Conversation so far:
Is La Monte Young still actively making music?
La Monte Young  musical career has been active 1958 through present.
Has La Monte Young released any albums since 1970?
In 1974, the two released Dream House 78' 17.

Question: Who is the other person in the two?
Self-contained rewrite: Who is the other person besides La Monte Young in the two releasing Dream House 78' 17?