Denon AVR-5805 Digital Surround Receiver
For instance, you can wire a 6.1-channel home theater and still have enough extra channels for not just one but two remote-room stereo setups (the Denon provides four independent zones of source selection and volume control). Or set up two fully independent 5.1-channel surround systems, one in the main room and one upstairs, running them simultaneously with different surround modes. Or install a full-bore, 7.1-channel theater, a stereo "extension" room, and a mono zone with ganged ceiling speakers in the basement gym. And if that's not enough for you, the AVR-5805's twenty-two preamp-level audio outputs can be pressed into service any way you like. In short, what Denon has created is as much a multiroom A/V controller as it is an A/V receiver.
I must also mention the auto-EQ (equalization) system, which is even more sophisticated than the one on Denon's AVR-2805, which I reviewed last December (click here to read the review). Using proprietary MultiEQ/xt technology licensed from Audyssey Labs, the AVR-5805 performs similar auto-setup and calibration chores (speaker size, distance, and level) but also establishes the best subwoofer crossover frequency for each individual main channel. It can then equalize its output signals to achieve "flat response" among all your speakers - or if you prefer, to match the response of the surround and center speakers with the front left/right pair.
What's special is that the EQ process incorporates corrections to reduce the impact of room acoustics on the sound for all listeners. That's no small feat. Typically, trying to use EQ to correct room-based frequency-response errors is like trying to squeeze out a big bubble when you're hanging wallpaper: you can usually move the problem around to different spots, but you can't get rid of it. The MultiEQ/xt room corrections actually work, though - and not for just one listener with his head in a vise.
One more feature in the feature-laden Denon flagship cannot go without comment: it provides three digital connection options for multichannel DVD-Audio or SACD music playback. A Denon Link connector (a dedicated, Ethernet-style RJ-45 jack) accepts a digital DVD-Audio or Dolby Digital/DTS signal from compatible Denon players like the DVD-3910 (click here to read the review). Two IEEE 1394 (FireWire) connectors do the same but also accept digital signals from multichannel SACDs. There are three HDMI digital A/V inputs, which for now pass only two-channel DVD-A/SACD or multichannel Dolby Digital/DTS audio signals. Den-on hopes to provide a firmware update once multichannel standards are ironed out.