Ringtone vs. Music

When I took a freshman music course in Brooklyn College, the professor put on a record of a Beethoven concerto. He stood by the phonograph. clearly entranced by the music. Abruptly, he shut off the record, glared at two students who were talking and said,
"Beethoven is not for talking over. Class dismissed."
Yesterday, New York Philharmonic Conductor Alan Gilbert halted a performance of Mahler's Ninth Symphony because of a ringing iPhone.
Bravo!