The purpose of the phon is to provide a logarithmic measurement (like decibels) for perceived sound magnitude, while the primary loudness standard methods result in a linear representation.

Using the rule of thumb for loudness, the sone scale was created to provide such a linear scale of loudness. It is usually presumed that the standard range for orchestral music is about 40 to 100 phons.

A unit of loudness, called the phon, has been established. The number of phons of any given sound is equal to the number of decibel s of a pure 1,000-hertz tone judged by the listener to be equally loud.

PHON definition: a unit for measuring the apparent loudness of a sound, equal in number for a given sound to the intensity in decibels of a sound having a frequency of 1000 cycles per second when, in …

A unit of apparent loudness, equal in number to the intensity in decibels of a 1,000-hertz tone perceived to be as loud as the sound being measured....

phon in American English (fɑn) noun a unit for measuring the apparent loudness of a sound, equal in number for a given sound to the intensity in decibels of a sound having a frequency of 1000 cycles …

A phon is a unit of perceived loudness level for pure tones. It is numerically equal to the sound pressure level in decibels (dB) of a 1 kHz tone that is perceived as equally loud.

Dec 23, 2025 · The loudness in phons of a sound is defined as the intensity level in units of decibel sound pressure level (dB SPL) of a comparison pure tone of 1,000 hertz that is judged by the listener …

Oct 3, 2025 · phon (plural phons) (acoustics) A unit of apparent loudness, equal in number to the intensity in decibels of a 1,000-hertz tone judged to be as loud as the sound being measured.

Phon definition: A measure of the apparent loudness level of a sound with respect to a 1,000-cycle-per-second pure tone: based on the subjective judgment of the human ear or on objective comparisons …