History Main / FeedbackRule

* A downplayed example in the beginning of ''Film/DasBoot'', where a German soldier comes on stage at a bar and tests the mic which produces a slight feedback.
* Happens in ''Film/FourteenOhEight'' when a bookstore clerk grabs a mic to announce the hero's autograph session for that night.

* In Film/TheShawshankRedemption, protagonist Andy Dufresne finds himself into the warden's office, with access to a phonograph and the microphone for the prison's paging system. After putting Theatre/LeNozzeDiFigaro on the record player, Andy locks the door and turns on the microphone, which immediately begins to feedback.

* In ''Literature/TheStand'', Stu deals with this during his speech at the first public Free Zone meeting. He says they have to get used to technology again (most of Boulder still had no power but they had a generator set up for the meeting). Plus, Stu was also [[UnaccustomedAsIAmToPublicSpeaking nervous]].

* Played with in a Christmas Sketch of ''Series/DadsArmy'', the platoon are recording a Christmas message for radio and keep hitting the microphone. The audience doesn't hear the feedback but the poor sound technician does through his headphones.

* ''Series/MidsomerMurders'': In "[[Recap/MidsomerMurdersS15E1 The Dark Rider]]", Sarah Barnaby is plagued by feedback while attempting to narrate the Civil War reenactment. She keeps yelling at her sound engineer Andy to fix the problem.
* ''Series/DeathInParadise'': Loud feedback occurs when a prominent academic steps up to the microphone to open the literary festival in "The Secret of the Flame Tree". The author's assistant is seen adjusting the sound board to kill the feedback. The scene is later important as [[spoiler:it shows the assistant had the necessary technical skills to pull off the audio trickery that made the murder possible]].

* In a concert recorded in 1973 and first released in 1980 as the album ''Jim Croce Live: The Final Tour'', Music/JimCroce reacts to an instance of feedback by imitating the sound and saying, "Sounds like a great big om."

* In Season 2 episode 15 of ''{{WesternAnimation/Futurama}}'', Bender gets feedback setting up the microphone he has plugged into himself.

* ''Series/MidsomerMurders'': In "The Dark Rider", Sarah Barnaby is plagued by feedback while attempting to narrate the Civil War reenactment. She keeps yelling at her sound engineer Andy to fix the problem.

-->'''Ben Singer''', ''WebAnimation/DeathBattle'' gag reel

* During the climactic scene in Creator/BrianDePalma's ''Film/{{Carrie}}'', principal Morton and instructor Fromm tussle over the microphone about what to say during the crisis at the prom. The resulting microphone squeal brings them to Carrie's attention. She electrocutes them with the mic wiring.

* This happens in ''Film/CarryOnBehind'', when the Major his testing his caravan site public address system. At first, the sound from the loudspeakers is garbled; somebody puts their ear to it, and is startled by the feedback.

Microphones have been around since the 1870s, so they have become a familiar piece of technology. Yet, despite many technological developments since then, one problem plagues microphone users in Fictionland: feedback. This loud squeal or throbbing sound is so ubiquitous that Literature/EbertsGlossaryOfMovieTerms has a "Feedback Rule". It seems inevitable that someone using a microphone will be interrupted by this sound, particularly when first speaking into it.

The sound can be used in different ways. Sometimes a savvy character will do something on purpose to create this sound in order to get attention, such as whistling into the mic, moving it near a speaker, or performing a MicDrop. On a [[LiveAlbum live recording]] of musicians or other performers, its presence lends credence to the notion that the performance is somehow raw or uncut and thus more realistic or natural. In radio plays and some early animation, the feedback is an audible cue that a microphone is in use, a kind of [[ShowDontTell demonstrative sound effect]] that is helpful to the audience. Feedback can also serve to point up a speaker's inexperience with sound equipment (moving the mic too much and/or pointing it towards a nearby speaker [[TruthInTelevision being likely to result in this sound)]], and the audible ''faux pas'' is useful for indicating anxiety and [[PlayedForLaughs prompting laughter]]. By extention, it may serve as an audible indicator of general inexperience with public speaking or performance.

----

* In the ''Machinima/TeamFortress2'' short ''[[https://www.youtube.com/watch?v=GLlLQ3LmZWU Expiration Date,]]'' Scout privately turns to Spy for help earning the heart of Ms. Pauling. However, since Scout made fun of Spy earlier, Spy responds by activating the intercom and blowing into it to create the feedback squeal that alerts everyone else, making it clear that Scout will have to really swallow his pride for Spy's help.

* In ''WesternAnimation/ToyStory'', Woody gets feedback when he starts the meeting, so he tells the speaker for the toy microphone to step back.

