I have a pair of 4343 monitors whose 15" and 10" drivers need refoaming. I figured that I would use this opportunity to upgrade the components to 4344 specs. I've located the a pair of the 2235H drivers and a pair of the 2122H drivers. I've run into a snag though on the 2425J compression driver: First of all I'm not finding any on eBay or when I checked a couple of the local JBL service centers. Secondly, when I called JBL Pro they said the 2425J is NLA and has been replaced by the 2426J. My question is: Is the 2426J sonically comparable to the 2425J? Or should I be patient and keep looking for a pair of the 2425J.

My next dilemna involves the crossover. The 3144 crossover specified for the 4344 monitor also appears to be unobtainable or at least very rare. How much different is the 3144 crossover vs the 3143? Can I get by without changing it? I will be bi-amping the speakers and using an electronic crossover so I really only need to address the difference as pertains to the crossover section for three upper drivers. Or is there a different crossover solution that I haven't but should be considering. And are there other upgrades that I'm overlooking.

Any recommendations you all can provide will be greatly appreciated. Thanks.