Although multitrack recorders were developed as early as the 1940s, at the time The Beatles started their professional recording career in 1962, two-track recording was still the industry norm.
By the early 1960s EMI's Abbey Road studio was equipped with four-track machines, but four-track recording was regarded as unnecessary for pop recordings and the Beatles themselves did not use the method until 1964. Despite this slow start, the 1960s became a time of rapid change in recording, with significant shifts in technology in recording studios and the Beatles at the forefront of these developments.
Driven by the desire of artists and the vision of engineers, the quest for new sounds often led to sophisticated technological developments and innovation. The relationship between the Beatles and their production team was no different - they constantly sought advancement in the way records were made. New techniques and sonic effects emerged through their recording sessions, such as Artificial Double Tracking (or ADT) for vocals which was invented by Abbey Road's studio manager Ken Townshend.
Often it was the Beatles' artistic demands that led technological innovation. For instance, the recording of Strawberry Fields took the form of two takes with distinctive arrangements. In the first take the band were accompanied by Paul McCartney's new Mellotron, a keyboard which generates sound by playing back pre-recorded tapes of instrumental samples. The second take included a brass and string arrangement written by producer George Martin. John Lennon suggested that the final record would work best with a splice between the first and second takes for each half of the song. Unfortunately, the two takes were in different keys, so the studio team had to improvise a way of joining the two by slowing the second take to the correct pitch and gradually decreasing the speed of the first before the edit point at one minute into the song.
The work of Martin and his team, alongside The Beatles, was highly influential on how records were made going forward. The band's immense popularity meant their innovative use of studio technology was heard all over the world, setting new benchmarks in record production. In fact, the recording studio became an important compositional tool within popular music. No longer did bands merely provide studio performances of already written and arranged compositions; the studio itself was being used to create the essential fabric of the music. As the world famous record producer Brian Eno said in 1979:
"You're working directly with sound, and there's no transmission loss between you and the sound - you handle it. The composer is in the identical position to the painter - he's working directly with a material, working directly onto a substance, and he always retains the options to chop and change." (Eno in Cox and Warner, 2004: 129)