The phon scale is a subjective measure of loudness, which is a fundamental aspect of sound perception. Developed in the 1930s by Stanley Smith Stevens, the phon scale is a logarithmic scale used to express the loudness of sounds in a way that correlates with human perception. This paper will provide an overview of the phon scale, its definition, applications, and limitations.
: By definition, the phon scale is set to be numerically equal to the sound pressure level in decibels at a frequency of 1 kHz . For example, a 1 kHz tone at 40 dB SPL has a loudness of 40 phons. phon scale
If you have a low bass note at 100 Hz and a mid-range tone at 1,000 Hz, and you want them to sound equally loud (e.g., 40 phons): The phon scale is a subjective measure of
The phon is not measured directly; it is derived through psychophysical experiments. : By definition, the phon scale is set
The human ear is most sensitive to frequencies between 2,000 Hz and 5,000 Hz (the range of human speech). It is much less sensitive to very low bass frequencies or extremely high treble frequencies.
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