I don't see how you arrive at that conclusion. As you say, the SC-1522 and Onkyo 3008 are neither given FTC ratings at 4 ohms, but Pioneer does give continuous power ratings for 9 channels at 4 ohms for the SC-1522 while Onkyo does not give such ratings for the 3008. That's a fact.

Maybe the impedance ratings are unimportant, but that was the subject of discussion, wasn't it?

Basing your argument on "ratings" is like saying how fast a new car can go based on the highest number on it's speedometer. Some cars will barely hit 75% of the speedometer total, others will bury the needle. All will get you where you're going at safe speeds.

I think the point folks are trying to make is generally...
For sure, some cars will perform safer at dangerously high speeds than others. However, most drivers (listeners) don't need to drive at dangerous speeds (dangerous listening levels) so thier non-sports car (most competently designed amps) will do fine for thier purposes.

I've run a Denon 3312ci, Pioneer SC-67, and an older low end Pioneer Elite model with the following speaker configurations in parallel. Currently it's the Pioneer SC-67.

Left Channel: 2 M22's 8 ohm each.
Right Channel: 2 M22's 8 ohm each.
Center Channel: 1 M22 at 8 ohm, 1 VP160 at 8 ohm.

Never had a problem. I'm not sure if an M80 would draw more or less current/wattage/whatever than my current configuration.

Oooooohhh, Murph made a car analogy.

Somewhere, a co-worker is warming their hands on the steam coming out of Ken's ears.

Shhhh, you weren't supposed to reveal why I did it!!!

I don't know what you think I'm arguing. Several years ago, I had considerable hesitation buying M80s when I could not find an affordable receiver which was rated to drive 4 ohm speakers. Maybe others had that problem, too? I said above, "Perhaps with these new Pioneer receivers that are [rated for 4 ohm operation], the M80s will become more popular." So, is this what you are contesting? You think that the audio press's mentions that the Pioneer's new D-class amps can drive 4 ohm speakers will not increase the popularity of 4 ohm speakers?

There's a ton of receivers that will happily drive 4 ohms. I've used H/K AVR525 and currently use an Onkyo 890. Didn't pay more than $600 for either of them.

Screw this "listening to music" and "watching movies" stuff; I'm going to go read Pioneer manuals and press releases for a hobby now.

Greg, I don't know what you're arguing, either. Everyone is absolutely delighted that you've had a great personal experience with the Pioneer receiver and your M80's. I like to hear happy stories. I think we can learn a lot from each other's experiences.

I just disagree with the premise that a current marketplace dearth of "receivers rated at 4 ohms" is a barrier to people buying M80's.

First, I don't necessarily agree that "most" receivers aren't rated at 4 ohms. I haven't done the research. I don't have the data. Second, I definitely don't think that particular rating matters. Virtually any big-name, mass market receiver is going to drive M80's (and nearly any other speaker) to unsafe volume levels in a normal-sized room. Third, I don't know how you could reasonably project that a significant number of prospective M80 owners share your preoccupation with that particular rating. Finally, at least some M80 buyers are going to already be committed to separate amplification rather than restricting themselves to using only a receiver.

So, I guess we're down to you saying "this 4 ohm rating really matters a lot" and several other folks saying "this 4 ohm rating thing really doesn't matter very much".

I do sincerely hope you enjoy your system. I'll bet it sounds really wonderful.

I hooked up my 80's to an old Radio Shack Optimus stereo receiver I still have, sounded great.

The impedance curve is not the whole story of a speaker. The M80's are very efficient at 95db 1watt/1 metre and has only a few dips below 4 ohm,very easy to drive. Now look at a set of magnepans, they have almost a ruler flat 4 ohm impedance graph and 83db at 1 watt/1 meter now thats a tough load to drive. As stated most any modern amp will drive the M80's without trouble. If sustained ,extremely loud music were being played,then a person may want to add some active cooling to protect delicate electronics. My experience is that the bulk of the movies out there only require short bursts of power for action type scene's not sustained power for the whole movie. Also the bass requires the most power from the amp and most if not all of us use a powered sub to take the load off the main amp. I dont see 4 ohm being a requirement to own a set of M80's imho.