text: To complete the many songs needed for their double-LP, The Beatles recorded regularly during twenty weeks from 30th May to 16th October 1968. The final studio date was a 24-hour marathon session to create the running order for the four sides of the album and the edits and cross-fades between the songs. The sessions mark an important turning point in their recording career because it was during this period that The Beatles first recorded on an eight-track tape machine.
  Since 1964, the group had used four-track for all their album albums by but 1966, they found their musical arrangements usually required more tracks than were available. The solution was the create extra ones by copying the first four tracks to a second blank tape and simultaneously mixing some of them together to leave free as many racks as were needed for addition overdubs. Bouncing Down was a time consuming process because the tracks that were being mixed together would form part of the final sound balance of the completed song so it was important to be satisfied with the mix before overdubbing commenced. With eight tracks now available, the problem was eliminated - until even more were needed.
  Work began on the album using four tracks and, while some songs could be confined to these, most had to be bounced down to a second, third, or even - as with Revolution 1 and Ob-LA-Di, Ob-La-Da - a fourth tape. The Beatles first experience of using an eight track recording at Abbey Road was during a session on 3rd September for While My Guitar Gently Weeps. As it had been started on four-track. the master was transferred to an eight-track machine to allow further overdubbing.
  However, While My Guitar Gently Weeps was re-recorded on eight-track from scratch two days later with a guest appearance by Eric Clapton. and completed on 6th September with several overdubs. Georges decision to ask a friend to play on his song was a significant one. Although The Beatles had previously used other musicians on their sessions, they had been from other areas of music such as classical, jazz or Indian music. For the first time, here was a star musician performing on an instrument already featured in the group.
  The albums long sessions would often begin in the afternoon and continue until daybreak the next morning. There were also occastions when two songs were recorded at the same time in separate studios. In July, engineer Geoff Emerick left the sessions and did not work with the group again until nearly a year later the Abbey Road. Ken Scott, who has first sat at the mixing desk for some of the Magical Mystery Tour songs, recored and mixed two thirds of The White Album. For one week, George Matin relinquished his seat in the room so that he could take a holiday and, consequently, his 21-year old production assistant Chris Thomas supervised sessions.