The (Un) "Official" Yamaha 765 Thread

another rx v765 owner here. i've had it since may and run a set of c-series energy speakers off of it. i have my c-500s hooked up to an adcom 2 channel amp, but the 765 does a great job running my center and surrounds. about time there was a 765 thread as opposed to the 665...

A better approximation is from looking at power consumption, IMO. Rated specs are misleading for reasons I have described in the FAQ

RX-V665 listed power consumption
* 270 Watts; 320 VA; Max (general model) 490 Watts

RX-V765 listed power consumption
* 400 Watts; 500 VA; Max (general model) 590 Watts

Looking at those figures, assuming the two consume the same power for operations other than the power amp, assuming 50% amp effiiciency, I think it's safe to say the 765 has at least 50 watts more output power total (not per channel)

It's simpler than it seems. I might elaborate a little though, because it's a topic I have a lot of interest in.

The FTC set rules for rating receivers and amplifiers to prevent misinformation. The FTC loosened up the rules a bit, and did not change the rules much when more than two channels became common.

Allow me to quote the FTC themselves -

"Under the Rule, all "associated channels" of an amplifier must be driven to full rated power simultaneously during the power measurement tests. Accordingly, the Commission is soliciting public comment on three alternative methods for designating "associated channels" for multichannel receivers and power amplifiers."

In other words, associated channels is not defined for receivers with more than two channels.

So, of course manufacturers will tend to choose something like the L/R amps to rate their amplifiers. Using only two of five or seven amps allows much more power from the power supply to be available for the L/R channels.

Other factors which make a difference -

* Bandwidth - 1khz va 20hz to 20kzh will give a higher power spec
* Impedance - Receivers rarely give a 4 ohm spec; It would be embarrsing to many if they did, because the power supply can't really cope. Not to mention many receivers would go into thermal shutdown or over current shutdown to protect themselves from the high load (low impedance); I mention it because 8 ohm speakers are not simple 8 ohm loads. It's hard to find where anyone has done scientific testing, but many people feel that some 8 ohm speakers are significantly harder to drive than others, and some amps will do a better job due their output impedance (lower means better damping,) and the ability to supply power better into real world speaker loads ( often referred to as high current capability.)
* Conservative vs. optimistic; By measuring at higher distortion such as 1% THD or even 10% THD, a higher power spec can be obtained; Sony is one of the worst offenders here

Is an all channels driven spec important. Not necessarily. As people will tell you, not all channels are peaking at the same time. But it does tell you something about how much power the receiver really has simply because the rated specs are useless in many cases, IMO

So, what can you do?

* Read reviews with benchmarks
* Look at power consumption
* Look at receiver weight; Yes, I know some people hate this, but there is a strong correlation between power output and weight in most receivers; For class D (such as the Pioneer SC series) which are much more efficient we are no longer comparing apples to apples, so take that into account

Yeah, it's not an absolute rule. Some receivers use more metal than others. Or vary for other reasons. There is no doubt though, the the power transformer is responsible for a good chunk of the receiver's weight.

Bigger transformers can likely handle more power, and likely have better voltage regulation. And they are heavier.

If you really are concerned about power, look at every piece of information you can get your hands on to make the best determination.

Sorry to pollute the 765 thread, but I felt this link to be interesting. The FTC solicited responses from the industry regarding the current rule.

Few responded according to one FTC report, but Sony did respond. Specifically, they felt there was no need for an all channels driven measurement. Of course they sidestep the fact that only testing a few channels can be misleading. Or the fact that they will give the rating as 110x7 in literature which CLEARLY implies 770 watts. In fact, Sony has been known to SAY 770 watts in that case even though most of us would call that LIE.

Anyway, here's the link

http://www.google.com/url?q=http://w...lAw_voilzT1EmQ

I find that very odd. I would assume you would have to unplug the receiver to disconnect all power from it. Are you sure it's really and truly powering down completely?

Using a Kill-A-Watt meter, I've seen my 765 pull 520w from the wall. Volume level at 0. I never looked at the VA (could not stand it in the room) but I figure it was pretty high. I also never took it to +16 or anywhere positive.

I know the 765 has way more power than I need for my room, and would work for something 8 times the size given the right speakers.

I've now had mine for well over 2 weeks with no display to look at. I'm expecting my pj back any day now. Then it'll get a good workout I'm sure.

I would contact Yamaha support. They will likely be useless, but I can't explain the behavior you are seeing.

Volume setting tells you nothing about an amp's power. Volume sets gain. Gain is not the same across all receivers.

Max power is dictated by the power supply and/or any circuits which limit the amp's power.

