Automatic pitch correction
Automatic pitch correction , also known as auto-tune , is a method of changing pitch in music production . The pitch (intonation) of an audio signal , mostly vocals , is corrected or changed without influencing the overtone structure and tempo .
history
Analog pitch correction
The correction of pitches only became possible through the recording of music and still varies today due to the quality of the recording and the technical possibilities. One of the first methods of recording music and thus correcting and manipulating it was the record. In analog pitch correction, a change in pitch is associated with a change in tempo and vice versa: the increase makes the recording faster, the decrease slower.
Digital pitch correction
The origins of digital pitch correction can be traced back to the first music computers that were used for scientific data processing in the 1950s. However, they were large and expensive and were replaced by smaller and cheaper models in the late 1960s. These devices were not yet able to process audio, but they could control analog devices. The actual development of today's digital pitch correction began in the 1970s.
functionality
Changing the pitch of a sound without changing the playback speed at the same time is known as pitch shifting . The separation of the dependence of the pitch and speed of an acoustic signal is also possible in an analogue manner, using rotating tape heads, but it is complex and the sound quality of the result is poor. Pitch shifting only became more widespread with the introduction of digital applications. The following techniques are used in most current pitch manipulation applications, and they are sometimes combined.
Granular synthesis
The granular synthesis is to generate a method to artificial sounds. A continuous sound is “simulated”, which in reality consists of individual grains . These grains are sound fragments around 50 milliseconds long that the listener cannot perceive as individual sound events due to their short duration. Granular synthesis is used for the resynthesis of sampled material. The recorded sound is analyzed and broken down into grains. This means that the pitch can now be changed as required regardless of the playback speed (and vice versa). Granular synthesis can be applied in real time .
Phase vocoder
When phase vocoding also is a re-synthesis process. Here the filters are connected in series as in a filter bank ; each filter filters out a certain range of frequencies and determines its volume. Using this data, a sound can now be reassembled, with sound properties and temporal structures being retained. The phase vocoder method cannot be used in real time.
Products (examples)
software
- virtually latency-free real-time sound manipulation
- In addition to editing recorded material, it is also suitable for live use
- Audio material is analyzed before processing and then manipulated in real time
- flexible interventions are possible, which would cause strong latencies with normal real-time processing
WaveLab / Time Factory (Prosoniq)
- Manipulation is factored into the audio file
- destructive editing (no return to the original material possible)
Mobile devices
- I Am T-Pain (Smule)
hardware
- TC-Helicon VoiceLive 2 Vocal Effects Processor
- DigiTech Vocalist Live 4 Harmony-Effects Processor
Reasons for application
In order to increase efficiency , repeated singing in the studio can be avoided, and a supposedly constant quality of the music can be suggested at concerts under different conditions . It is also possible to compensate for the singing performance of indisposed or unprepared artists. "Perfect" vocal recordings are thus possible in a significantly shorter time. There is also the possibility of using it as an aesthetic design tool to alienate voices.
Application examples
"I would dare to say that (pitch correction) is in almost all music you hear on pop radio to some extent."
"I dare to say that it (the pitch correction) is used to some extent in almost all pop music from the radio."
The most common use of automatic pitch correction is to perfect vocal tracks in popular music. The intensity of the application ranges from correcting individual notes to alienating the entire vocal characteristics. The alienation of the voice was first used as a stylistic device by various artists in the late 1990s. The best-known example is the song Believe by Cher from 1998 ( Cher effect ). The effect was also well known through the US rapper T-Pain , who uses it as his trademark in almost every piece of his music.
criticism
By immediately correcting the sung and played notes, the listener cannot recognize the intensity and quality of the processing; artists who seem to be perfectly intonated are presented to them at all times. In the past there have been protests against the use of pitch correction software by musicians: Among other things, the rapper Jay-Z published the title DOA (Death of Auto-Tune) in 2009 . The use of tone corrections is usually kept a secret among singers. The uniform sound of tonally correct music creates the impression that music is losing authenticity through the use of correction software. In contrast, manipulation of instrumental recordings is generally viewed as less critical. As a counter-movement, more and more music free of software and other manipulation instruments is demanded. Currently (as of 2009) dealing with pitch correction software has become more open again.
literature
- Philip von Beesten: Elastic Audio. The digital manipulation of pitch and time structures. Master's thesis at Leuphana University Lüneburg - Applied Cultural Studies - Music 2009.
- Michael Dickreiter, Volker Dittel, Wolfgang Hoeg, Martin Wöhr: Manual of the recording studio technology. KG Saur, Munich 2008, ISBN 978-3-598-11765-7 .
- Curtis Roads: microsound. The MIT Press, Cambridge MA 2001, ISBN 978-0-262-18215-7 .
Web links
- Jimmy Kimmel Live - T Pain Obama Auto-Tune
- Simon Reynolds: How Auto-Tune Revolutionized the Sound of Popular Music . Detailed article at pitchfork.com (English)
Individual evidence
- ↑ Philip von Beesten: Elastic Audio. The digital manipulation of pitch and time structures. . 2009. Archived from the original on July 14, 2016 Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Retrieved January 24, 2015. p. 3f.
- ↑ Philip von Beesten: Elastic Audio. The digital manipulation of pitch and time structures. . 2009. Archived from the original on July 14, 2016 Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Retrieved January 24, 2015. p. 28.
- ↑ Philip von Beesten: Elastic Audio. The digital manipulation of pitch and time structures. . 2009. Archived from the original on July 14, 2016 Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Retrieved January 24, 2015. p. 32.
- ↑ Curtis Roads: microsound. Pp. 86-118.
- ↑ Michael Dickreiter , Volker Dittel, Wolfgang Hoeg, Martin Wöhr: Handbook of Tonstudiotechnik. P. 87.
- ↑ Philip von Beesten: Elastic Audio. The digital manipulation of pitch and time structures. . 2009. Archived from the original on July 14, 2016 Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Retrieved January 24, 2015. pp. 50f.
- ↑ Christopher John Treacy: Fixing Flats. Paula pitchy? Not with an Auto-Tune up! Online . Quoted from Philip von Beesten: Elastic Audio. The digital manipulation of pitch and time structures. P. 70f.
- ↑ Philip von Beesten: Elastic Audio. The digital manipulation of pitch and time structures. . 2009. Archived from the original on July 14, 2016. Retrieved January 24, 2015. pp. 74, 87-88.
