I have trouble agreeing with you on that. In my system, in a room of 12.5' X 18' opening to a kitchen entrance and using three 15 inch Dayton subs, which have a sensitivity of only 87 dB, I've never had any of the QSC amp deliver over 30 watts to any of them. I play a lot of classical music including pipe organ music with some source frequencies going below 20 Hz.
I figure that someone must be playing music and movie soundtrack content at very high SPL and is sitting far from the speakers to require really beefy amps.
I don't disagree with you.
You know I have been studying and learning about speaker design/building... eagerly getting to the point I can start my first project, too! (I think I'm ordering my Router nest week!)
I will say, the QSCs I'm familiar with (the cinema ones, which if I recall correctly are the ones you use), are quite stout and stable down to 2 ohms. I would not expect them to blink an eye driving those woofers (which, thanks to you, I am looking at very seriously for my first Sub build!) and a whole lot more!
The more I've learned, though, makes me really question the electrical behavior of a 4-way speaker with so many drivers. 2 10", 2" 6", 6 tweeters for midrange array, and 1 for the actual high end.
Without any third-party testing, we have absolutely no information on XO points, cabinet tuning, real electrical behavior... Nothing.
If most 3-way designs do in fact introduce challenging phase and impedance issues (which it certainly seems like they do (not meant to be an absolute, but let's face it, there are a lot of such designs out there) then what is happening here in this specific instance?
On the other side, I look at some of the Gravesen designs that are 4- and 5-way builds where he uses (now) the Hypex Fusion plate amps to run one or two of the lower drivers, allowing the passive network to run the other 2-3 drivers.
We all know there are many ways to skin a cat... some more useful and efficacious than others, to be fair.
Based on my interactions with Eric at Tekton, I want to believe that the DIs are suitable for any mid-range AVR to drive. I quite enjoyed our conversations over the few months we were talking, and I am still interested in hearing his work. At the same time, I was reminded of Clifford: "It is wrong always, everywhere, and for anyone to believe anything on insufficient evidence.”
If he would publish measurements, that would be a start. If he would allow others to test and publish, that would be ideal. Which only leads me back to the question of what really went down with New Record Day and their measurements... why they were pulled down, and why I still know nothing that I didn't know 2 winters ago?
Thanks, Verdi!