I have never seen that high of power draw in my testing. The amp was likely clipping at that point.

It's nice to know the power supply can draw that much power without shutting down though.

My receiver's (Z7) max power draw is rated at over 1000 watts I think. I don't think I have ever measured more than 200 watts of power draw.

That is different than standbye on the Z7 where you can select a fixed input such as your TV source. Or you can change to the proper input, then put the receiver in standbye mode.

While your interested in how much power can be consumed, I'm interested in the opposite: Idle and Standby power. I have become very sensitive to how much power devices are taking when turned off. Can you measure the standby power and idle power (unit on but not sound muted). I have been comparing this to the Onkyo's and Pioneer. I eliminated Onkyos due to their excessive idle and standby power.

I also have heard that v665 owners have to turn up the volume knobs to much higher dB levels than their previous Yamaha receivers. How would you compare these receivers to your past? It -20dB roughly same volume level?

Thanks

Once again, volume setting has nothing to do with max power. I emphasize nothing. Really.

It's about gain, not power.

Input a .1 V peak to peak sine wave into an analog input into two receivers. Set both their volume settings to -20 dB or something like that. Neither will be clipping. But their volumes may not be the same. Why? Gain. The gains may not be identical. Gain has nothing to do with max power. It just tells you how much the input signal will be amplified.

The only way to really measure max power is to input test signals, and compare them to the speaker outputs to measure THD. At some predetermined THD (there's no standard), say .1% THD, measure the output power into an 8 ohm dummy load. The power will depend on what frequencies the test signals are at, and how many channels are driven.

I'm gonna intentionally avoid some of Michael's points, because he's right, but in these situations people are describing, there's more to the story.


And here's why I am avoiding his points. On my system, I feed it with an HTPC. I've had my receiver for a few weeks now, but it so happens my projector died the day before it arrived. So I've not used it much.

When I first started with it, volume from my SP/dif was anemic. I was turning the volume to -10 for general listening levels. It was so bad, I sometimes approached 0, but the hissing in very quiet passages was quite noticeable. I knew something was wrong. After messing with it a bit I asked on the HTPC forum and Renethx fixed me up with a fix. Since, I set my default-on-volume to -45 and run most of my movies around the -30 to -35 range. Some even as low as -40 now. It was the level of my output that was hosed up, and my ATI video card HDMI was a joke. His fix with ReClock worked wonders and I don't even know how.

Music I run in 7 channel enhanced mode, and if I get much higher than -30 there, it's really crank'n. Beyond what I call comfortable listening and I've been a metal rock'r since the early 70's listening to some pritttt teee loud stuff. Gets me thinking back to my first receiver, a HeathKit. What a machine! I still own it I think, might be on the attic.


I had to go outside to tell if it was or not, I was curious. It sounded fantastic from outside the house. Even my JBL Sub wasn't clipping. I have no neighbors to speak of and it's a good thing.


How large a drivers are you pushing and how many? This was a test now, I would never listen to this thing there and certainly would not run it like that for long. I think I was playing Firehouse - Lovers Lane when I did this in 7 channel enhnaced mode. Not playing a 7.1 DD movie. I think the content need to be pretty strong to pull that sort of power. The NY Symphony Orchestra isn't gonna get it done.


Idle Power on mine is about 42 W. Standby is hovering at 0 - 1. So, I am assuming that means .5w. WAY better than the Kenwood it replaced which pulled 11 or 12. Now, I should qualify these numbers and say to you that I have no display. My red light is off as I speak, so perhaps this means the receiver is really off, not in standby. If that's the case, I'll have to wait till I have my projector back to get a good number on that. Suffice to say though that no matterer what it does, the power it uses is less than the 12yr old Kenwood I had. Idle on that was 49W.

I should also say, normal listening volumes for me have the unit pulling about 55-80 watts, depending on what mood I'm in. I seriously doubt I'll ever have guests here and have it hit 100w from the wall. I also seriously doubt I'll have it pulling 200w for any period of time. 500 is just insane. For anyone who'd like a good laugh, my cat lay sleeping on the floor in the next room during that test. He's heard some metal before!


My Kenwood VR-307 I think it was, had a volume scale much like this 765. It stopped at 0 though. I'm gonna say that receiver also rated at like 90w/Ch x5 showed near exactly the same volume levels to be comfortable. I never got near 0 with that, and I won't with this. -10 was blasting, and -20 was inordinately loud. -30 was all you wanted in a movie like Transformers or Independence Day. -35 to -40 was overall about normal.

