which excels at Rock and Roll

I've heard the Marten Oscar Duos and definitely preferred them to my Fritz, which I loved, and then auditioned the Parker Duos and the mids on those were amazing, so that's what I went with. 

As for agnostic speakers, I've had a number of different speakers in my system, including Harbeth Super HL7's, and while great sounding for many smoother genres, those Harbeths are not designed with rock music or reggae in mind. 

I have a MA7900 McIntosh int amp @200 wpc and a pair of reformed JBL L100 T's reconditioned , refoamed and Crossover Chef crossover's with a room your size. With a good high end SACD player like my Denon DCD-A110 classic rock will transports me into the next dimension 

I had a pair of DeVore Gibbon 8 speakers.  They are definitely NOT for Rock.  Jazz and classical they excel, rock NOT.  I drove from RI to Annapolis Maryland and back in one day to pick them up a couple of days before New Years in 2008 or 2009, my memory isn’t that clear.  Hooked them up the next morning as I got home after midnight and what a huge disappointment.  I really wanted to like them, added a sub but they were just too soft for Rock.  I kept them for a little over a year but ended selling them for what I paid.  They were gorgeous speakers but didn’t play Pink Floyd well at all.  One of my systems is strictly for Rock and I use the JBL L100 Classic speakers and a single SVS subwoofer.  I drive them with a 200wpc McIntosh integrated amp.  Match made in Heaven.

Those Acora MRBs have sounded sensational at shows.

I didn’t read all the comments but if you want a REALLY good rock that’s also a really good speaker in general, check out the Volti Rivals. I owned & enjoyed some good Dynaudios & have heard many of the other suggestions mentioned many of which are quite good in different ways but none can do rock like those Voltis. Additionally, you only need a good 20-30 watts to make them sing at almost any volume in a big room. They truly sound like live music & not hyper detailed hifi.