In the concert hall, each motionless listener is part of the performance.  The concentration of the player charges the electric tension in the auditorium and returns to the playLIer magnified.  I like the fact that "LISTEN" is an anagram of "SILENT".  Silence is not something that is there before the music begins and after it stops.  It is the essence of the music itself, the vital ingredient that makes it possible for the music to exist at all.  It's wonderful when the audience is part of this productive silence.