I received my Yamaha RX-V665 yesterday and got it set up so I thought I'd post some initial impressions as I compare it to the UMC-1
and also my Onkyo TXSR-876 when used as a preamp-processor.
To wit; my system includes:
HTPC>ATI 4600 series>Xonar HD audio
Panasonic DMP-BD35 Blu-ray player
Dish Network VIP 211k HD receiver
JBL Professional actively bi-amped speakers, LSR6325P-1
Velodyne F1800RII 18" Subwoofer :-)
The Yamaha arrived from Amazon double boxed and the Yamaha box was one of the thickest I've ever seen, good stuff.
Initial setup was quick and easy, on-screen setup menu was intuitive and I didn't need to reference the manual at all.
I just did the manual speaker setup for now and haven't run the YPAO room correction yet.
The receiver was pre-set to pass-thru the HDMI video signal unaltered.
This appears to work perfectly, in fact my HTPC (ATI 4600 series)
doesn't "see" the receiver at all, but passes straight through to my
Epson 1080UB projector (shows EPSON PJ in display listing), nice!
For HTPC video adjustments I find that it works better to adjust the
ATI "video" sliders instead of adjusting at the display.
I'm using 4:4:4 full RGB
1920x1080 @ 59hz
and adjust the ATI "video" sliders via TMT3 and the AVS-HD test patterns
The Epson is set to Theater Black 1 and expanded color range
I watched some Blu-ray from harddrive (I Am Legend and i,Robot) and to my eyes this provided some of the best video quality I've ever seen through my HTPC, colors/contrast/sharpness/smooth motion even at 59hz,
in a word beautiful. When set to pass-thru the Yamaha doesn't even overlay the volume OSD so it appears to be a true pass-thru and it shows in the resulting video quality.
So far I've tried the HTPC and the Dish Network HD receiver. Switching is fast, say less than 3 seconds, and the audio has locked on every time with no drop-outs.
Audio test tones work well, I raised master volume to 0db and manually set all channels to 75db with a RS analog meter. I adjusted the subwoofers gain
control to approximate the same amount of trim the other channels needed to attain 75db.
I don't listen at theater reference level (0db) out of respect for my hearing.
I listened to the previously mentioned Blu-rays at -30db and the results in my small (23'x11.5') theater room were most impressive.
Dialogue clear and intelligible
highs clear but never harsh or fatiguing, perhaps slightly rolled off
bass REALLY strong, deep and well defined @ 80hz x-over
integration between speakers and sub sounded really, really good
At the -30db master volume setting audio peaks during the movies measured as expected at about 75-80db and the loudest bass at 85db.
This allowed me to enjoy power and detail of the lossless soundtracks for 3 or 4 hours without any listening fatigue whatsoever, and without using any dynamic range compression.
In short, when used as a preamp-processor I can't tell that this receiver is giving up much (if any) performance compared to the other, higher priced units referenced above.
In fact, I think it sounds better than the Onkyo which I've spent a lot of time with.
The Yamaha does run pretty warm on an open metal-mesh rack in my probably 80 degree room, about the same as the UMC-1 but not as hot as the Onkyo, so I may add some additional cooling.
It appears to only draw about 50 watts when used as a preamp-processor, compared to the Onkyo at 150+ watts.
In summary, my initial impression of the Yamaha is very positive and it looks and sounds like a keeper, especially when considering the low price.
P.S. The Harmony 890 remote control has a good set of codes for controlling the Yamaha, with discrete on/off, discrete inputs, etc.
Thanks so much for all of the input in this thread.