Pitch shifting#Pitch shifter and harmonizer

The simplest methods are used to increase pitch and reduce durations or, conversely, reduce pitch and increase duration. This can be done by replaying a sound waveform at a different speed than it was recorded. It could be accomplished on an early reel-to-reel tape recorder by changing the diameter of the capstan or using a different motor. As for vinyl records, placing a finger on the turntable to give friction will slow it, while giving it a "spin" can advance it. As technologies improved, motor speed and pitch control could be achieved electronically by servo drive system circuits.{{Cite web |url=http://artsites.ucsc.edu/EMS/music/equipment/analog_recorders/analog_recorders.html |title=Analog Tape Recorders |publisher=UCSC Electronic music studios 1996 |access-date=15 February 2011}}

{{redirect|Harmonizer|3=Harmonizers (disambiguation)}}

A pitch shifter is a sound effects unit that raises or lowers the pitch of an audio signal by a preset interval. For example, a pitch shifter set to increase the pitch by a fourth will raise each note three diatonic intervals above the notes actually played. Simple pitch shifters raise or lower the pitch by one or two octaves, while more sophisticated devices offer a range of interval alterations. Pitch shifters are included in most audio processors today.

A harmonizer is a type of pitch shifter that combines the pitch-shifted signal with the original to create a two or more note harmony. The Eventide H910 Harmonizer,{{Cite web|url=https://www.eventideaudio.com/blog/aagnello/50th-flashback-42-h910-harmonizer-product|title = 50th Flashback #4.2: H910 Harmonizer® — the Product|date = 23 April 2021}} released in 1975, was one of the first commercially available pitch-shifters and digital multi-effects units. On November 10, 1976, Eventide filed a trademark registration for "Harmonizer" and continues to maintain its rights to the Harmonizer trademark today.{{cite web |url=https://www.eventideaudio.com/news/corporate/eventide-inducted-tec-award-hall-fame-h910-harmonizer-pitch-processor |title=Eventide Inducted into TEC Award Hall of Fame for H910 Harmonizer Pitch Processor {{!}} Eventide |website=www.eventideaudio.com |url-status=dead |archive-url=https://web.archive.org/web/20200810061714/https://www.eventideaudio.com/news/corporate/eventide-inducted-tec-award-hall-fame-h910-harmonizer-pitch-processor |archive-date=2020-08-10}}

In digital recording, pitch shifting is accomplished through digital signal processing. Older digital processors could often shift pitch only in post-production, whereas many modern devices using computer processing technology can change pitch values virtually in real time.{{Cite web|url=http://www.soundonsound.com/sos/aug02/articles/tcvoiceone.asp|title=Voice Modelling Processor|publisher=Sound on Sound 2002|access-date=17 February 2011}}

Pitch correction is a form of pitch shifting and is found in software such as Auto-Tune and Melodyne to correct intonation inaccuracies in a recording or performance. Pitch shifting may raise or lower all sounds in a recording by the same amount, whereas in practice, pitch correction may make different changes from note to note.{{Cite web|url=http://emusician.com/tutorials/making-tracks-pitch-doctor/|title=Making Tracks: Pitch Doctor|publisher=Penton Media - date undisclosed|access-date=17 February 2011|url-status=dead|archive-url=https://web.archive.org/web/20100805084757/http://emusician.com/tutorials/making-tracks-pitch-doctor/|archive-date=5 August 2010}}

Pitch shifting can be used in DJing for harmonic mixing, a technique of matching the musical key of tracks in a DJ mix to avoid dissonance and create harmonious mixes or mashups. If a DJ wishes to mix two tracks which are not in compatible keys, they can shift the pitch of one track so that its key is compatible with the other, allowing seamless transitions between tracks which might otherwise sound dissonant when played together.