* In ''Film/BeginAgain'', when Creator/KeiraKnightley's character plays guitar and sings on stage, there is a noticeable mic feedback at one point. It's questionable why because that part wasn't louder than others, it was probably added as a reassurance that this was indeed a live performance.

* In TheShawshankRedemption, protagonist Andy Dufresne finds himself into the warden's office, with access to a phonograph and the microphone for the prison's paging system. After putting LaNozzeDiFigaro on the record player, Andy locks the door and turns on the microphone, which immediately begins to feedback.

* A downplayed example in the beginning of ''Film/DasBoot'', where a German soldier comes on stage at a bar and tests the mic which produces a slight feedback.

* ''Film/TheCannonballRun'' has a delayed reaction. When Mr. Foyt takes the stand at the Friends of Nature meeting, the microphone behaves itself. Then it feeds back in the middle of his speech.
* Happens in ''Film/FourteenOhEight'' when a bookstore clerk grabs a mic to announce the hero's autograph session for that night.
* In ''Film/BeginAgain'', when Creator/KeiraKnightley's character plays guitar and sings on stage, there is a noticeable mic feedback at one point. It's questionable why because that part wasn't louder than others, it was probably added as a reassurance that this was indeed a live performance.

* In the ''Machinima/TeamFortress2'' short ''[[https://www.youtube.com/watch?v=GLlLQ3LmZWU Expiration Date]]'', Scout privately turns to Spy for help earning the heart of Ms. Pauling. However, since Scout made fun of Spy earlier, Spy responds by activating the intercom and blowing into it to create the feedback squeal that alerts everyone else, making it clear that Scout will have to really swallow his pride for Spy's help.

Microphones have been around since the 1870s, so they have become a familiar piece of technology. Yet despite many technological developments since then, one problem plagues microphone users in Fictionland: feedback. This loud squeal or throbbing sound is so ubiquitous that Literature/EbertsGlossaryOfMovieTerms has a "Feedback Rule". It seems inevitable that someone using a microphone will be interrupted by this sound, particularly when first speaking into it.

* On ''WesternAnimation/ToyStory'', Woody gets feedback when he starts the meeting, so he tells the speaker for the toy microphone to step back.
* In the ''WesternAnimation/ShaunTheSheep'' movie, the rooster crows through a megaphone and winces from the feedback.

* ''WesternAnimation/MyLittlePonyEquestriaGirlsRainbowRocks'':
** When Snips [[MicDrop drops the microphone]] at the end of his and Snails's rap, a loud feedback sound is heard, forcing all the Rainbooms to cover their ears. This doesn't gain the boys any point with the Principals.
** When Rainbow Dash is testing the microphone on the stage for the upcoming concert, on her second try Sunset Shimmer has unthinkingly raised the volume to the max, causing yet another ear-splitting feedback.
* On ''WesternAnimation/MyLittlePonyEquestriaGirlsFriendshipGames'', Principal Cinch tapping the microphone at the school party causes a loud feedback, covering the music and putting an end to the students dancing.

* In ''WesternAnimation/CatsDontDance'', Darla Dimple screams into a boom mic, "GET ME DOWN FROM THERE ''THIS INSTANT!!!''", which electrocutes the headphone-wearing technician on the other end.

* In the French comedy ''Park Benches'' (2009), a female clerk at the DIY market does an announcement over the speakers which, of course, is accompanied by some feedback.

* In Season 2 episode 15 of {{WesternAnimation/Futurama}}, Bender gets feedback setting up the microphone he has plugged into himself.

* Music/TheBeatles opened IFeelFine with a guitar feeding back, which many claim was the first deliberate recording of instrument feedback on a record. Creator/JohnLennon would later do this at the ending of the Live Peace in Toronto concert in 1969, closing the show with Creator/YokoOno singing "John John (Let's Hope For Peace)" to the feedback of electric guitars. The band exited the stage while the instruments continued to feedback, until their roadie turned their amplifiers off.

* BridgetJonesDiary: After a gag when Bridget has just given a speech for which she thought her microphone was not working, Mr Fitzherbert says "I'll just switch this on". Feedback is heard when he does so.

* Occurs in ''Film/Yesterday2019'' before Jack plays ''Help''.

* During the climactic scene in Creator/BrianDePalma's ''Film/{{Carrie}}'', principal Morton and instructor Fromm tussle over the microphone about what to say during the crisis at the prom. The resulting microphone squeal brings them to Carrie's attention; she disposes of these goofballs by electrocuting them with the mic wiring.

* During Hiro's speech in ''Disney/BigHero6'', the mic that he used gives a harsh feedback just after his introduction.