Comparing "Pet Sounds" to "Rubber Soul", author Michael Zager wrote that "Pet Sounds" has more in common with Spector's productions, and that the album recycles many of Spector's Wall of Sound production watermarks. Wilson said that he was especially fascinated by the process of combining sounds "to make another", and for "Pet Sounds", sought to emulate those aspects of Spector's productions. In a 1988 interview, Wilson said that his goal for the album was to "extend" Spector's music, as he believed that, "in one sense of the word", the Beach Boys were Spector's "messengers". On another occasion, Wilson credited "Rubber Soul" as his "main motivator" for "Pet Sounds". He explained that he wanted to create music "on the same level" as "Rubber Soul", but was not interested in copying the Beatles' music style. In 2009, he said that although ""Rubber Soul" didn't clarify my ideas for "Pet Sounds"", the Beatles' use of sitar inspired his choice of instrumentation for the album.