AskDefine | Define noise

Dictionary Definition

noise

Noun

1 sound of any kind (especially unintelligible or dissonant sound); "he enjoyed the street noises"; "they heard indistinct noises of people talking"; "during the firework display that ended the gala the noise reached 98 decibels"
2 the auditory experience of sound that lacks musical quality; sound that is a disagreeable auditory experience; "modern music is just noise to me" [syn: dissonance, racket]
3 electrical or acoustic activity that can disturb communication [syn: interference, disturbance]
4 a loud outcry of protest or complaint; "the announcement of the election recount caused a lot of noise"; "whatever it was he didn't like it and he was going to let them know by making as loud a noise as he could"
5 incomprehensibility resulting from irrelevant information or meaningless facts or remarks; "all the noise in his speech concealed the fact that he didn't have anything to say"
6 the quality of lacking any predictable order or plan [syn: randomness, haphazardness, stochasticity] v : emit a noise [syn: make noise, resound]

User Contributed Dictionary

English

Pronunciation

Noun

  1. Various sounds, usually unwanted.
    He knew that it was trash day, when the garbage collectors made all the noise.
  2. Sound or signal generated by random fluctuations
  3. Unwanted part of a signal. (Signal to noise ratio)
  4. The measured level of variation in gene expression among cells, regardless of source, within a supposedly identical population

References

(Genetics meaning) "Noise in Gene Expression: Origins, Consequences, and Control." Jonathan M. Raser and Erin K. O'Shea (2005). Science. 309(5743):2010-2013.

Translations

various sounds, usually unwanted
sound or signal generated by random fluctuations
(techn.) Unwanted part of a signal. (Signal to noise ratio)
(genetics) The measured level of variation in gene expression among cells, regardless of source, within a supposedly identical population

Extensive Definition

In common use, the word noise means unwanted sound or noise pollution. In electronics noise can refer to the electronic signal corresponding to acoustic noise (in an audio system) or the electronic signal corresponding to the (visual) noise commonly seen as 'snow' on a degraded television or video image. In signal processing or computing it can be considered data without meaning; that is, data that is not being used to transmit a signal, but is simply produced as an unwanted by-product of other activities. In Information Theory, however, noise is still considered to be information. In a broader sense, film grain or even advertisements in web pages can be considered noise.
Noise can block, distort, or change the meaning of a message in both human and electronic communication.
In many of these areas, the special case of thermal noise arises, which sets a fundamental lower limit to what can be measured or signaled and is related to basic physical processes at the molecular level described by well-established thermodynamics considerations, some of which are expressible by relatively well known simple formulae.

Acoustic noise

When speaking of noise in relation to sound, what is commonly meant is meaningless sound of greater than usual volume. Thus, a loud activity may be referred to as noisy. However, conversations of other people may be called noise for people not involved in any of them, and noise can be any unwanted sound such as the noise of dogs barking, neighbours playing loud music, road traffic sounds, chainsaws, or aircraft, spoiling the quiet of the countryside.
For film sound theorists and practitioners at the advent of talkies c.1928/1929, noise was non-speech sound or natural sound and for many of them noise (especially asynchronous use with image) was desired over the evils of dialogue synchronized to moving image. The director and critic René Clair writing in 1929 makes a clear distinction between film dialogue and film noise and very clearly suggests that noise can have meaning and be interpreted: "...it is possible that an interpretation of noises may have more of a future in it. Sound cartoons, using "real" noises, seem to point to interesting possibilities" ('The Art of Sound' (1929)). Alberto Cavalcanti uses noise as a synonym for natural sound ('Sound in Films' (1939)) and as late as 1960, Siegfried Kracauer was referring to noise as non-speech sound ('Dialogue and Sound' (1960)).

Audio noise

In audio, recording, and broadcast systems audio noise refers to the residual low level sound (usually hiss and hum) that is heard in quiet periods of programme.
In audio engineering it can also refer to the unwanted residual electronic noise signal that gives rise to acoustic noise heard as 'hiss'. This signal noise is commonly measured using A-weighting or ITU-R 468 weighting

Electronic noise

Electronic noise exists in all circuits and devices as a result of thermal noise, also referred to as Johnson Noise. Semiconductor devices can also contribute flicker noise and generation-recombination noise. In any electronic circuit, there exist random variations in current or voltage caused by the random movement of the electrons carrying the current as they are jolted around by thermal energy. Lower temperature results in lower thermal noise. This same phenomenon limits the minimum signal level that any radio receiver can usefully respond to, because there will always be a small but significant amount of thermal noise arising in its input circuits. This is why radio telescopes, which search for very low levels of signal from stars, use front-end low-noise amplifier circuits, usually mounted on the aerial dish, and cooled with liquid nitrogen.

