|
Search over 100 encyclopedias and dictionaries: |
Research categories | Follow us on Twitter |
Research categories
View all topics in the newsView all reference sources at Encyclopedia.com |
|||
amplifier
amplifier device that accepts a varying input signal and produces an output signal that varies in the same way as the input but has a larger amplitude. The input signal may be a current, a voltage, a mechanical motion, or any other signal; the output signal is usually of the same nature. The most common types of amplifiers are electronic and have transistors or electron tubes as their principal components. Electronic amplifiers are used in radio and television transmitters and receivers, audio and stereo systems, intercoms, and other consumer electronics devices. Amplifiers in their simplest form are built around a single transistor. In one type of single-transistor amplifier, known as a common-emitter circuit, a varying input voltage is fed to the base of the transistor, and the output appears at the transistor's collector; the ratio of the output voltage to the input voltage is called the voltage gain. For many purposes a single transistor does not provide sufficient gain, or amplification. In a cascade, or multistage, amplifier, the output of the first amplifying device (transistor) is fed as input to the second amplifying device, whose output is fed as input to the third, and so on until an adequate signal amplification has been achieved. In a device such as a radio receiver, several amplifiers boost a weak input signal until it is powerful enough to drive a speaker. Usually, multistage amplifiers are not made of discrete components, but are built as integrated circuits . Another less common group of electronic amplifiers use magnetic devices as their principal components. There are also many kinds of mechanical amplifiers, e.g., the power steering system of an automobile. See operational amplifier . |
|
|
Cite this article
"amplifier." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 12 Feb. 2012 <http://www.encyclopedia.com>. "amplifier." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 12, 2012). http://www.encyclopedia.com/doc/1E1-amplifie.html "amplifier." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 12, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-amplifie.html |
|
amplifier
am·pli·fi·er / ˈampləˌfīər/ • n. an electronic device for increasing the amplitude of electrical signals, used chiefly in sound reproduction. ∎ a device of this kind combined with a loudspeaker, used to amplify electric guitars and other musical instruments. |
|
|
Cite this article
"amplifier." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 12 Feb. 2012 <http://www.encyclopedia.com>. "amplifier." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (February 12, 2012). http://www.encyclopedia.com/doc/1O999-amplifier.html "amplifier." The Oxford Pocket Dictionary of Current English. 2009. Retrieved February 12, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-amplifier.html |
|
amplifier
amplifier. A piece of electrical equipment which ‘amplifies’, i.e. increases, the vol. of sound. Voltage-controlled amplifiers alter the vol. of the input signal. They can be used in electronic music in conjunction with voltage-controlled oscillators and filters and a kbd. to function as a monophonic mus. instr.
|
|
|
Cite this article
MICHAEL KENNEDY and JOYCE BOURNE. "amplifier." The Concise Oxford Dictionary of Music. 1996. Encyclopedia.com. 12 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL KENNEDY and JOYCE BOURNE. "amplifier." The Concise Oxford Dictionary of Music. 1996. Encyclopedia.com. (February 12, 2012). http://www.encyclopedia.com/doc/1O76-amplifier.html MICHAEL KENNEDY and JOYCE BOURNE. "amplifier." The Concise Oxford Dictionary of Music. 1996. Retrieved February 12, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O76-amplifier.html |
|
amplifier
amplifier An electronic circuit which is used to increase the strength of an ANALOGUE SIGNAL; without such a device the signal would eventually become so weak that it could not be detected. Amplifier technology is a very mature engineering technology.
|
|
|
Cite this article
DARREL INCE. "amplifier." A Dictionary of the Internet. 2001. Encyclopedia.com. 12 Feb. 2012 <http://www.encyclopedia.com>. DARREL INCE. "amplifier." A Dictionary of the Internet. 2001. Encyclopedia.com. (February 12, 2012). http://www.encyclopedia.com/doc/1O12-amplifier.html DARREL INCE. "amplifier." A Dictionary of the Internet. 2001. Retrieved February 12, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O12-amplifier.html |
|
amplifier
amplifier Device for changing the magnitude (size) of a signal, such as voltage or current, but not the way it varies. Amplifiers are used in radio and television transmitters and receivers, and in audio equipment. See also thermionics
|
|
|
Cite this article
"amplifier." World Encyclopedia. 2005. Encyclopedia.com. 12 Feb. 2012 <http://www.encyclopedia.com>. "amplifier." World Encyclopedia. 2005. Encyclopedia.com. (February 12, 2012). http://www.encyclopedia.com/doc/1O142-amplifier.html "amplifier." World Encyclopedia. 2005. Retrieved February 12, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-amplifier.html |
|
amplifier
amplifier
•sapphire • backfire • campfire
•shellfire • ceasefire • misfire • spitfire
•speechifier
•humidifier, solidifier
•modifier • codifier • amplifier
•vilifier
•mollifier, qualifier
•nullifier • magnifier • indemnifier
•signifier • personifier • unifier
•typifier • stupefier
•clarifier, scarifier
•terrifier, verifier
•gentrifier • glorifier • purifier
•classifier, pacifier
•specifier • intensifier • crucifier
•emulsifier • versifier
•gratifier, ratifier
•sanctifier • identifier • testifier
•prettifier • quantifier • fortifier
•beautifier • stultifier • justifier
•liquefier • wildfire • watchfire
•bonfire • crossfire • bushfire • gunfire
•surefire • lammergeier • multiplier
•outlier • Niemeyer • quagmire
•vampire • empire • occupier • umpire
•hairdryer • prophesier • satire
•Blantyre • saltire • haywire • tripwire
•retrochoir • underwire
|
|
|
Cite this article
"amplifier." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 12 Feb. 2012 <http://www.encyclopedia.com>. "amplifier." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (February 12, 2012). http://www.encyclopedia.com/doc/1O233-amplifier.html "amplifier." Oxford Dictionary of Rhymes. 2007. Retrieved February 12, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-amplifier.html |
|
|
Search over 100 encyclopedias and dictionaries:
HighBeam™ Research, Inc. © Copyright 2012. All rights reserved.
The Encyclopedia.com advertising network includes:
