Loudness
Definition
The perceived intensity of a sound, which correlates with — but is not identical to — level or amplitude. Influenced by frequency content, dynamics, duration, and the psychoacoustic response of human hearing.
In Simple Terms
How loud something actually sounds to your ears — not what the meter says. A heavily compressed track might measure the same as a dynamic one but feel louder because it's dense and constant. Loudness is perception, not just numbers.
In Practice
A heavily compressed track may measure louder on a peak meter but feel less engaging than a more dynamic track at the same average loudness, because the constant density causes ear fatigue.
Sources & Verification
- ITU-R BS.1770-4 — Algorithms to measure audio programme loudness and true-peak audio levelInternational Telecommunication Union, 2015
- Fletcher, H. & Munson, W. A. — Loudness, Its Definition, Measurement and CalculationJournal of the Acoustical Society of America, 1933
- Moore, B. C. J. — An Introduction to the Psychology of Hearing (6th ed.)Brill, 2012
Last verified: 2026-05-05