There is really no standard distance from the sound source where the sound pressure level (SPL) is measured.
Loudness is the perceived intensity of sound, measured in decibels (dB). Distance affects loudness by causing sound to decrease in intensity the further it travels, as sound waves disperse in all directions. The inverse square law states that the sound pressure level decreases by 6 dB for each doubling of distance from the sound source.
The loudness or volume of music is measured in decibels. Decibels are a unit used to quantify the intensity of sound.
The loudness of sound is typically measured in units called decibels (dB). This unit quantifies the intensity of sound waves perceived by the human ear. Sound level meters are commonly used to measure the loudness of sound in various environments.
Loudness level LN is measured in phons and the Loudness N is measured in sones. Scroll down to related links and use the fine converter "Loudness level and loudness".
Loudness is measured in decibels (dB), which quantify the intensity of sound. A sound level meter is typically used to measure loudness, with higher decibel values indicating louder sounds.
Units used to measure loudness are Sone (loudness N) and Phon (loudness level L). Scroll down to related links and look at "Loudness - Wikipedia" and "Sound level change and the change of the respective factor of volume and loudness"
The loudness of sound is measured using the "decibel" or "bel" unit.
Just like any other substance in existence, the magnitude of sound or loudness can also be measured. In this case, the standard unit of measurement for loudness is called decibels.
decibels
Loudness of sound is measured in decibels (dB) which quantifies the intensity or volume of a sound. Softness of sound is generally perceived subjectively and does not have a standardized unit of measurement, but is often described as quiet or faint.
The loudness of the radio was measured at a high decibel level by the council authorities.
Loudness or sound level is measured in units called decibels (dB).