Bel - Revision history

Speckmade at 17:53, 14 June 2007

2007-06-14T17:53:03Z

← Older revision		Revision as of 17:53, 14 June 2007
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	::<math>{di\! f\!\! f} = \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>		::<math>{di\! f\!\! f} = \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>

	In case of the ~~decibel~~ we have a ''10'' factor:		In case of the ''deci''bel we have a ''10'' factor:

	::<math>{di\! f\!\! f} = 10 \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>		::<math>{di\! f\!\! f} = 10 \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>

Speckmade: hope my adjustments are right

2007-06-14T17:52:30Z

hope my adjustments are right

← Older revision		Revision as of 17:52, 14 June 2007
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	The '''bel''' is a logarithmical unit used to express relative difference in intensity or power between two signals, usually acoustic. Because of the fact that the Bel unit is too large for everyday use most of the times it is used as the more convenient '''decibel''' (abbreviated to '''dB''').		The '''bel''' ('''B''') is a logarithmical unit used to express relative difference in intensity or power between two signals, usually acoustic. Because of the fact that the Bel unit is too large for everyday use most of the times it is used as the more convenient '''decibel''' (abbreviated to '''dB''').

	Decibel is equal to ten times the common logarithm of the ratio of the two levels.		Decibel is equal to ten times the common logarithm of the ratio of the two levels.
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	::<math>{di\! f\!\! f} = 2 \cdot \log_{10}\left(\frac{p_2}{p_1}\right )</math> because <math>\log_{10}(a^2) = 2 \cdot \log_{10}(a)</math>		::<math>{di\! f\!\! f} = 2 \cdot \log_{10}\left(\frac{p_2}{p_1}\right )</math> because <math>\log_{10}(a^2) = 2 \cdot \log_{10}(a)</math>

	In this scale, it means an increase of 20 dB is equal to a ten-fold ratio, or 6 dB a two-fold ratio (<math>20 \cdot \log_{10}(2)</math> ''is approximately equal to 6'').		In this scale, it means an increase of 20 B is equal to a ten-fold ratio, or 6 B a two-fold ratio (<math>2 \cdot \log_{10}(2)</math> ''is approximately equal to 6'').

	[[Category:Technical]]		[[Category:Technical]]

Speckmade at 17:33, 14 June 2007

2007-06-14T17:33:17Z

← Older revision		Revision as of 17:33, 14 June 2007
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	~~{{title\|~~dB}}		The '''bel''' is a logarithmical unit used to express relative difference in intensity or power between two signals, usually acoustic. Because of the fact that the Bel unit is too large for everyday use most of the times it is used as the more convenient '''decibel''' (abbreviated to '''dB''').

	~~The '''decibel''' (abbreviated to '''dB''')~~ is ~~a logarithmical unit used~~ to ~~express relative difference in intensity or power between~~ two ~~signals, usually acoustic~~.		Decibel is equal to ten times the common logarithm of the ratio of the two levels.

	~~It is equal to ten times the common logarithm of the ratio~~ of the ~~two levels.~~		::<math>{di\! f\!\! f} = \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>

			In case of the decibel we have a ''10'' factor:

	::<math>{di\! f\!\! f} = 10 \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>		::<math>{di\! f\!\! f} = 10 \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>

	~~The ''10'' factor comes from the fact the Bel unit is too large for everyday use; decibel is just more convenient.~~

	There is a second definition of the decibel. In acoustics, it is used to express the ratio in sound pressure, because power is roughly proportional to the square of effective sound pressure.		There is a second definition of the decibel. In acoustics, it is used to express the ratio in sound pressure, because power is roughly proportional to the square of effective sound pressure.
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	Let 'p' be pressure, 'P' power.		Let 'p' be pressure, 'P' power.

