Recording began on 23 February 1967. Using a four-track recorder, this first performance featured Harrison's guitar on track 1, Lennon's guitar on track 2, Ringo's drums on track 3, and McCartney's piano set on track 4. The band later added lead vocal, bass, and a three-part backing vocal section. By 21 March, the final mono mix was completed and a month later, the stereo mix was done.