He prefers to not punch in or overdub vocals. McCartney added a final vocal overdub at the end of the session. On September 21, Brian completed the track after Tanner added a final Electro-Theremin overdub. The song only took two takes, along with a vocal overdub. Lead guitar and piano overdub is Stephen. Cobain's final contribution to the recording was a guitar overdub. The intention at one point was to have the two overdub solos playing together. He learned how to overdub, using his vocals and those of Carl and their mother. Only instrument overdub is additional guitar by Don. The line was recorded as an overdub using a separate guitar. A flanged backwards guitar overdub is also included. The producer solved this by muffling the buzzing with the ocean overdub. The album does not feature an overdub of guitars. There were certain tracks where Sherwood nailed the overdub in one take. Piano overdub by Stills at Criteria.