This is what I wrote about it over at Audioholics:
I recently traded in my Denon 3805 to the new 4806. Hi-fi Buys has an awesome trade up system.
Anyway, the 4806 is an extremely large receiver, well not as big as the 5805, but a lot bigger and heavier than my 3805. But this is to fit all the extras into it. I never realized how large the transformer was on the 4806 until I got it home; I had only seen them in pictures on the web. The 3805's transformer pales in comparison to the 4806. I'm guessing that it's also used in the 5805. The 4806 also run very warm after being in use for a little while. You can feel a lot of heat rising out of the amp sections on either side of the receiver. Lets just say, if you have a small room, it will heat it up rather quickly.
When I got it home, making all the connections was easy. I'd be surprised if anyone could use all of them on the back. Next I went through the various on screen displays to setup my system. Set all the speakers to small, left the sub crossover at THX fixed which I am assuming is 80Hz, assigned the various digital inputs to the appropriate video input, etc. Let me tell you there are A LOT of options in this thing! I really like the option where you can rename the inputs. For Example, I renamed VCR-1 to XBOX, so it displays XBOX on the front panel when selected.
Instead of setting the receiver up manually with a SPL meter like I did with my 3805, I decided to try the Audyssey auto setup. I placed the mic on my camera tri-pod in the main listening position for the first test. Luckily, the Denon mic is included with the 4806. When you first run the Audyssey it sends out a series of test tones to determine what speakers you have hooked up. Next it will ask you to place the mic in the main listening position and repeats the test. You do this a total of 7 more times in 7 different locations based around the main listening point. After the 8 points are finished calculates the results and determines the channel levels, speaker size, EQ, crossover, and distance.
What I found when I ran this test is that it configured my left, right, and center speakers as large and my surrounds as small. I eventually went back and set them back to small The distances were pretty dead on, and so were the channel levels. I only needed to adjust a few channels within 0.5dB. I did find it odd that Audyssey had adjusted almost all of my channels to negative 3-5dB. Why would it adjust them all the channels to negative? Why not leave some at 0 and adjust them accordingly? The crossover was set to something weird like Center: 40Hz, Left and Right: 60Hz, and the LFE was set at 80Hz. What I did like though were the EQ's that Audyssey generated. The one that I think sounded the best was Flat. When I played movies through the 4806 with flat enabled, it made the speakers seem seamless. Audyssey isn't perfect but it does do a good job getting you going and makes it easier for you to tweak the system. One of these days I'm going to get a good setup DVD so that I can configure the EQ myself.
The 4806 can really push my Polk speakers now. I have the Rti10's floor standing, Csi5 center channel, and Fxi3 surround speakers. Before with the 3805, it seemed as if the Rti10's were missing some mid range, but with the 4806, the sound is much more full. I'm not sure if this is because of the amp itself or the settings that Audyssey gave me for the EQ. All I know is that they do sound better.
I tried some different movies to test out my new setup and some Halo 2. I watched a lot of the Superbit DVD movie Fifth Element because I think it makes full use of the receiver's capabilities. The sound effects and the music sound really great, I think there were a few things in the movie that I had never really heard before or other sounds where just more clear and detailed. My favorite part of the movie is the Opera house scene; the music was very detailed and not overly bright. It just sounded perfect like you were there. Shortly after you get into some good action scenes with gunfights and explosions, all which the 4806 handled without a problem. However, the test that really impressed me the most was Halo 2. This game makes VERY good use of Dolby Digital 5.1 with sound all around you throughout the entire game. The 5.1 can be very helpful when fighting as you can hear enemies sneaking up behind you or gunfire. At one point in the game I heard a voice behind me, and I almost turned around to see who was there because it sounded so real.
Overall, I really like the 4806. It's a beast, yet very flexible. It will take anything you through at it and output it with finesse. I might have to upgrade to the Polk Lsi series one day to match the amp. I think if someone is really into home theater this is a good receiver to consider.
If anyone has any tips, tricks, or suggestions about how to setup this amp or anything else, please let me know. Maybe we will have to start a AVR-4806 owners thread soon!
Oh, yeah, its still the same remote we all love.
NOTE: I ran the Audyssey setup again but this time I held the mic in my hand and pointed it to each speaker during the 8 tests. This produced a much better setup for my room, speakers set to small, distance, etc. The Audyssey EQ sounded REALLY nice too this time. I would recommend trying this method if you are not satisfied with the Aydssey results the first time.