Sealed boxes (QTC of .707 = flat response, lower QTC = more low end, higher = less), and I'm not sure if they're all D4 ohm. Minimum & maximum recommended air-space or QTC of .707.

Fi Q 12
1.5cf3
QTC = .4776
FC = 44.15 hz
F3 = 73.18 hz

Audiopulse Axis 12 2500W
.6cf3 = 47.37 hz
1.4cf3 = 36.31 hz

RE XXX 12 2000W
1.267cf3 = Q .707 / 36.75 hz

Soundsplinter RL-S 12 - SPL 80.5db - 2000W
2cf3 = 37.78 hz
2.5cf3 = 36.52 hz - optimal
3cf3 = 35.66 hz

SSA XCON 12 1750W
.9cf3 = 49.91 hz
1.5cf3 = 43.76 hz

SSA Icon 12 1000W
1cf3 = 47.68 hz
1.35cf3 = 43.77 hz

Soundsplinter RL-P 12D4 1000W
1.35cf3 = 41 hz

JL W7 1000W
1cf3 = 49.64 hz
1.5cf3 = 43.46 hz
2cf3 = 40 hz

Image Dynamics IDMAX 12D4 1000W
1.5 cf3 = 44.15 hz
Graph http://www.*********************/man...DMax12D4V3.pdf

Image Dynamics IDQ 12 500W
1.3725cf3 = 46.75 hz (Q .707)
Graph http://www.*********************/man...20D4%20V.3.pdf

SSA Dcon 12 300W
.9cf3 = 58.67 hz
1.2cf3 = 52.71 hz

 

Awesome stuff guys... well I know what I'm doing now. I appreciate all your help

 

T212D4 you wont be disappointed.

 

m5a ixl good value