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A Brief History of Pitch Correction in Music
Even with the mid-20th century’s recording studio wizards, if you were a vocalist who sang off pitch, solutions were time-consuming, difficult, and not always ideal. In the 1950s, capable vocalists could get by with a little spring reverb and maybe some slap back echo. Later, in the 1960s, singers could multitrack their vocals and apply other effects like tremolo (Tommy James on “Crimson & Clover”). John Lennon, famously insecure about his own voice, had engineer Geoff Emerick run his vocals through a gerry-rigged Leslie organ speaker to create a vibrato effect for “Tomorrow Never Knows.”
Beyond these effects, if a vocalist couldn’t sing on pitch throughout a recording, it was difficult to mask, and required more drastic measure. But like most anything in the 20th century, the technological solutions for off-pitch vocals were waiting to be discovered.
Variable tape speed
By the 1940s, studio engineers could produce primitive pitch correction by tweaking a reel-to-reel magnetic tape recorders varispeed. This process became more popular in recording studios during the 1950s and 1960s. By slowing down or speeding up a part of a recording and splicing with the tape containing the majority of the song, engineers could alter pitch. Another method of varispeed pitch correction was to slow a tape machine down, re-record a new part at a lower pitch, and then bring the recording back up to its original speed.
One of the most famous examples of varispeed pitch correction is the recording of The Beatles 1967 single “Strawberry Fields Forever.” The song as we know it is not one single take, but two takes (7 and 26) spliced together by producer George Martin and his innovative engineer Geoff Emerick. The Beatles had recorded these two takes at slightly different tempos and pitches. By speeding up the slower of the two tracks, Emerick was able to match the tempo and pitch.
Digital vocal tuning arrives
Eventide, a well-known manufacturer of effects units, originally made its mark with the Harmonizer H910, the world’s first digital effects unit. Introduced in 1975, the H910 was an early type of pitch correction device. But it was very far from something like the Auto-Tune plug-in. The H910 allowed users to make modest pitch corrections, though digital artifacts emerged when the original pitch was too radically altered. Thus, by today’s standards, its pitch corrections capabilities were extremely limited.
Over the years, Eventide made improvements on the Harmonizer’s pitch correction in different models, but it remained a far cry from Auto-Tune. Engineers still had to do overdubs on specific parts of vocal tracks to bring them back into pitch.
In the early 1980s, the French musical instrument company Publison released the Infernal Machine 90, an early hybrid digital signal processor and sampler. In addition to its pitch shifting/harmonizing capabilities, the Infernal Machine could apply delay and reverb to sounds put through it, as well as reverse and loop samples. It was a highly capable and cutting edge machine for its time, allowing users to change pitch without affecting the time signature. But compared to the Harmonizer, the Infernal Machine is incredibly rare and expensive.
Sampler-based pitch correction
The rise of samplers during the 1980s offered yet another pitch correction solution. The Fairlight CMI, a highly advanced digital sampler, synthesizer, and workstation (basically a proto-DAW), first released in 1979 but popularized in the ‘80s, was one such sampler. Incredibly expensive, it allowed musicians like Peter Gabriel, Kate Bush, Trevor Horn (Art of Noise), and others to sample any sound into it and have real-time pitch control over it.
The cool thing about the Fairlight CMI is that it allowed musicians, engineers, and producers to look at a graphical waveform of a song’s sounds. Users could identify—much like in a contemporary DAW—where a vocal track went off-pitch, then record a replacement sample and paste it in.
One of Fairlight’s direct competitors, New England Digital Corporation, also featured sampling capabilities on its Synclavier II and PMT machines. The Synclavier sampler workstations boasted direct-to-disk recording, and it was non-destructive; meaning, unlike with tape, you could always start again with a clean slate, and the recorded sound didn’t degrade. On top of this, much like the Fairlight CMI, the Synclavier displayed sounds as waveforms, allowing users to pinpoint a vocal that was off-pitch, dump a new recording into it, modulate the pitch wheel, and thus correct it.
Other samplers, like the Ensoniq Mirage and Akai S1000, gave users high sampling rates, allowing them to sample and play with vocal pitch for electronic music tracks. Most often, these machines were used to radically re-pitch vocals and other sounds. So while they weren’t typically used to subtly pitch-correct vocals for a pop song, they had the capability.
Going global with Auto-Tune
All of this brings us to the present day, at least to technology developed that is still used for contemporary recordings. In the early 1990s, Pro Tools began taking over professional recording studios. Fairlight CMI and Synclavier may have been the first DAWs, but Pro Tools was the first modern DAW software.
Pro Tools first appeared in 1984 as Sound Designer, around the time that the Fairlight CMI and Synclavier were doing most of their business in recording studios. Originally, it was designed by its creators, Evan Brooks and Peter Gotcher, to edit sounds on samplers like the E-mu Emulator sampling keyboard. Eventually, the two launched the company Digidesign, and began building what we now know as Pro Tools, the true predecessor to Logic, Ableton Live, Acid Pro, and other DAWs. It was on Pro Tools that pitch correction would be truly revolutionized.
In 1997, Antares Audio Technologies released Auto-Tune, the pitch correction we all either love or loathe. Invented by Andy Hildebrand, a former Exxon employee who made a fortune mapping seismic data for the oil giant, the Pro Tools plug-in allowed producers to tune vocals with an ease and speed that was unprecedented. A year later, as many people may already know, it appeared on Cher’s massive dance single “Believe.” Though the song’s producers used it for aesthetic effect, Auto-Tune was generally used to make unsuspecting pitch corrections to pop songs. What was designed to be aurally inconspicuous had now become an easily identifiable effect.
While T-Pain gets a lot of credit for popularizing Auto-Tune for Hip-Hop and R&B music production in 2005, he himself credits The Darkchild remix of Jennifer Lopez’s song “If You Had My Love” with influencing his approach to the plug-in. Instead of being a mere aesthetic flourish, T-Pain made Auto-Tune the primary vocal texture, giving his songs a warbly digital artifact that inspired a legion of imitators, from Nikki Minaj to Kanye West, who used it excessively on his 2008 album 808 & Heartbreak.
Over twenty years after its introduction, Auto-Tune is a globally ubiquitous. Bollywood singers use it for aesthetic effect, as do Reggaeton artists in the Caribbean countries. But again, it’s still used on recordings to provide a simple corrective for slightly off-pitch vocals. And it would be astonishing if K-Pop artists don’t use pitch correction, given the demand for perfect audiovisual presentation.
Other pitch correction solutions
Of course, Auto-Tune isn’t the only product used for pitch correction of vocals. Celemony’s Melodyne plug-in, found in studios all over the world, allows producers to process pitch in various ways. Melodyne 4 essential comes bundled with Nectar 3. Check it out!
If history is any indication, other solutions might well arise in the future. And as this brief history demonstrates, since recorded music came of age, tuning vocals has always been of interest to musicians, producers, and labels. Whether these folks use such this pieces of software in subtle or loud ways, the desire for perfect vocal takes will likely never wane.