Conversation so far:
did Billy Corgan release any songs as a solo artist?
in 2004, he began a solo music career.
What is Zwan?
the band.
who else was in Zwan?
Corgan's old friend Matt Sweeney.
is anyone else in Zwan?
guitarist David Pajo and bassist Paz Lenchantin.

Question: what type of music did Zwan play?
Self-contained rewrite: what type of music did Zwan play?