Integra Power. The drx-4 combines accurate, noise-free signal processing with high-current power for dynamic speaker control. The result is pure, rich and authentic sound. Integra dynamic Audio amplification delivers 110 watts per Channel (8 ohms, 20 hz–20 kHz, 0. 08% THD, 2 channels Driven) with 35 Amps of high instantaneous current capability. Thx-certified. The drx-4 is certified select2 plus by THX. Thx spends 40-60 hours testing over 2000 data points ensuring that the drx-4 is capable of meeting rigorous Audio and video performance standards for reference level, distortion free playback and includes THX loudness plus technology to bring out intricate details at lower listening levels. Smooth Analog Signal. Vector Linear Shaping Circuitry (VLSC) removes pulse noise generated in D/A conversion and allows the sound wave to be reproduced with extremely high fidelity for a smooth analog signal. This is applied to the front left and right channels, which are also bi-ampable. Flexible zone 2. The drx-4 features powered zone 2 with a/B speaker selection to bring Audio to speakers connected to the receiver into a second room or third room. Zone 2 pre/line out Can be used with an Outboard amp, and a zone 2 DAC for HDMI inputs 1 through 3, coax and optical inputs (2-ch PCM), network (including Pandora and Spotify), and USB Audio sources. There are also maximum power and power on volume settings for the main zone, zone 2 as well as bass/treble and balance controls to further customize your listening experience and help get the best performance out of your speakers. HD Base Port for Multimedia Distribution. HD Base transmits audio and video signals clearly up to 328 feet utilizing cat5e/cat6 cable to any certified third party HD Base receiver or device that has its own power supply. This makes long distance runs to projectors or a second zone easy and reliable.