Yamaha YHT-397 5.1-Channel Home Theater System (Discontinued by Manufacturer) 5-channel powerful surround sound (100W per Channel) HD Audio format decoding: Dolby TrueHD and DTS-HD Master Audio; Dolby Digital Plus and DTS-HD High Resolution Audio 4K pass-through for next generation super high resolution images Front panel USB Digital Connection for iPod and iPhone YPAO sound optimization for automatic speaker setup