I can't wait to get some new speakers for this thing. I have a few picked out but I have been spending money like a drunken sailor lately and simply have to stop. I would think that in the next 3 months or so, I'll have a new set of fronts and front presence speakers for this baby. If I get the fronts I'm looking at, guys on the west coast might be able to hear this baby!

found this for receiver for 360 and the pioneer 21 for 430 , dont know which one to get ! could this receiver fill 30x15 or 25x10 rooms? i have pretty efficient speakers 89-93db !!! also could i use zone 2 with a amp for a pc karaoke setup?

I got my 765 and Definitive Technology ProCinema 800 5.1 speakers a couple of days ago. Finally got it all set up last night. This system replaces a 20+ year old fairly high end 2.0 system - Luxman R-117 receiver and Infinity SM 150+ speakers. The wife is thrilled to lose the big speakers.

I have not run YPAO yet and am very pleased with the sound. I DVR'd the recent rock and roll hall of fame concert on HBO and watched some of it last night and was really happy with the sound. Some of the club effects really enhanced the music, but I always seem to go back to no processing. I also watched a bit of Hancock blue ray and it seems to be handling the special effects sounds quite well.

My display is a Sony KDL-52V4100 LCD. Blue ray player is Sony BDP-S550. Cable box/DVR is Motorola forget model # from Comcast. The display is only connected to the 765 by HDMI. Blue ray is plugged into HDMI 1 and works as expected. I also have a 400 CD changer connected optically that works as expected and sounds very nice.

The cable box does not have HDMI output. I was using a DVI to HDMI cable with a seperate sound connection directly to the display before. Trying the same cable with an optical connection for sound did not work with the 765. The picture would flash on the screen for about 1 second and then blank; after a few more seconds the display would come up with its "no input" screen. Sound from the 765 was fine. I could not find any settings that made it work. I have the cable box connected to the 765 with component video and the optical sound connection and it works for the picture. I have it upconverting to 1080p and it looks either really nice or OK depending on the channel. There is no sound being passed to the display in this configuration (yes the output in the 765 is set to TV+amp). The sound out of the 765 more than makes up for it. If my local Comcast office ever gets any new DVRs with HDMI that should make everything better.

That was a long first post. I hope it helps another noob with this fine receiver get things working to their satisfaction.

I got an updated cable box with HDMI output. It's a Motorola DCX3400. When connected through the receiver it keeps resetting itself to 720p whenever the display is turned off. It seems to be a known issue with this HD DVR - (can't post URL yet) []www.avsforum.com/avs-vb/showthread.php?t=1161840

Receiver settings don't seem to matter. If the receiver is on it keeps the settings until the receiver is turned off. Pass through with the receiver off works, but will revert to 720p with a power cycle of the display.

Connecting the cable box directly to the display it keeps whatever settings I have. Leave it to Comcast to screw up my new HDMI switching receiver.

For now it's hooked up from cable box to display with an optical connection to the 765 for sound.

Common issue. I can tell you why I think it happens, and why there's not much you can do.

Whenever you turn the power to the TV off, something causes the source device to query the attributes of the display device. Which no longer exists, as it was turned off. So the cable box resets to some default.

The only ways to fix this -

* I am told some receivers don't cause cable boxes to reset; I would guess they do something different than Yamaha receivers do; perhaps they remember that last known display EDID
* Get the Gefen HDMI detective; This somewhat expensive box would run you slightly over $100 and would "spoof" the display's EDID info; I have one, and it does work
* Ignore the problem
* Use component video rather than HDMI

Thanks for that. I'll look into the Gefen HDMI detective. I'm currently using the "ignore the problem" method. Hopefully Motorola/Comcast will have a fix, but I'm not holding my breath.

Power Consumption when in standby with HDMI Passthrough.

For those above who were interested I read in the manual that the typical power consumption when passing an HDMI signal is between 1 and 3 watts and depends upon the signal being passed. Using my meter I verified those numbers to be accurate. Mine pulls 2w.

For those who reviewed the DVD upscaling and say it's terrible, unfortunately I have to report they are correct. Since it's not a big issue to me I really don't care. But it was pretty disappointed to see what it does to Component and Composite signals.

Hello to everyone! Merry X'mas!

My 765 got delivered on 12/23/09 and since then, I was trying to get it to show the lossless decoders, i.e., DTS-HDMaster or Dolby True-HD to show on the display. Any tips on how this will happen? It only shows DTS or PCM
If I can't get this to happen, it will go back to seller.

My set up.
Panasonic BD50
1) HDMI Audio = on
2) Audio Priority = Quality or Custom
DTS-HD = Bitstream or PCM
Dolby True= Bitstream or PCM
Secondary Audio = Off or Off

I appreciate any response.