Sound - General

Sound - General

from Ching Viz Dictionary of Architecture

Hearing = the sense by which sound is perceived involving the entire mechanism of the internal, middle and external ear and including the nearvous and cerebral operations that translate the physical operations into meaningful signs.

Decibel = A unit for expressing the relative pressure or intensity of sounds on a uniform scale from 0 for the least perceptible sound to about 130 for the average threshold of pain. abbr. dB

Decibel levels of two sound sources cannot be added mathematically

loudness = a subjective response to sound indicating the magnitude of the auditory sensation produced by the amplitude of a sound wave.

phon = a unit for measuring the apparent loudness of a sound, equal in number to the decibels of a 1000-hz reference sound judged by a group of listeners to be equal in loudness to the given sound.

sone = a unit for measuring the apparent loudness of a sound, judged by a group of listeners to be equal to the loudness of a 1000-hz reference sound having an intensity of 40 decibels

Audio frequency = a range of frequencies from 15 Hz to 20,000 Hz audible to the normal human ear.

auditory fatigue = physical or mental weariness caused by prolonged exposure to loud noises.

sound power = the amount of acoustic energy radiated by a source per unit time, expressed in watts.

sound power level = teh acoustic power of a source measured on the decibel scale, equal to 10 times the common logarithm of the ratio of the acoustic power to a reference power, usually 10 to the negative 12th power watts.

sound pressure = the difference between the actual pressure at any point in the field of a sound wave and the static pressure at that point, expressed in pascals.

sound pressure level = sound pressure measured on the decibel scale, equal to 10 times the common logarithm of the ratio of the sound pressure to a reference pressure, usually 20 micropascals

sound intensity = the rate at which acoustic energy flows through a medium, expressed in watts per square meter.

sound intensity level = sound intensity measured on the decibel scale, equal to 10 times the common logarithm of the ratio of the sound intensity to a reference intensity, usually 10 to the negative 12th power watts per square meter.

logarithm = the exponent indicating the power to which a base number must be raised to arrive at a given number.

common logarithm = a logarithm having a base of 10.