Originally Posted by ss9001
In general, I agree with Theresa.
the specs are looser, instead of 20-20K rms type ratings, we increasingly see watts @1Khz and even higher THD, 0.5 & 1% THD is not uncommon.
Plus, instead of 5 & 7 channels, we have 9 channels! power supplies are not getting bigger, so when more channels come on line, under load, power/channel has to go down.
in general, top model receivers have general power ratings in the 140 -150 wpc range and that hasn't changed much in years.
the exceptions to this were the mighty Denon 5805, the 5308 and Pioneer's SC-09. the Denon 4520 & Pioneer SC-68 do hold up well but still cannot & do not compare in max power capability with multiple channels driven to those former flagship models. the SC-09 could maintain very close to 7 X 200 wc @ 8 ohms with a 1400 watt power supply & that's pushing 80-90% efficient class D amps, not the typically 50% efficient class A/B amps used by Denon/Onkyo/Yamaha & everyone else.
the power supplies in new models top out at 770-810 watts & with more channels there's no way they can equal what the top receivers only 5 years ago did.
this is from bench tests done by a German review site that's on YouTube. the video has a very loose & not good translation if you want to listen but I took several screenshots of his comparisons of the 4520, SC-LX86 (=SC-68) & Onkyo 5010. he ranks the 4520 #1 overall, but in raw tested power with multiple channels...it comes in #3. and that's due to smaller power supply. @2 ch & 8 ohm his test was 150 wpc. but @ 5 ch & 6 ohm, the 4520 sags to 35 wpc.
the real good news for Denon fans is that his bench measurements show their amps are "cleaner" than Pioneer's when pushed to clipping. and he rates the Denon as best in overall audio quality but Pioneer does win in 5 ch power.
from hollywoodzuhause review Pioneer Onkyo Denon.doc 1379k .doc file
Given the translation issues, it's hard to figure out exactly what they tested. Their figures for the Onkyo 5010 are particularly interesting raising the possibility that they have different current limiting circuitry built into European models. Your attached chart shows 60wpc with 5 channels at 8 ohms and 30wpc with 5 channels at 4 ohms for the Onkyo - Home Theater tested the one step down Onkyo 3010 and did better than 110 wpc with 7 channels driven into 8 ohms.
It's also interesting that they do not show wpc with 5 channels driven into 8 ohms for the Denon so it's even harder to draw a reasonable comparison as they show only 6 and 4 ohm figures.
On the other hand, the Pioneer seems somewhat in line with the results Home Theater achieved with the SC-68 - the SC-68 did better in their tests with 2 channels driven and a bit lower with 5 channels.
In any case, hopefully we'll see something from Home Theater in the near future but judging by the strange results for the Onkyo 5010 I wouldn't treat this lab test as the last word on the performance of these AVRs. One thing that was obvious to me based on this review was that the Pioneer and Denon are clearly better looking than the Onkyo.