Classical Musicians in Times Square, NYC

On the way down from the Bronx to Times Square Station, me and my group saw young classical musicians playing under the banner of "Music Under New York" (MUNY). They played a great Mozart's "A Little Night Music" and a Pachabel's Canon. It was a boy and girl on the violin, a girl on the viola, and a girl n the cello. Anyone know where these people appear?

If only we had more of such great musicians playing on the streets. I know the crowd appreciated them, because lots of people were throwing dollars into the girl's cello case.