Dictionary Definition
sone n : a unit of perceived loudness equal to
the loudness of a 1000-hertz tone at 40 dB above threshold
User Contributed Dictionary
Noun
Extensive Definition
The sone was proposed as a unit of
perceived loudness by S. Smith
Stevens in 1936. In acoustics, loudness is the
subjective
perception of sound
pressure. Although defined by Stevens as a unit, it is not one
of the SI units.
Such units meet the stringent criteria of metrology, which include being
realizable in a highly precise and reproducible manner, and so
transferable for scientific and industrial purposes in a range of
contexts.
According to Stevens' definition, the sone is
equivalent to 40 phons,
which is defined as the loudness level NL of a 1 kHz tone at 40 dB SPL.
The number of sones to a phon was chosen so that a doubling of the
number of sones sounds to the human ear like
a doubling of the loudness, which also
corresponds to increasing the sound
pressure level by approximately 10 dB, or increasing the mean
square sound pressure
by a factor 10. At frequencies other than 1 kHz, the measurement in
sones must be calibrated according to the frequency response of
human hearing,
which is a subjective process. The study of apparent loudness is
included in the topic of psychoacoustics and
employs methods of psychophysics.
To be fully precise, a measurement in sones must
be specified in terms of the optional suffix G, which means that
the loudness value is calculated from frequency groups, and by one
of the two suffixes D (for direct field or free field) or R (for
room field or diffuse field).
Examples of sound pressure, sound pressure levels, and loudness in sone
External links
sone in Czech: Son (akustika)
sone in German: Sone
sone in Spanish: Sonio
sone in French: Sone
sone in Italian: Sone
sone in Dutch: Sone
sone in Polish: Son