kappa 15lf vs kappa 18

thanks again for your help colin. here's my question. looking at the eminence published charts the kappa15lf has a big dip between 30-50hz. the kappa 18's response is smoother with a gradual rise from 30-20hz. also the useable response is 25-500hz for the kappa 18 versus 35-3khz for the kappa 15lf. i'm green at this but to me it looks as if the kappa 18 is the better choice. if i'm missing something help me out please. i'm planning on placing the jbl 4655's on top of the subwoofers and they will be in corners.

on top of all this i just received a sample eminence driver(oem) available at a surplus price. take a look at the spec's and see if this is workable as a sub.

18" subwoofer
accordian cloth surround
3" kapton voice coil-4 layer
95oz ceramic magnet
Re(ohms) 7.84 Fs(hz) 22.74
Le (mh) 1.88 Mms(g) 145.3
Qm 10.30 Cms(mm/N) .3372
Qe .310 Rms(Ns/m) 2.0156
QT .300 Vas (L) 615.56
Xmax(mm) 4.80 Sd (cm^2) 1140.09
BL (Tm) 22.92 EBP 73.40
EFF(%) 2.25 SPL (db) 95.50

let me guess, these 18" drivers need a huge enclosure?

thanks for all your help.

cheers,
george

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