Well I finally gave up at any attempt at decorum (like I had any to begin with) and bought a 45" tall 19" equipment rack. It was hard to find a good one and they aren't cheap. Anyway this allowed me to move all of my gear closer to the speakers and ditch the 30' cables. Got some silver wires for the high, copper for the bass. Modest improvement, but not huge.
Next I was able to reposition the speakers with the new cables. Huge difference ! I put them about 4' out from the back wall, about 6-8' apart, and about 6' separation from the side walls. Fantastic improvement in imaging and sound, about 2x overall gain in sound quality. But the speakers are right in the freakin way in the middle of room, oh well.
The Lexicon/Bryston arrived. I am planning on using it to drive the woofs eventually, but for right now I just used two of the five channels to replace my old HK amp on the Neos/FST. Another huge, eye opening surprise. I've got 500wpc@4ohms from the QSC driving the bass, and 200 wpc@4ohms from the Lexicon driving the mids/high and I can still EASILY go into clipping on the Lexicon, a bit more difficult on the QSC.
The only reason I would know this is that both amps have clip indicators. But I can actually hear the distortion from the mids when the Lexicon clips, if I am watching the indicators. It is no wonder the poor old HK didn't sound too good. The Lexicon sounds MUCH better, I'd say a 2x improvement in the overall sound, as long as I keep the volume at a level where there is no clipping.
Since I am pumping a max of 700wpc into these guys and can still easily clip the amps, it is no wonder that quad 'Zillas sound so damn good. I really suspect that most RM40 owners are underpowering their speakers.
Thanks Julian for the heads up on the power, but I didn't realize that the mids would be so hard to drive. It looks like this may make the use of tubes to power the mids prohibitively expensive, as I wouldn't be comfortable with any amp less than ~200wpc for the mids. I may stick with SS on the mids and use a modest tube amp on the FST, don't know yet.
Anyway, the sound is starting to approach downright scary. I don't know if I can stand it if it gets any better, my head might explode.