD NOTES 06

Leq, maximum and peak: three different questions

Leq represents the steady level with the same sound energy over a specified interval. Maximum records the highest value of a time-weighted level during that interval. Peak describes a different, very brief pressure extreme. They should not be substituted for one another.

September 8, 2026 · Arve Tech, maker of Still

Always include the interval

An average from a short burst and an average from a long session answer different questions. Include measurement duration, units and weighting when quoting a result. If your input is unadjusted dBFS, the result remains a digital-level summary rather than calibrated environmental SPL.

Do not average decibel numbers casually

Because decibels are logarithmic, an arithmetic average of displayed levels is generally not an energy average. Equal-duration levels of 60 and 70 dB produce an energy average of about 67.4 dB, not 65 dB. This example assumes comparable quantities and settings.

Try a repeatable approach

1. Decide whether typical energy or a short extreme matters to the question.
2. Keep the metric name and time interval in the report.
3. Compare the same metric under the same configuration.

Source and scope

Brüel & Kjær: environmental noise measurement handbook

Measurement guidance is educational. Still is not a certified sound level meter and does not establish medical, legal or workplace-compliance conclusions. App-specific statements describe version 1.0.0, currently awaiting App Store review.