a subjective unit for loudness equal to the sound pressure level in decibels when compared to an equally loud standard note
a unit of volume that roughly corresponds with dB SPL
The unit of subjective sound level. Defined such that the sound level in phones equals the level in SPL for a 1000 Hz tone. Generally used in tests where listeners are asked when a tone at a different frequency sounds as loud as a 1000 Hz tone, to define the subjective frequency response of the ear. See discussion in the text on music and ears.
Loudness contours. A subjective impression of equal loudness by listeners as a function of frequency and sound level (dB). An increase in low frequency sound will be perceived as being much louder than an equivalent high frequency increase.
In acoustics, a unit of subjective loudness level equal to the sound pressure level in dB compared to that of an equally loud standard sound.
A unit of apparent loudness, equal in number to the intensity in decibels of a 1,000 Hz tone judged to be as loud as the sound being measured.