These numbers were chosen as an example, but isn’t as unlikely as it seems. These are peak levels taken from the listening position (9’) from a pair of speakers playing (2 speakers = +3dB) with some room boost, and C-weighting (accounting for most of the bass). That’s not filling the entire room with 100dB, those are peak readings at a semi-nearfield listening position in a near-ideal room for these speakers. And this represents probably less than 5% of my overall listening, and then for perhaps a side of an album. 95dB peaks would be a more typical *loud* listening session, still infrequent, with *no* 2.4 power handling concerns.
Even then, if that highest level is 105dB at 1m, that’s ~100 amplifier watts (if they’re 87dB@1W/1m), and my amp delivers ~500 watts per channel into 2 ohms with plenty of dynamic headroom. I now better know the limits of the limited midrange, and am comfortable with keeping volume and program material well within their comfort zone. I have never heard my amp compress, harden, and certainly not clip at any volume into any speaker load, which suggests I’m not intent on finding the limits of my amp or any guest speaker!
Rob Gillum tells me in ’destruction testing’ of the similar 2.3 coax development, they typically achieved 115dB SPL steady-state (not transients) before ’it blew apart’ (with 600W Krell monoblocks), and that 100dB peak SPLs from 2.4s should be reasonable in a 3000 cubic foot room (mine is 2500). FWIW, I have never blown a 2.3 coax, even though we have no reason to believe they are a sturdier design. Indeed, Rob says his current rebuilds of these drivers use more-modern adhesives and construction techniques that will increase the robustness of the 2.3/2.4 coax.
Half my coaxes were covered under warranty, and only one exhibited obvious signs of being driven beyond its excursion limit. More typically the lead wires fatigue from years of excursions (well within the driver's (motor + surround) excursion limits) and open the circuit. Rebuilding a coax every couple years is a whole lot cheaper than buying a speaker today that ticks as many boxes for me as my 2.4s!