	::<math>{di\! f\!\! f} = 10 \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>		::<math>{di\! f\!\! f} = \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>

	::<math>{di\! f\!\! f} = 10 \cdot \log_{10}\left(\frac{p_2^2}{p_1^2}\right )</math>		::<math>{di\! f\!\! f} = \cdot \log_{10}\left(\frac{p_2^2}{p_1^2}\right )</math>

	::<math>{di\! f\!\! f} = 20 \cdot \log_{10}\left(\frac{p_2}{p_1}\right )</math> because <math>\log_{10}(a^2) = 2 \cdot \log_{10}(a)</math>		::<math>{di\! f\!\! f} = 2 \cdot \log_{10}\left(\frac{p_2}{p_1}\right )</math> because <math>\log_{10}(a^2) = 2 \cdot \log_{10}(a)</math>

	In this scale, it means an increase of 20 dB is equal to a ten-fold ratio, or 6 dB a two-fold ratio (<math>20 \cdot \log_{10}(2)</math> ''is approximately equal to 6'').		In this scale, it means an increase of 20 dB is equal to a ten-fold ratio, or 6 dB a two-fold ratio (<math>20 \cdot \log_{10}(2)</math> ''is approximately equal to 6'').

	[[Category:Technical]]		[[Category:Technical]]

Speckmade: DB moved to Bel

2007-06-14T17:20:18Z

DB moved to Bel

← Older revision	Revision as of 17:20, 14 June 2007
(No difference)

Pepoluan: wiki formatting and TeX formatting

2006-10-11T16:03:31Z

wiki formatting and TeX formatting

← Older revision		Revision as of 16:03, 11 October 2006
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	It is equal to ten times the common logarithm of the ratio of the two levels.		It is equal to ten times the common logarithm of the ratio of the two levels.

	<math>{~~diff~~} = 10 \cdot log_{10}\left(\frac{P_2}{P_1}\right )</math>		::<math>{di\! f\!\! f} = 10 \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>

	The ''10'' factor comes from the fact the Bel unit is too large for everyday use; decibel is just more convenient.		The ''10'' factor comes from the fact the Bel unit is too large for everyday use; decibel is just more convenient.
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	Let 'p' be pressure, 'P' power.		Let 'p' be pressure, 'P' power.
	<math>{~~diff~~} = 10 \cdot log_{10}\left(\frac{P_2}{P_1}\right )</math>
			::<math>{di\! f\!\! f} = 10 \cdot \log_{10}\left(\frac{P_2}{P_1}\right )</math>

	<math>{~~diff~~} = 10 \cdot log_{10}\left(\frac{p_2^2}{p_1^2}\right )</math>		::<math>{di\! f\!\! f} = 10 \cdot \log_{10}\left(\frac{p_2^2}{p_1^2}\right )</math>

	<math>{~~diff~~} = 20 \cdot log_{10}\left(\frac{p_2}{p_1}\right )</math> because <math>log_{10}(a^2) = 2 \cdot log_{10}(a)</math>		::<math>{di\! f\!\! f} = 20 \cdot \log_{10}\left(\frac{p_2}{p_1}\right )</math> because <math>\log_{10}(a^2) = 2 \cdot \log_{10}(a)</math>
	In this scale, it means an increase of 20 dB is equal to a ten-fold ratio, or 6 dB a two-fold ratio (<math>20 \cdot log_{10}(2)</math> ''is approximately equal to 6'').
			In this scale, it means an increase of 20 dB is equal to a ten-fold ratio, or 6 dB a two-fold ratio (<math>20 \cdot \log_{10}(2)</math> ''is approximately equal to 6'').

	[[Category:Technical]]		[[Category:Technical]]

Jan: Texified

2006-10-10T17:31:22Z

Texified

← Older revision		Revision as of 17:31, 10 October 2006
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	It is equal to ten times the common logarithm of the ratio of the two levels.		It is equal to ten times the common logarithm of the ratio of the two levels.
	diff = 10 ~~× log<sub>~~10~~</sub>~~(~~P<sub>2</sub> / P<sub>1~~</~~sub~~>)
			<math>{diff} = 10 \cdot log_{10}\left(\frac{P_2}{P_1}\right )</math>

