Whether you are at the Buddha Bar in Paris or the shoe department at Nordstrom, sound puts you in the mood. Sound also sends a signal: “Hail to the Chief” announces the president’s arrival, and Looney Tunes cartoons always ends with a “Tha-a-a-t’s all folks.” A foreign accent adds cachet to almost any brand. Being put on hold might mean a little Bach cantata, a humorous sound sales pitch, or a radio station (don’ t you hate that?).