Numerous cartoons have used pitch shifters to produce distinctive animal voices. Alvin and the Chipmunks recordings with David Seville (aka Ross Bagdasarian) were created by recording vocal tracks at slow speeds, then playing them back at normal speeds. Voice artist Mel Blanc used pitch shifting techniques to create the voices of Tweety and Daffy Duck.{{Cite web|url=http://toolooney.goldenagecartoons.com/daffy.htm|title=What makes Daffy Duck?|publisher=Top looney golden age cartoons - date undisclosed|access-date=17 February 2011|url-status=dead|archive-url=https://web.archive.org/web/20110608212719/http://toolooney.goldenagecartoons.com/daffy.htm|archive-date=8 June 2011}}

In the 1970s, reruns of shows like I Love Lucy were sped up in order to run more advertisements during commercial breaks. The Eventide H910 Harmonizer was used to downward pitch-shift the characters' voices back to normal after the episode was sped up.{{Cite web|url=https://www.eventideaudio.com/blog/aagnello/50th-flashback-43-h910-harmonizer-minds-blown|title = 50th Flashback #4.3: H910 Harmonizer® —"Minds Blown"|date = 28 April 2021}}

South Park creators Trey Parker and Matt Stone have used pitch shifting for most of their characters throughout the show's run.{{Cite web|last=Ago|first=Keithperreaultin #entertainment • 3 Years|date=2018-01-07|title=South Park: An Analysis on the Pitch Effect in Music|url=https://steemit.com/entertainment/@keithperreault/south-park-an-analysis-on-the-pitch-effect-in-music|access-date=2021-05-12|website=Steemit|language=en}}

One notable early practitioner of pitch shifting in music is Chuck Berry, who used the technique to make his voice sound younger. Many of the Beatles' records from 1966 and 1967 were made by recording instrumental tracks a half-step higher and the vocals correspondingly low. Examples include "Rain", "I'm Only Sleeping", and "When I'm Sixty-Four".

Electronic musician Burial is known for including pitch-shifted samples of vocal melodies in his songs.{{cite journal |last=Jenkins |first=Pete |title=Dubstep Basics: An Introduction To Dubstep Production |journal=Sound on Sound |date=July 2010 |url=http://www.soundonsound.com/sos/jul10/articles/dubstep.htm }}

Goregrind and occasionally death metal use vocals that are often pitch-shifted to sound unnaturally low and guttural.

The famous bass intro to the song "Seven Nation Army" by The White Stripes, is the result of guitarist Jack White playing an electric guitar through a pitch shifting effects pedal set to an octave below. The band was a duo, who lacked a bassist and had never previously used one in any of their music, choosing instead to mimic the sound of a bass guitar.{{cite journal |last=Martin |first=Daniel |title=20 Things You Might Not Know About 'Seven Nation Army'|journal=NME |date=13 May 2013 |url=http://www.nme.com/blogs/nme-blogs/20-things-you-might-not-know-about-seven-nation-army-769531|access-date = 19 January 2017 }}

From 1986 to 1988, American musician Prince used pitch shifting to create his “Camille” vocals.

The coda in the song “The Bewlay Brothers” by David Bowie features Bowie’s voice distorted by varispeeding; this effect also appears throughout Bowie’s 1967 song “The Laughing Gnome”.

• Audio time stretching and pitch scaling
• DigiTech Whammy
• Pitch control
• Puberphonia

{{reflist}}

• [http://www.guitarpitchshifter.com/pitchshifting.html Pitch shifting explained]
• [http://my.fit.edu/~vkepuska/ece3551/The%20DSP%20Dimension/Tutorials/TimeStretchingOverview.pdf Time Stretching And Pitch Shifting of Audio Signals] by Stephan M. Bernsee
• [https://github.com/janesconference/KievII/blob/master/dsp/pitchshift.js pitchshift.js from KievII] Pitch shifter algorithm in Javascript, from [https://github.com/janesconference/KievII KievII library]

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Category:Audio engineering

Category:Digital signal processing

Category:Effects units

Category:Sound recording