	The ''10'' factor comes from the fact the Bel unit is too large for everyday use; decibel is just more convenient.		The ''10'' factor comes from the fact the Bel unit is too large for everyday use; decibel is just more convenient.
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	Let 'p' be pressure, 'P' power.		Let 'p' be pressure, 'P' power.
	diff = 10 ~~× log<sub>~~10~~</sub>~~(~~P<sub>2~~</~~sub~~> ~~/ P~~<~~sub~~>~~1</sub>)~~		<math>{diff} = 10 \cdot log_{10}\left(\frac{P_2}{P_1}\right )</math>

	diff = 10 ~~× log<sub>~~10~~</sub>~~(~~p<sub>~~2~~</sub><sup>~~2</~~sup~~> ~~/ p<sub>1</sub><sup>2~~<~~/sup~~>)		<math>{diff} = 10 \cdot log_{10}\left(\frac{p_2^2}{p_1^2}\right )</math>

	diff = 20 ~~× log<sub>~~10~~</sub>~~(~~p<sub>2~~</~~sub~~> ~~/ p<sub>1</sub>)~~ because ~~log~~<~~sub~~>10~~</sub>~~(a~~<sup>~~2~~</sup>~~) = 2 ~~× log<sub>~~10</~~sub~~>~~(a)~~		<math>{diff} = 20 \cdot log_{10}\left(\frac{p_2}{p_1}\right )</math> because <math>log_{10}(a^2) = 2 \cdot log_{10}(a)</math>
	In this scale, it means an increase of 20 dB is equal to a ten-fold ratio, or 6 dB a two-fold ratio (<tt>20 ~~× log<sub>~~10~~</sub>~~(2)</tt> ''is approximately equal to 6'').		In this scale, it means an increase of 20 dB is equal to a ten-fold ratio, or 6 dB a two-fold ratio (<math>20 \cdot log_{10}(2)</math> ''is approximately equal to 6'').


	[[Category:Technical]]		[[Category:Technical]]

RasqualTwilight: Expanded a bit

2006-10-10T11:48:00Z

Expanded a bit

@@ Line 1: / Line 1: @@
 {{title|dB}}
-'''Decibel''' (abbreviated to '''dB''') is a unit used to express relative difference in intensity or power, usually between two acoustic signals, equal to ten times the common logarithm of the ratio of the two levels.
+The '''decibel''' (abbreviated to '''dB''') is a logarithmical unit used to express relative difference in intensity or power between two signals, usually acoustic.
 [[Category:Technical]]

Pepoluan: dB abbreviation

2006-10-09T18:36:53Z

dB abbreviation

← Older revision		Revision as of 18:36, 9 October 2006
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	{{title\|dB}}		{{title\|dB}}

	'''Decibel''' is a unit used to express relative difference in intensity or power, usually between two acoustic signals, equal to ten times the common logarithm of the ratio of the two levels.		'''Decibel''' (abbreviated to '''dB''') is a unit used to express relative difference in intensity or power, usually between two acoustic signals, equal to ten times the common logarithm of the ratio of the two levels.

	[[Category:Technical]]		[[Category:Technical]]

Pepoluan: Destroy link to database

2006-10-02T21:37:50Z

Destroy link to database

← Older revision		Revision as of 21:37, 2 October 2006
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	{{title\|dB}}		{{title\|dB}}
	~~''See [[database]] if you wanted the abbreviation.''~~

	Decibel is a unit used to express relative difference in intensity or power, usually between two acoustic signals, equal to ten times the common logarithm of the ratio of the two levels.		'''Decibel''' is a unit used to express relative difference in intensity or power, usually between two acoustic signals, equal to ten times the common logarithm of the ratio of the two levels.

	[[Category:Technical]]		[[Category:Technical]]

Elliottmobile at 14:19, 30 September 2006

2006-09-30T14:19:55Z

← Older revision		Revision as of 14:19, 30 September 2006
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	{{title\|dB}}		{{title\|dB}}
	''See [[database]] if you wanted the abbreviation.''		''See [[database]] if you wanted the abbreviation.''

	Decibel is a unit used to express relative difference in intensity or power, usually between two acoustic signals, equal to ten times the common logarithm of the ratio of the two levels.		Decibel is a unit used to express relative difference in intensity or power, usually between two acoustic signals, equal to ten times the common logarithm of the ratio of the two levels.

	[[Category:Technical]]		[[Category:Technical]]