Guitarist and co-founder of the alternative rock band Smashing Pumpkins, he also helped form the supergroup Tinted Windows. He is also a member of A Perfect Circle.
He met Smashing Pumpkins frontman Billy Corgan at a record store. Corgan had already imagined a fictional band named Smashing Pumpkins.
After Smashing Pumpkins broke up in 2000, he wrote a well-received book of poetry and made a less popular introspective rock album.
He dedicated his song "For Martha" to his mother and named his label, Martha's Music, after her.