Brown left The Freshmen in the mid 1970s to pursue other musical challenges, albeit with limited success.

A particularly difficult musical challenge has been taken up successfully by Tyagaraja in three of these compositions.

Did he take it as a musical challenge to follow the soloist's lead and embrace his interpretive concept?

Composers of more recent times have composed études that explore technical and musical challenges particular to contemporary music.

"For me it was a musical challenge, and I didn't care if it was going to succeed," he said.

The musical challenge of this dark and remarkable work is to make its many varied episodes into one seamless, arching whole.

Though not all of the 19 actors are able to meet the musical challenge, they share an earnestness and an enthusiasm.

Jazz players and singers have enjoyed the musical challenges of this song for decades.

Now he is "almost fearless" about facing new musical challenges, he said.

Beyond covering Mr. Joel's songs, the young musicians were also looking for a musical challenge.