Originally Posted by Eldiablos
I noticed the power consumption of the 4311 is 780W. I also have been looking at the Onkyo 3008/5008 and their power consumption is 1060W. Is this big of power discrepancy something I should be concerned about? As in does this mean the Onkyo has beefier amps?
It doesn't necessarily mean the Onkyo has beefier amps
, though it likely means it has a bigger power supply. That could translate into more power with all channels driven. Obviously, if you factor in a typical class AB amp power of 70%, you aren't going to get 9x140wpc with only 780w. You'd only get about 60wpc, and that's before factoring in power consumption of other components, like the DSPs. Personally, I'm not overly concerned with that. When you start adding more channels, that doesn't mean you need more total power. Sounds that are redirected to the "new" channels (like height channels) should
be equally reduced from the channels they were originally encoded into. If they weren't, that would mean those particular sounds would represent a higher emphasis in the overall soundfield than the recording engineer intended. You still want each channels to have the headroom for scenarios where sound IS focused at one point, but not having that much power on tap simultaneously isn't a big deal in my book, considering how many channels the soundfield is broken up into these days.
Comparing Onkyo power consumption to Denon is a little trickier. Onkyos are known for producing a lot of heat (I know, I have an 875), and from what I've read that hasn't changed in the newer models. Hard to say how the 4311 will compare, but traditionally, I don't think Denons are known for running as hot as Onkyos. Heat HAS to be the product of inefficiency (unless, of course, you are designing something with the specific purpose of heating). Whether that means Onkyo's amps are less efficient, or their DSPs consume more power, or something else, that heat represents power that isn't making it from the wall socket to the speaker terminals. But on the flip side of that, it's also possible that the Onkyo amps and Denon amps simply have a different efficiency curve. Perhaps the Onkyos don't "idle" as efficiently as the Denons (like comparing a class A amp to a class B amp), but have similar efficiency at full load. If that were the case, the the Onkyo could waste more power in typical operation, but have the same efficiency at full load.
In short, it's nearly impossible to know exactly what impact the different power consumption numbers have on actual power capabilities of the two receivers, without someone doing some bench testing. But most likely, considering the logarithmic scale of power vs. audible output, and the fact that it's spread between so many channels, the real world discernible difference in output power between these two similarly classed receivers is likely to be relatively minor.