Glenn Roth is not your typical commuter from Connecticut. Instead of a briefcase, he carries a gig bag. His workspace is the vaulted splendor of Grand Central Terminal or the tunnels and platforms of the New York City subway system. A literal “underground” sensation, Glenn is a licensed performer in the MTA’s “Music under New York” program, playing for the most distracted and demanding audience in the world: legions of workers rushing to jobs throughout the Big Apple. And his fingers work magic, creating a soundscape of compelling melodies that invite them to leave the city rush behind on an aural escape.