An external sound system completes a home theater, and turning one on yields unexpected pleasures. Recently, I stumbled upon a new TV series on HBO and a romantic drama on Blu-ray Disc both designed to indulge the ears.
The series, True Blood, features a waitress who can hear what people are thinking. As she works her way past tables, thoughts cascade toward her from every direction. And the audience hears the cacophony, too, brilliantly steered from multiple speakers at the sides of the TV and near the sofa.
The movie, August Rush, on Blu-ray and also available on DVD, features a humdinger of an opener: a child prodigy deciphers the musical nature of wind rustling the field in which he's standing. As the wind shifts, the sound washes over the audience from various directions. The powerful effect is all but lost on viewers relying on the TV's internal speakers alone. The same is true for the restaurant sounds in True Blood.

Sony STR-DG820 7.1-Channel Home Theater Receiver