Pitch shift
Encyclopedia
Pitch shifting is a sound recording technique in which the original pitch
of a sound is raised or lowered. Effects unit
s that raise or lower pitch by a pre-designated musical interval are called "pitch shifters" or "pitch benders".
, often by covering it with layers of suitable material, or on earlier wire recorders which have basically the same principle. Altering the capstan diameter affects the speed at which the tape registers sound, which in turn alters pitch. As technologies improved later designs of motor speeds could be controlled by electronic servo
system circuits. This arrangement using “vari-speed” capstan motors allowed the speed change to be achieved more simply. As for vinyl records, the same thing can be done;
placing a finger on the turnable to give friction will retard it, while giving it a 'spin' can advance it. However altering pitch and time independently is much more difficult.
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 octave
s, 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 "shifted" pitch with the original pitch to create a two or more note harmony.
In digital recording, pitch shifting is accomplished through digital signal processing
. Older digital processors could often only shift pitch in post-production
, whereas many modern devices using computer processing technology can change pitch values in real time.
Pitch shifting should not be confused with pitch correction
, a process that uses digital signal processing (DSP) software such as "Auto-Tune
" to correct intonation inaccuracies in a recording or performance. Pitch shifting raises or lowers each pitch in a recording by the same diatonic interval
, whereas pitch correction makes different changes from note to note.
recordings with David Seville (aka Ross Bagdasarian) were created by recording vocal tracks at a slow speed, then playing them back at normal speeds. Voice artist Mel Blanc
used pitch shifting techniques to create the voices of Tweety
and Daffy Duck
.
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
".
The metal genre grindcore
commonly uses pitch shifters to lower the pitch of the vocals, especially the goregrind sub-genre.
Pitch (music)
Pitch is an auditory perceptual property that allows the ordering of sounds on a frequency-related scale.Pitches are compared as "higher" and "lower" in the sense associated with musical melodies,...
of a sound is raised or lowered. Effects unit
Effects unit
Effects units are electronic devices that alter how a musical instrument or other audio source sounds. Some effects subtly "color" a sound, while others transform it dramatically. Effects are used during live performances or in the studio, typically with electric guitar, keyboard and bass...
s that raise or lower pitch by a pre-designated musical interval are called "pitch shifters" or "pitch benders".
Pitch/time shifting
The simplest methods are used to increase pitch and reduce note durations, or vice versa, reduce pitch and increase note duration. This can be done by replaying a sound waveform at a different speed than it was recorded. It can be accomplished by changing the diameter of the capstan drive shaft, or using a different more; on a reel-to-reel tape recorderReel-to-reel audio tape recording
Reel-to-reel, open reel tape recording is the form of magnetic tape audio recording in which the recording medium is held on a reel, rather than being securely contained within a cassette....
, often by covering it with layers of suitable material, or on earlier wire recorders which have basically the same principle. Altering the capstan diameter affects the speed at which the tape registers sound, which in turn alters pitch. As technologies improved later designs of motor speeds could be controlled by electronic servo
Servo
Servo may refer to:* Servomechanism, or servo, a device used to provide control of a desired operation through the use of feedback** Servo , a small, cheap, mass-produced actuator used for radio control and small robotics** Servo bandwidth...
system circuits. This arrangement using “vari-speed” capstan motors allowed the speed change to be achieved more simply. As for vinyl records, the same thing can be done;
placing a finger on the turnable to give friction will retard it, while giving it a 'spin' can advance it. However altering pitch and time independently is much more difficult.
Pitch shifter and harmonizer
A pitch shifter is a sound effects unitEffects unit
Effects units are electronic devices that alter how a musical instrument or other audio source sounds. Some effects subtly "color" a sound, while others transform it dramatically. Effects are used during live performances or in the studio, typically with electric guitar, keyboard and bass...
that raises or lowers the pitch
Pitch (music)
Pitch is an auditory perceptual property that allows the ordering of sounds on a frequency-related scale.Pitches are compared as "higher" and "lower" in the sense associated with musical melodies,...
of an audio signal
Audio signal
An audio signal is an analog representation of sound, typically as an electrical voltage. Audio signals may be synthesized directly, or may originate at a transducer such as a microphone, musical instrument pickup, phonograph cartridge, or tape head. Loudspeakers or headphones convert an electrical...
by a preset interval
Interval (music)
In music theory, an interval is a combination of two notes, or the ratio between their frequencies. Two-note combinations are also called dyads...
. 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 octave
Octave
In music, an octave is the interval between one musical pitch and another with half or double its frequency. The octave relationship is a natural phenomenon that has been referred to as the "basic miracle of music", the use of which is "common in most musical systems"...
s, 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 "shifted" pitch with the original pitch to create a two or more note harmony.
In digital recording, pitch shifting is accomplished through digital signal processing
Signal processing
Signal processing is an area of systems engineering, electrical engineering and applied mathematics that deals with operations on or analysis of signals, in either discrete or continuous time...
. Older digital processors could often only shift pitch in post-production
Post-production
Post-production is part of filmmaking and the video production process. It occurs in the making of motion pictures, television programs, radio programs, advertising, audio recordings, photography, and digital art...
, whereas many modern devices using computer processing technology can change pitch values in real time.
