Isolated vocals. It is interesting to read the commentary here. As a clearly older cultural observer, it is interesting to me to trace attitudes toward the Beach Boys through the years. I remember when for a short time they were dismissed by politically aware musicians and others. Then it was discovered (mainly by “hippies”) that the Beach Boys had unconsciously achieved the bliss the counterculture was searching for! I kid you not. It was a common belief.
Anyway, surf music has, of course, been very influential in subsequent years, and almost everyone will assert the cultural and musical importance of “Pet Sounds”. (In a well-known example, Sgt. Pepper’s Lonely Hearts Club Band was powerfully influenced by Pet Sounds.)