Editing Multitrack recording (section)

==Process==
[[File:Stax Records, Memphis, TN, US (10).jpg|right|thumb|Mixing desk with twenty inputs and eight outputs]]
Multitracking can be achieved with [[analogue recording]], tape-based equipment (from simple, late-1970s cassette-based four-track Portastudios, to eight-track cassette machines, to 2" reel-to-reel 24-track machines), digital equipment that relies on tape storage of recorded digital data (such as [[ADAT]] eight-track machines) and [[hard disk]]-based systems often employing a computer and audio recording software. Multi-track recording devices vary in their specifications, such as the number of simultaneous tracks available for recording at any one time; in the case of tape-based systems this is limited by, among other factors, the physical size of the tape employed.

With the introduction of [[SMPTE timecode]] in the early 1970s, engineers began to use computers to perfectly synchronize separate audio and video playback, or multiple [[audio tape machine]]s. In this system, one track of each machine carried the timecode signal, while the remaining tracks were available for sound recording. Some large studios were able to link multiple 24-track machines together. An extreme example of this occurred in 1982, when the rock group [[Toto (band)|Toto]] recorded parts of ''[[Toto IV]]'' on three synchronized 24-track machines.<ref name="Mix Online">[http://www.mixonline.com/news/profiles/classic-tracks-totos-africa/375305 Classic Tracks: Toto's "Africa"], Mixonline.com, Retrieved June 30, 2015.</ref> This setup theoretically provided for up to 69 audio tracks.

In the late 1970s and 1980s, digital multitrack tape machines emerged, including the 3M and Mitsubishi X-800 32-track machines, and Sony DASH PCM-3324 and later the PCM-3348 machines, which allowed greater flexibility with more available tracks for recording. <ref>{{cite web | url=https://www.mixonline.com/technology/1981-sony-pcm-3324-383671 | title=1981 Sony PCM-3324 | date=September 2006 }}</ref> As well, in order to mix using automation on the console, analogue recorders generally required adjacent tracks to the time code track to be kept blank to avoid the time code signal interfering with the audio signals, which limited available tracks to 22 or 23 track at most. Digital multitrack machines had time code inserted elsewhere on the tape, and thus did not require allocating it to an audio track, which meant all tracks were available for recording. What's more, in the case of the PCM-3348, which doubled the number of tracks from the PCM-3324, both machines could use the same ½” digital tape, and also a 24-track reel first recorded on a PCM-3324 was able to be used on a PCM-3348 and have another 24 tracks overdubbed.<ref>{{cite web | url=https://www.sony.net/Products/proaudio/en/story/story03.html | title=Sony Corporation - Sony's Professional Audio &#124; Story &#124; chapter 3 }}</ref>

For computer-based systems, the trend in the 2000s is towards unlimited numbers of record/playback tracks, although issues such as [[RAM]] memory and [[CPU]] available do limit this from machine to machine. Moreover, on computer-based systems, the number of simultaneously available recording tracks is limited by the number of [[sound card]] discrete analog or digital inputs.

When recording, [[audio engineer]]s can select which track (or tracks) on the device will be used for each instrument, voice, or other input and can even blend one track with two instruments to vary the music and sound options available. At any given point on the tape, any of the tracks on the recording device can be recording or playing back using [[Sel-Sync|sel-sync]] or Selective Synchronous recording. This allows an artist to be able to record onto track 2 and, simultaneously, listen to track 1, 3 and 7, allowing them to sing or to play an accompaniment to the performance already recorded on these tracks. They might then record an alternate version on track 4 while listening to the other tracks. All the tracks can then be played back in perfect synchrony, as if they had originally been played and recorded together. This can be repeated until all of the available tracks have been used, or in some cases, reused. During mixdown, a separate set of playback heads with higher fidelity are used.

Before all tracks are filled, any number of existing tracks can be ''bounced'' into one or two tracks, and the original tracks erased, making more room for more tracks to be reused for fresh recording. In 1963, [[the Beatles]] were using twin track for ''[[Please Please Me (album)|Please Please Me]]''. The Beatles' [[Record producer|producer]] [[George Martin]] used this technique extensively to achieve multiple-track results, while still being limited to using only multiple four-track machines, until an eight-track machine became available during the recording of the Beatles' [[The Beatles (album)|self-titled ninth album]]. [[The Beach Boys]]' ''[[Pet Sounds]]'' also made innovative use of multitracking with eight-track machines of the day (circa 1965).<ref>{{cite book |url=https://books.google.com/books?id=4Yoio9MewhcC |title=All You Need is Ears |first=George |last=Martin |publisher=[[St. Martin's Press]] |year=1994 |page=304|isbn=9780312114824 }}</ref> [[Motown]] also began recording with eight-track machines in 1965, before moving to 16-track machines in mid-1969.

[[File:TEAC 2340.jpg|thumb|The [[TEAC Corporation|TEAC]] 2340, a popular early (1973) home multitrack recorder, four tracks on ¼ inch tape]]
[[File:Korg D888.jpg|right|thumb|[[Korg]] D888 eight-track digital recorder]]
Multitrack recording also allows any recording artist to record multiple ''takes'' of any given section of their performance, allowing them to refine their performance to virtual perfection by making additional ''takes'' of songs or instrumental tracks. A recording engineer can record only the section being worked on, without erasing any other section of that track. This process of turning the recording mechanism on and off is called [[Punch in / out|punching in and punching out]].

When recording is completed, the many tracks are ''mixed down'' through a [[mixing console]] to a two-track [[stereo]] recorder in a format which can then be duplicated and distributed. (Movie and DVD soundtracks can be mixed down to four or more tracks, as needed, the most common being five tracks, with an additional [[low-frequency effects]] track, hence the ''5.1'' surround sound most commonly available on DVDs.)

Most of the records, CDs and cassettes commercially available in a music store are recordings that were originally recorded on multiple tracks, and then mixed down to stereo. In some rare cases, as when an older song is technically ''updated'', these stereo (or [[Monaural|mono]]) mixes can in turn be recorded (as if it were a ''submix'') onto two (or one) tracks of a multitrack recorder, allowing additional sound (tracks) to be layered on the remaining tracks.