Pitch shifting should not be confused with pitch correction
Pitch correction
Pitch correction is the process of correcting the intonation of an audio signal without affecting other aspects of its sound. Pitch correction first detects the pitch of an audio signal , then calculates the desired change and modifies the audio signal accordingly...
, a process that uses digital signal processing (DSP) software such as "Auto-Tune
Auto-Tune
Auto-Tune is a proprietary audio processor created by Antares Audio Technologies. Auto-Tune uses a phase vocoder to correct pitch in vocal and instrumental performances. It is used to disguise off-key inaccuracies and mistakes, and has allowed singers to perform apparently perfectly tuned vocal...
" to correct intonation inaccuracies in a recording or performance. Pitch shifting raises or lowers each pitch in a recording by the same diatonic interval
Interval (music)
In music theory, an interval is a combination of two notes, or the ratio between their frequencies. Two-note combinations are also called dyads...
, whereas pitch correction makes different changes from note to note.
Notable uses
Numerous cartoons have used pitch shifters to produce distinctive animal voices. The ChipmunksThe Chipmunks
Alvin and the Chipmunks is an American animated music group created by Ross Bagdasarian, Sr. in 1958. The group consists of three singing animated anthropomorphic chipmunks: Alvin, the mischievous troublemaker, who quickly became the star of the group; Simon, the tall, bespectacled intellectual;...
recordings with David Seville (aka Ross Bagdasarian) were created by recording vocal tracks at a slow speed, then playing them back at normal speeds. Voice artist Mel Blanc
Mel Blanc
Melvin Jerome "Mel" Blanc was an American voice actor and comedian. Although he began his nearly six-decade-long career performing in radio commercials, Blanc is best remembered for his work with Warner Bros...
used pitch shifting techniques to create the voices of Tweety
Tweety
Tweety Bird is a fictional Yellow Canary in the Warner Bros. Looney Tunes and Merrie Melodies series of animated cartoons. The name "Tweety" is a play on words, as it originally meant "sweetie", along with "tweet" being a typical English onomatopoeia for the sounds of birds...
and Daffy Duck
Daffy Duck
Daffy Duck is an animated cartoon character in the Warner Bros. Looney Tunes and Merrie Melodies series of cartoons, often running the gamut between being the best friend and sometimes arch-rival of Bugs Bunny...
.
One notable early practitioner of pitch shifting in music is Chuck Berry
Chuck Berry
Charles Edward Anderson "Chuck" Berry is an American guitarist, singer, and songwriter, and one of the pioneers of rock and roll music. With songs such as "Maybellene" , "Roll Over Beethoven" , "Rock and Roll Music" and "Johnny B...
, 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
Rain (The Beatles song)
"Rain" is a song by the English rock band The Beatles, credited to Lennon–McCartney. It was first released in June 1966 as the B-side of the "Paperback Writer" single...
", "I'm Only Sleeping
I'm Only Sleeping
"I'm Only Sleeping" is a song by The Beatles from their 1966 studio album Revolver. It was released two months earlier in the United States on the album Yesterday And Today and did not feature on the original US version of Revolver...
", and "When I'm Sixty-Four
When I'm Sixty-Four
"When I'm Sixty-Four" is a song by The Beatles, written by Paul McCartney and released in 1967 on their album Sgt. Pepper's Lonely Hearts Club Band.-Composition:...
".
The metal genre grindcore
Grindcore
Grindcore is an extreme genre of music that started in the early- to mid-1980s. It draws inspiration from some of the most abrasive music genres – including death metal, industrial music, noise and the more extreme varieties of hardcore punk....
commonly uses pitch shifters to lower the pitch of the vocals, especially the goregrind sub-genre.
See also
- Effects unitEffects unitEffects units are electronic devices that alter how a musical instrument or other audio source sounds. Some effects subtly "color" a sound, while others transform it dramatically. Effects are used during live performances or in the studio, typically with electric guitar, keyboard and bass...
- Audio timescale-pitch modificationAudio timescale-pitch modificationTime stretching is the process of changing the speed or duration of an audio signal without affecting its pitch.Pitch scaling or pitch shifting is the opposite: the process of changing the pitch without affecting the speed...
- Pitch controlPitch controlA variable speed pitch control is a control on an audio device such as a turntable, tape recorder, or CD player that allows the operator to deviate from a standard speed . The latter term "vari-speed" is more commonly used for tape decks, particularly in the UK...
- Timestretching
- Short-time Fourier transformShort-time Fourier transformThe short-time Fourier transform , or alternatively short-term Fourier transform, is a Fourier-related transform used to determine the sinusoidal frequency and phase content of local sections of a signal as it changes over time....
- DigiTech WhammyDigitech Whammy-Overview:The WH-1 Whammy pedal, the original whammy, first engineered and manufactured in 1989 by IVL Technologies and discontinued in 1993, remains the most sought-after.-Controls:...
External links
- Pitch shifting explained
- 4 Band Pitchshifter Open Source VST Pitch shifter based on Stephan M. Bernsee article.
- Time Stretching And Pitch Shifting of Audio Signals by Stephan M. Bernsee
- pitchsift.js from KievII Pitch shifter algorithm in Javascript, from KievII library