I have a set I have been enjoying in ported boxes, playing down to about 45hz. Hopefully will have a set installed in some kick panels in the near future.
To answer your question about the midbass, IMO these fall right in the middle. They are not absolute midbass monsters, but are not weak either. That’s running them side-by-side next to quite a few other 6 1/2 I have laying around. The modeling program says about the same.
What makes them or any good speaker better than average. It’s all in the motor design. That’s where the magic happens. The rest is just parts.
As stated above these were designed for a special niche. I think where they really shine is they cover a broad spectrum of that niche. They are VERY flexible. They’re just as at home in an SPL rig with the sub covering a little more ground, as they are in an SQ vehicle with the gains dialed back and the crossovers set lower. Same goes for the top end. they have decent reach that could be used to your advantage in an SPL vehicle to save the tweeters.
Why the Evil’s? Anyone that knows Aaron and Mark knows their heart and souls go into their products. They would rather make one good product that they are pleased to hand to their friends, then have a slew of mediocre models just to make a profit. The Evil’s are a premium driver, at a working man’s price. These guys take care of people. That’s why.
Beyond that simple physics apply. A speaker with a heavier cone should have better midbass, IF the motor design can maintain motor force throughout the majority of the cones travel. That and sound displacement....Surface area x Xmas. Surface area and the weight of that larger cone being what you are lacking.
If you have any tuning capability you should be able to at least get what you have sounding good. You won’t have the midbass output of a 6 1/2, but you should be able to get things to sound right.