Editing Automatic double tracking (section)

==Use in music==
{{Excessive examples|section|date=August 2023}}

The Beatles used ADT widely in conjunction with manual double-tracking on all their subsequent albums, with the exception of ''[[Let It Be (album)|Let It Be]]'', which was initially intended to be an "honest" album utilising no technical artifice (ADT can still be heard on the finished album, however, because [[Phil Spector]] treated a [[Hammond organ]] part with it on his mix of the title track). Some notable examples of ADT used by the Beatles in the years following ''Revolver'' include "[[Within You Without You]]" (on which ADT was purportedly used on almost every vocal and instrumental part on the track), "[[I Am the Walrus]]" (which uses ADT in conjunction with [[Equalization (audio)|equalisation]] to help simulate a "fake stereo" effect on the second half of the stereo mix, which was sourced from the mono mix, by splitting the entire mix between the channels), and the unusually wide ADT used on the lead vocal tracks on "[[Being for the Benefit of Mr. Kite]]" and "[[Blue Jay Way]]". On "[[While My Guitar Gently Weeps]]", [[Eric Clapton]] used ADT to make his guitar sound 'less bluesy', according to [[Ian MacDonald]] in ''[[Revolution in the Head]]''.

===Other users of ADT===
Townsend's technique, and minor variations on it, quickly caught on with other artists and [[record producers]]. Former Beatles engineer [[Norman Smith (record producer)|Norman Smith]] used ADT extensively on [[Pink Floyd]]'s debut album ''[[The Piper at the Gates of Dawn]]'', recorded at Abbey Road in 1967. As well as using it for more conventional simulated double tracking, Smith made much use of the technique to split [[Syd Barrett]]'s vocals between the stereo channels. In some cases, Smith (or possibly Barrett himself) used such extraordinarily wide ADT in this way as to give the slightly disorientating impression of not so much double tracking but two quite separate voices on either channel wildly out of time with each other – the best example of this is perhaps on "[[Bike (song)|Bike]]". Similar effects were later used on some of Barrett's solo works, perhaps indicating his fondness for this unusual use of ADT. Pink Floyd themselves continued to use ADT on most, if not all, of their subsequent albums up until the 1980s, with one notable use being on "[[Alan's Psychedelic Breakfast]]", where a part of the drum track is treated with ADT.  
In the US, [[Simon and Garfunkel]] began to use ADT on stereo mixes of their songs to split vocal tracks between the channels, examples of which include "[[Mrs. Robinson]]" and "[[Cecilia (Simon & Garfunkel song)|Cecilia]]".

[[Gary Kellgren]], [[Jimi Hendrix]]'s engineer, used ADT extensively on all of Hendrix's albums. He frequently split vocal, guitar, and even drum parts between the stereo channels.

As the music industry's hunger for technological advances increased, new devices were created to make it easier and faster to achieve the same results.  Thus, the industry saw analogue delay devices created and brought to market that no longer needed tape machines to achieve the ADT effect.{{which|date=August 2023}}  They used electronic circuits instead. Much later on, these analogue delays were augmented by digital delay units. There has since been a thriving market among guitarists and other musicians for guitar pedals, or [[effects unit]]s, reproducing chorus and delay that owe their development to ADT. Nowadays, the ADT and similar effects are available as computer software plugins.

===Psychedelic music===
With the rise of psychedelic music, many artists used variations on Townsend's technique to create the "flanging" effect mentioned above, adding a slightly disorienting "swooshing" quality to instruments and voices (although in practice this effect is actually more similar to what today is called "[[phasing]]" rather than "flanging"). The Beatles themselves used this effect on "[[Lucy in the Sky with Diamonds]]" and more prominently on "Blue Jay Way". A notable example of this technique is "[[Itchycoo Park]]" by the [[Small Faces]], where the effect is prominent almost throughout the entire track, particularly on the vocals, drums and cymbals during the chorus. Hendrix also used this technique extensively. An example of an ADT variation being used to create an effect more similar to what is considered "flanging" today (rather than phasing) is on the Beatles' [[White Album]] tracks "[[Cry Baby Cry]]" (acoustic guitar) and "[[While My Guitar Gently Weeps]]" (lead guitar).

===Doubling echo===
{{Main|Delay (audio effect)}}

A similar technique to ADT is [[doubling echo]], which uses short delays to mimic the double-tracking effect. Many effects units were developed to produce similar sounds, such as [[chorus effect|chorus]], [[flanger]]s, and [[phaser (effect)|phasers]], all of which use an oscillating delay (or, in the phaser, a variable phase network).  Other notable uses of ADT doubling echo are apparent on select material by [[Elton John]].  Some examples of this can be heard on Nigel Olsson's drums, especially the tom toms, on the songs "[[Don't Let The Sun Go Down On Me]]" from the ''Caribou'' album, as well as "Better Off Dead" and 
"[[Someone Saved My Life Tonight]]" on ''Captain Fantastic and the Brown Dirt Cowboy''.