See also

noise in Afrikaans: Geraas
noise in Catalan: Soroll
noise in Czech: Hluk
noise in Danish: Støj
noise in German: Geräusch
noise in Spanish: Ruido (sonido)
noise in Esperanto: Bruo
noise in French: Bruit
noise in Hebrew: רעש
noise in Indonesian: derau
noise in Italian: Rumore (acustica)
noise in Lithuanian: Triukšmas
noise in Dutch: Ruis (signaal)
noise in Japanese: ノイズ
noise in Norwegian: Støy
noise in Norwegian Nynorsk: Støy
noise in Polish: Szum (sygnał)
noise in Portuguese: Ruído
noise in Russian: Шум
noise in Simple English: Noise
noise in Slovak: Hluk
noise in Slovenian: Šum
noise in Finnish: Melu
noise in Swedish: Brus
noise in Ukrainian: Шум
noise in Chinese: 噪声

Synonyms, Antonyms and Related Words

ALGOL, Aesopian language, Babel, Bedlam let loose, COBOL, EDP, FORTRAN, Greek, aimlessness, alphabetic data, alphanumeric code, amplitude, angular data, argot, assembler, atmospherics, auditory effect, auditory phenomenon, babble, babel, ballyhoo, bawling, be noisy, bedlam, binary digit, binary scale, binary system, bit, black spot, blare, blaring, blast, blasting, blind spot, bloom, blooping, bobbery, brawl, brouhaha, bruit about, bug, byte, cacophony, cant, channel, charivari, chirm, cipher, circulate, clamor, clangor, clap, clash, clatter, code, command pulses, commands, commotion, communication explosion, communication theory, compiler, computer code, computer language, computer program, confusion of tongues, control signals, controlled quantity, correcting signals, crash, crawling, creeping, cryptogram, data, data retrieval, data storage, dead letter, decoding, definition, din, discord, discordance, dissonance, disturbance, donnybrook, double Dutch, drift, drunken brawl, dustup, electronic data processing, emit a sound, emptiness, empty sound, encoding, entropy, error, error signals, fade-out, fading, feedback pulses, feedback signals, film data, flap, flare, fracas, free-for-all, fringe area, futility, garble, ghost, gibberish, gift of tongues, glossolalia, gobbledygook, granulation, grid, hard shadow, harshness, hell, hell broke loose, hexadecimal system, howl, hubbub, hue and cry, hullabaloo, image, inanity, information, information explosion, information theory, input data, input quantity, insignificance, instructions, interference, jangle, jar, jargon, jumble, loud noise, loudness, machine language, maffick, make a noise, make a racket, make a sound, make an uproar, meaninglessness, mere noise, message, multiple image, multiple messages, noise and shouting, nonsensicality, nullity, numeric data, octal system, oscillograph data, outcry, output data, output quantity, pandemonium, phatic communion, phone, picture, picture noise, picture shifts, play, polar data, punch-card data, purposelessness, racket, rain, raise Cain, raise a clamor, raise hell, raise the devil, raise the roof, random data, rattle, reception, rectangular data, redundancy, reference quantity, resound, rhubarb, roar, rolling, row, ruckus, ruction, ruly English, rumble, rumbling, rumor, rumpus, scanning pattern, scintillation, scramble, secret language, senselessness, shading, shindy, shivaree, signal, signals, single messages, slang, snow, snowstorm, sonance, sound, sound intensity level, sound propagation, sound wave, speak, speech sound, spread, static, thunder, thunderclap, thundering, tintamarre, tumult, turmoil, ultrasound, unmeaningness, unorganized data, unsignificancy, uproar, visible-speech data, whoop it up
Privacy Policy, About Us, Terms and Conditions, Contact Us
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2
Material from Wikipedia, Wiktionary, Dict
Valid HTML 4.01 Strict, Valid CSS Level 2.1