Not that pop composers haven't tried to stretch out.
After spending seven years domesticating the former retreat of the pop composer and singer Carole King, they have decided to move again - to another run-down building.
Mr. Yazbek is a novice to the world of musicals, having worked mostly as a television script writer and a pop composer and performer.
The music of these experimental pop composers combines bubbling Afro-pop with classical innovation.
"I don't know much about pop composers who listen to contemporary music," he said.
The music and lyrics are by a pop composer new to the theater, Paul Gordon, but there are some substantial pedigrees involved as well.
Widely praised as one of the great pop composers of his time, he employed unusual harmonies.
Since the 1970s, the couple have focused strictly on the American pop repertoire, recording several albums themed around individual American pop composers.
He hopes to tackle this problem by bringing in pop composers to create works specifically for the Boston Pops.
George Gershwin, who began writing concert music in the 1920's, remains the most famous example of a pop composer crossing over into the classical realm.