Most high-quality loudspeakers are 4-Ohms

Any 4 ohm little monitors out there that can out do the 15 ohm Rogers LS3/5.♫

Swampwalker, I suppose for the most part we actually do agree. The Vandersteens aside from their selfpowered subs have a minimum impedance range of 2 to 5 Ohms. As for the others, yes they are generally considered "high end". I just haven't heard any high minimum impedance speakers that I would care to own, so IMHO I guess I wouldn't consider them "high quality" regardless of the craftsmanship, marketing, etc. involved. Others are of course welcome to disagree. I think the OP's question has more merit than some might at first assume.

16ohms or or so can sometimes be better sounding. And a easy load for most all amps. 4 ohms is easy to design for try keeping a 3 way or 4 way loudspeaker 16ohms not a easy design chore. But to be fair 4 ohm designs can sound great as do 8 ohm or 16 ohm. Just depends on total design and system said loudspeaker will be used in. In loudspeakers its the design and parts used that maters most the ohm loads more a issue when selecting amplifier.

JohnK of course your point begs the question; does a speaker designer have to make compromises in order to make speakers work with higher impedances?