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So once again i ask, why would anyone buy a four thousand dollar top of the line Elite receiver that is officially not supportive of 4 ohm speakers?
You would think for 4 grand they would build an amp that was capable of such a feat.

I just don't know about Pioneer anymore. But they've made such great strides in the DVD-RW fields...

Sushi, your information about the 912 would certainly disappoint someone who was considering it based on a presumed equalization ability. Without this it would be similar to the HK models which automatically set speaker levels, and I agree that this would be a relatively minor attraction. I assume that you got this from Tokyo and that the info would be more reliable than what was at least a misleading Pioneer press release which spoke of the MCACC success in the Elite series and strongly implied that the same abilities would be offered in the lower-cost models(although I did note that the release didn't specifically mention equalization). It's curious then what the two "manual" models offer, since all HT receivers have provisions for manually adjusting for speaker distance and levels.

chesseroo: Well, with regard to the official spec, my understanding is that relatively few brands support 4-ohm speakers in their (even high-end) all-in-one receivers anyway, with Onkyo being one of those few that officially mentions 4-ohm speakers in the spec. Correct me if I am wrong, but I cannot find a mention of 4-ohm speaker support in the receiver specs/manuals from Pioneer, Denon, H/K, Yamaha, or Marantz.

That said, I do agree with you that the overly conservative setting of protection circuits in Pioneer Elite receivers is, at best, very strange, especially in their more expensive models. According to reports from people who had their Elite "fixed," the receiver seems to be capable of driving their 4-ohm speakers just fine after the fix. Just paraphrasing what you already said, I guess people who want a no-brainer support for 4-ohm speakers, need a peace of mind, and have several grands to spend on amps (not me ) should really go for separates rather than one of these higher-end all-in-ones.

JohnK: I got the info on D912 from Tokyo, and they were very articulate about the point. Indeed, the PR does not specifically mention equalization, which triggered me to send my inquiry in the first place. This PR could serve as a text-book example of misleading advertisement. Oh well...

Cheers!

Actually Sushi, if you look at the dynamic power listings for the Denon 4802 (a model i was considering before i got the Onkyo) and the Yamaha RX-V1, they are 'rated' for 4 ohm loads (2 channel) and both models list ratings down to 2 ohms.

I nabbed this from the manual specs:
Denon 4802 170W-8 ohm, 270W- 4 ohm, 350W- 2 ohm
Yamaha RX-V1, 150W, 180W, 240W, 340W at 8, 6, 4, 2 ohms

I could not find this same info for the H/K, Marantz or Pioneer (although to be fair i couldn't find a user manual for Pioneer).

I may not consider running a 4 ohm speaker all the time with these models but it certainly would depend on how the 4 ohm rating was assessed. If the speaker has several spikes down to 4 ohms but really averages about 5 or 6, then i probably would not be so concerned. If the speaker was more an average of 4 ohm with spikes below that, i would probably look alot closer at getting separate components.
I'm sure that several of these amps/receivers should drive 4 ohm speakers just fine (my Onkyo did) but i agree that the Pioneer protection circuitry might be a bit on the overly conservative side. Perhaps it is because their amps get hot enough just powering 8 ohm speakers that they NEED the protection circuitry more so than some other cooler running brand names.

chesseroo,

Thanks for correcting me a big time; I certainly did not look at the user manuals of Denon or Yamaha (are they available online?). I may have judged these models based on the brief catalogue specs and the rear panel photo on the web site -- the rear panel of Denon does seem to mention "6-16 ohm." At any rate, the manual specs you cited surely sound admirable for an all-in-one, especially Denon's, which are essentially linear, meaning that only the swing voltage, not the current, of the final stage is the limiting factor. I would strongly suggest the marketing department of these companies do mention and promote these specs in a more visible way!

I might sound like crazy or simply stupid when I tell you that, after this much of Pioneer bashing by myself and others, I still have not dropped the Elite line from my candidate list. But despite the rather negative comments by Alan about automatic equalization in general, I feel that, judging from owners' reports, MCACC may well help in my situation... Well, if I ever go for one of the Elite receivers, I will probably keep my Adcom GFA-555II power amp for my 4-ohm Hales speakers (the amp is huge and heavy for its mere 200W x 2 output, and surely cool-running LOL).

