decibel

decibel
One-tenth of a bel; unit for expressing the relative intensity of sound on a logarithmic scale. [L. decimus, tenth, + bel]

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deci·bel 'des-ə-bəl, -.bel n
1 a) a unit for expressing the ratio of two amounts of electric or acoustic signal power equal to 10 times the common logarithm of this ratio
b) a unit for expressing the ratio of the magnitudes of two electric voltages or currents or analogous acoustic quantities equal to 20 times the common logarithm of the voltage or current ratio
2) a unit for expressing the relative intensity of sounds on a scale from zero for the average least perceptible sound to about 130 for the average pain level

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n.
one tenth of a bel: a unit for comparing levels of power (especially sound) on a logarithmic scale. A power source of intensity P has a power level of 10 log10 P/P0 decibels, where P0 is the intensity of a reference source. The decibel is much more widely used than the bel. Silence is 0 dB; a whisper has an intensity of 30 dB, normal speech 60 dB, a shout 90 dB, and a jet aircraft 120 dB.

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dec·i·bel (desґĭ-bəl) a unit of relative power intensity equal to one tenth of a bel, used for electric or acoustic power measurements. The decibel level is ten times the base ten logarithm of the ratio of the measured power to some reference power level. A one decibel change is an increase in the power level by a factor of 1.26, approximately the smallest change in sound level detectable by human ears; a ten decibel (one bel) change multiplies the power by a factor of ten and approximately doubles the perceived sound level. In audiometry the reference power level (0 db) corresponds to a root-mean-square sound pressure level of 2 Ч 10−4 dyn/cm2, which is approximately the threshold of hearing for healthy young persons. Symbol, dB.

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  • Decibel — Décibel Pour les articles homonymes, voir Décibel (homonymie). Le décibel (dB) est une unité logarithmique de mesure du rapport entre deux puissances. C’est une grandeur sans dimension en dehors du système international[1]. Elle est utilisée… …   Wikipédia en Français

  • Decibel — Basisdaten Entwickler KDE / supported by NLNet and basysKom Aktuelle Version …   Deutsch Wikipedia

  • décibel — [ desibɛl ] n. m. • 1932; de déci et 2. bel 1 ♦ Métrol. Unité, égale au dixième du bel, servant à exprimer le rapport de deux puissances (acoustiques, électriques, etc.), notamment d une puissance donnée par rapport à une puissance de référence… …   Encyclopédie Universelle

  • decibel — DECIBÉL, decibeli, s.m. Unitate de măsură a intensităţii sonore, egală cu o zecime dintr un bel. – Din fr. décibel. Trimis de dante, 13.09.2007. Sursa: DEX 98  decibél s. m., pl. decibéli; simb. dB Trimis de siveco, 10.08.2004. Sursa: Dicţionar… …   Dicționar Român

  • Decibel — Saltar a navegación, búsqueda Decibel puede referirse a: decibelio en inglés, nombre de la unidad de comparación de magnitudes; a la rock progresivo y del rock en oposición, a Decibel, el framework de comunicaciones en tiempo real de KDE 4.… …   Wikipedia Español

  • dècibel — m 1. {{001f}}fiz. jedinica za mjerenje razlika u snazi (simbol dB), najčešće u elektronici; u akustici mjeri razlike u pritiscima u mediju koji prenosi zvuk (jedan decibel je približno najmanja razlika intenziteta zvuka koju može zamijetiti… …   Veliki rječnik hrvatskoga jezika

  • decibel — 1928, from DECI (Cf. deci ) + BEL (Cf. bel) (n.) …   Etymology dictionary

  • decibel — s. m. Décima parte do bel, unidade de medida que serve, em acústica, para definir uma escala de intensidade sonora (símbolo: dB). [A voz média tem por intensidade 55 dB.] …   Dicionário da Língua Portuguesa

  • decibel — o decibelio sustantivo masculino 1. Área: física Unidad que se utiliza para medir la intensidad de un sonido …   Diccionario Salamanca de la Lengua Española

  • decibel — m. Fís. decibelio …   Diccionario de la lengua española

  • decibel — ► NOUN ▪ a unit of measurement expressing the intensity of a sound or the power of an electrical signal. ORIGIN from DECI (Cf. ↑deci ) + bel, a unit (= 10 decibels) named after Alexander Graham Bell (1847 1922), inventor of the telephone …   English terms dictionary

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