The Pioneer VSX-523 AV Receiver With 140 Watts (1 kHz 1 % THD @ 6 Ohms 1ch Driven) or 80 Watts (20Hz-20kHz .08% THD @ 8 Ohms) clear audio reproduction and advanced new technologies such as 4K Ultra-High Definition Pass Through and an energy-saving ECO Mode, the new VSX-523 is the perfect entry-level receiver to introduce Pioneer's heritage of quality sound reproduction and innovative technology in your home entertainment system. Pioneer VSX-523 AV Receiver Apple Connectivity Continuing to lead the way in Apple connectivity, the VSX-523s front USB input now supports music playback and control for the new iPhone5 and iPad mini. The VSX-523 effortlessly brings all your entertainment sources together. Plug in a thumb drive into the front panel USB port and play back all your favorite music files, like MP3, WMA and AAC files. Pioneer VSX-523 AV Receiver Featuring HDMI with 3D and 4K Ultra HD pass-through. View larger Expanded HDMI Connectivity and Switching Functionality The VSX-523 features four HDMI inputs, providing connectivity for all your sources like Blu-ray Disc players, cable boxes, and gaming consoles. All four HDMI inputs support both 3D and new 4k Ultra HD content. Convenience features, such as, HDMI Standby Through is also supported allowing for your sources (cable box etc.) to pass through the receiver to the television even when it is in standby mode. When you're ready to upgrade your sources, so is the Pioneer VSX-523.