Cheers!

Interesting post. I recently started setting up a HT system. Have the HDTV and got a great deal on the Onkyo sr800. Now I need the speaker system to finish it out. Yes, this receiver states it is capable of 4 ohm operation with a setting change, but I don't really know how that would affect its operation relative to sound quality, volume, etc. So to stay within the know area of the amp, I have been considering the M60s (8 ohm) over the M80s (4 ohms). Where has my thinking gone astray ??

Dynamic power ratings are very misleading, don't know why more companies don't give RMS values which are more representative of the true capabilites of the amp.

The M80 is a 5 ohm load, but there is still enough 'dynamic range' to trigger my onkyo 787 protection circutry on occasion. SO much for Onkyo's WRAT (Wide range amplifier technology)...another useless marketing gimmick.

redget,

chesseroo would give you a more definitive answer, but I suspect that the amp's impedance setting only changes the stringency of its current protection circuit. You can certainly experiment with both settings using your existing speakers, to see if it changes the sound quality at all.

That said, and given that your Onkyo officially supports 4-ohm loads, I would not consider the impedance rating as a primary factor in choosing between speaker models. Moreover, I understand that the M80s are more efficient than the M60s, which will reduce the amp's actual workload.

Cheers!

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Uh-Oh, here is an Onkyo owner who has been able to engage the protection circuit with the M80s... Well, I do not know what to read into anymore... After all, a total rated power of over 700W was simply unthinkable from relatively compact all-in-ones 15 years ago. It may be that we are just expecting too much on those poor receivers.

As amer stated:
"Dynamic power ratings are very misleading, don't know why more companies don't give RMS values which are more representative of the true capabilites of the amp"
This is true but the dynamic power rating should not be considered an absolute value for what speakers can be used on that amp. I read dynamic power readings as the power capabilities that the amp can handle but for short bursts or spikes of a heavier load.
I still prefer to read the RMS values of an amp and i would put more confidence in running a 4 ohm speaker for an amp that is rated with 4 ohm under the RMS spec. Most of the Denon, Onkyos , etc. usually have an RMS value of 6-16ohm with all channels driven and sometimes they throw out a spec like 4 ohm (xx Watts) 2 channels driven.
They market the very limit of the amp to make it sound like the amp is capable of such a feat but again, as amer noted:

The M80 is a 5 ohm load, but there is still enough 'dynamic range' to trigger my onkyo 787 protection circutry on occasion. SO much for Onkyo's WRAT (Wide range amplifier technology)...another useless marketing gimmick."

This is why i threw our my earlier comment:
"I may not consider running a 4 ohm speaker all the time with these models but it certainly would depend on how the 4 ohm rating was assessed. If the speaker has several spikes down to 4 ohms but really averages about 5 or 6, then i probably would not be so concerned. If the speaker was more an average of 4 ohm with spikes below that, i would probably look alot closer at getting separate components."

Unfortunately i've read about amer's problem with several other people who own the 787 model. Since i have the 797 model which does not have a cooling fan, i'm guessing that Onkyo changed their heatsink or other internal components to make it a bit beefier. I've run some 4 ohm Kefs off this receiver without any problems or auto shutoffs.

All that aside, i have heard Pioneer receivers, i like them and their onboard toys and if i soley used 6-8ohm speakers i would look at them more seriously as a contender, just as i did last year.
Certainly if you already have a separate amp for your Hales, then just use the receiver as the pre-amp for processing and let the Adcom handle the power as you seemingly plan to do.

In that case, i don't think the power specs of the Pioneer would matter quite so much in your decision to purchase one.
I'm guessing you are not interested in finding a separate pre-pro and amps for surrounds eh?

I am probally being to hard on Onkyo here. I think the problem is local to the 787 and the corresponding Integra model of the same vintage.

All that being said.....if Boeing ever comes out with a plane called the 787....I'm not flying in it......lol.

I will be heading down the separates route, and looking for a good surround pre-amp processor able to handle all the latest HT formats (ie: Dolby EX, DTS-EX Discrete). Any recommendations?