Editing Resonator (section)

== Acoustic ==
{{main|Acoustic resonance}}

The most familiar examples of acoustic resonators are in [[musical instrument]]s.  Every musical instrument has resonators.  Some generate the sound directly, such as the wooden bars in a [[xylophone]], the head of a [[drum]], the strings in [[stringed instrument]]s, and the pipes in an [[organ (instrument)|organ]].  Some modify the sound by enhancing particular frequencies, such as the [[sound box]] of a [[guitar]] or [[violin]].  [[Organ pipe]]s, the bodies of [[woodwind]]s, and the sound boxes of stringed instruments are examples of acoustic cavity resonators.

===Automobiles===
[[File:Exhaust with Resonator.jpg|right|thumb|A sport motorcycle, equipped with exhaust resonator, designed for performance]]
The exhaust pipes in automobile [[exhaust system]]s are designed as acoustic resonators that work with the [[muffler]] to reduce noise, by making sound waves "cancel each other out".<ref>{{cite web|url=http://auto.howstuffworks.com/muffler4.htm|title=How Mufflers Work|date=19 February 2001|website=howstuffworks.com|access-date=7 May 2018|url-status=live|archive-url=http://archive.wikiwix.com/cache/20051008174400/http://auto.howstuffworks.com/muffler4.htm|archive-date=8 October 2005}}</ref> The "exhaust note" is an important feature for some vehicle owners, so both the original manufacturers and the [[aftermarket (automotive)|after-market suppliers]] use the resonator to enhance the sound.  In "[[tuned exhaust]]" systems designed for performance, the resonance of the exhaust pipes can also be used to remove combustion products from the combustion chamber at a particular engine speed or range of speeds.<ref>{{cite book|title=Advanced Automotive Technology|page=84|publisher=United States [[Office of Technology Assessment]]|date=September 1995|url=http://www.princeton.edu/~ota/disk1/1995/9514_n.html}}.</ref>

=== Percussion instruments ===

In many [[keyboard percussion]] instruments, below the centre of each note is a tube, which is an [[Acoustic resonance|acoustic cavity resonator]]. The length of the tube varies according to the pitch of the note, with higher notes having shorter resonators. The tube is open at the top end and closed at the bottom end, creating a column of air that [[resonance|resonates]] when the note is struck. This adds depth and volume to the note. In string instruments, the body of the instrument is a resonator. The [[tremolo]] effect of a [[vibraphone]] is achieved via a mechanism that opens and shuts the resonators.

=== Stringed instruments ===
[[File:Steel guitar-KayEss.1.jpeg|thumb|upright|A [[Dobro]]-style [[resonator guitar]]]]
String instruments such as the bluegrass [[banjo]] may also have resonators. Many five-string banjos have removable resonators, so players can use the instrument with a resonator in [[Bluegrass music|bluegrass]] style, or without it in [[folk music]] style. The term ''resonator'', used by itself, may also refer to the [[resonator guitar]].

The modern [[ten-string guitar]], invented by [[Narciso Yepes]], adds four sympathetic string resonators to the traditional classical guitar. By tuning these resonators in a very specific way (C, B♭, A♭, G♭) and making use of their strongest partials (corresponding to the octaves and fifths of the strings' fundamental tones), the bass strings of the guitar now resonate equally with any of the 12 tones of the chromatic octave. The [[EBow|guitar resonator]] is a device for driving guitar string harmonics by an electromagnetic field. This resonance effect is caused by a feedback loop and is applied to drive the fundamental tones, octaves, 5th, 3rd to an infinite [[sustain]].