Noise: Perceived sounds not in the original soundtrack. Such things as hiss, crackle, pops, hum, and buzz, are typical of the types of extraneous signals described as noise. Inherent noise in the electronic processing in any sytem is measured in decibels relative to the amplitude of the original signal. Sounds perceived as noise are heard in contrast to the sound that is the object of attention. Thus, a noise signal measured at 15 decibels below the output of Tchaikovski's 1812 Overture finale would probably not even be heard; while a slight hiss at 55 db below the level of a soft piano passage would be annoyingly obvious. Generally, any piece of equipment which generates ambient noise of more than 90 db below the level of a typical audio signal is noise free as far as most human perception is concerned.

 

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Noise: Perceived sounds not in the original soundtrack. Such things as hiss, crackle, pops, hum, and buzz, are typical of the types of extraneous signals described as noise. Inherent noise in the e . . . View Full Definition

Signal To Noise Ratio: A measurement of noise level in a device compared to the level of the signal. Higher numbers signify a greater difference, which is better. In technical terms, it is the ratio, expressed in . . . View Full Definition

Noise Floor: Normally the lowest threshold of useful signal level (although sometimes audible signals below the noise floor may be recovered).

Pink Noise: Pink noise is a random noise source characterized by a flat amplitude response per octave band of frequency, i.e., it has equal energy, or constant power, per octave. Pink noise is created b . . . View Full Definition