The only surviving full-band recording of "Surf's Up" from the 1960s is the basic backing track of the first movement. There are three known recordings of Wilson performing the full song by himself, two of which were filmed for the 1967 documentary "", where it was described as "too complex" to comprehend on a first listen. Several years after "Smile" was scrapped, the band added new vocals and synthesizer overdubs to Wilson's first piano performance as well as the original backing track. Another recording from 1967 was found decades later and released for the 2011 compilation "The Smile Sessions".