I was referring to the controls on my integrated receiver.

Mine also have a single post on the back with a red tag that reads "Do not connect. Intended for a future sonic virtualizer.". This post has no internal connection...oops!

So they followed their own advice and didn't connect.!

Bosen. It's bosen. In German, you'd just add an umluat to make it Böse, which translates to any of the following: devil, evil, diabolical, annoyed, angry, exasperated, pissed off.... You get the picture.

Anthony, assuming a "need for a more powerful amp" if you get the M80s may lack any factual basis. Since the M80s have a slightly above average sensitivity(requiring less power than the M60s, for example)they and other 4 ohm rated speakers of similar sensitivity have been operated for years with modest receivers without difficulty. You appear to more concerned with the rated impedances of speakers than the power they actually require in typical home operation.

I'm just concerned by the conventional wisdom that plugging 4 ohm speakers into an amp that's nominally rated for 8 can result in the amp getting very hot, shutting down, clipping, etc. I don't have any firsthand knowledge in this arena and want to be sure that if I plunk down $500+ for an AVR that I'm getting what I need, and won't damage my shiny new Axiom investment.

You won't damage the Axioms, as you said it is the amp that gets hotter etc but only if you drive the speakers hard. You will still only need 1 watt to achieve 91-95db depending on the room. That 91-95 is about as loud as most people go, the rest of the power/watts the amp has is used for peaks in the material you are listening to.

I dunno... you could induce clipping if you turn it up too high, which ain't good for speakers.

That said, I'm using an H/K 525, rated at 85WPC for 4 ohm loads to drive my M80s.

I am woefully ignorant of the technical details of how much power is required to drive the 90-95 db sound level or how hard a receiver must work to drive the M80's. Most of the posts I read in here state that receivers like the Denon 3800 or 2800 series or the Yamaha 1800 and up. I just bought the Yamaha RX V663 AVR as a means to pick up HDMI for a future Blue Ray and to pick up the latest Dolby capability. The 663 is rated at 95 wpc for 5.1 - I know that this type question gets asked ad nauseum - but would the 663 drive the M80's?..........Rob

How loud are you going to play them?

Every room is a bit different but you can use this calculator as a guide to estimating wattage required. It's near the bottom of the page after nice explanation of the terminology used.

Allegtro - Amplifier Power calculator