Advice on replacing 12 in woofer in Martin Logan Monolith III's


I'm needing to replace the 12 inch woofers in my Martin Logan Monolith III's.  I am running a dBx 260 active crossover so I can control x-over points and output.   Any suggestions? 
stevepa
Yes, the driver ML commissioned Eminence to make is rubbish compared to the rest of the speaker, it has a one note bass, I’ve got all the T/S parameters on it, not good.

The ACI-SV12 ( Meniscus SW1284 ) I matched and replaced them with are miles better, for that box. You’ve got to find a used pair though. I could find much else that suited.

Heavily stuff the box so you get a lower Q (.6) to equal the speed of the esl panels, cross the SV-12’s over with 24db active at 130hz,
Keep using the ML’s own passive 18db xover to the ESL though, as it sound better than active. You’ll then have a speaker that comes close to the ML Neoliths.

Cheers George