I can't really make any real-time impedance measurements, but I did do some response testing even with a ****ed up cone. The off-axis response is quite decent, but there is a big peak right around 500hz where it's just far too boomy (not much at all, but since it's smooth as silk everywhere else, it's noticeable when compared to the same system). I haven't the faintest idea what is causing it, although I do suspect the x-over. I'm seriously contemplating re-doing the x-over circuit and attenuating the mids 4 dB along with the tweeter's L-pad which is already in place. I'm hoping I can knock down the response peak that way, plus, the x-overs I have in there are shittily made as you have seen.