Conversation so far:
What kind of music did the Beatles create on the album Rubber Soul?
Author Andrew Grant Jackson describes the album Rubber Soul by The Beatles as a synthesis of folk, rock, soul, baroque, proto-psychedelia, and the sitar.
What was significant about the Beatles' music on the album Rubber Soul?
In their new songs, the Beatles drew inspiration from soul music, particularly the singles they heard on US radio the summer of 1965.

Question: What else is significant about their music?
Self-contained rewrite: What else is significant about the Beatles' music on the album Rubber Soul besides drawing inspiration from soul music?