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[Steve Crump]

You can't just throw any speaker in an existing enclosure, and expect it to sound good and/or stay in one piece. I strongly suggest you do some more research. Thiele-Small parameters are quite important. Find some modelling software.

Yeah, I am not entering into doing this without some research first. Not only reviewing the info put out by the manufacture, but also asking the manufacture for their input.

But at this point, I may have to re-think the B&C drivers I want to use. I can't seem to find them listed online in the US and Parts-Express said it is a no-go on ordering from them. Heck, I can't even find stock on the B&C XO-4 crossover in the US. That may be my next post on PSW.

Oh yeah, I emailed the US rep and received no response.

[Stephen Kirby]

On the crossover, I contacted Bennett Prescott and he said that Parts Express can get the crossovers but it is a special order.  I did talk to someone at PE to confirm they could do this but abandoned DIY micro wedges as that crossover couldn't keep up with a well done FIR active implementation.  Easier to buy something.  Bennett has FIR parameters for most of their coax's but the cost of a DSP plate amp exceeds buying something like a Yamaha DXR by a factor to make the project not worth it.

[Steve Crump]

On the crossover, I contacted Bennett Prescott and he said that Parts Express can get the crossovers but it is a special order.  I did talk to someone at PE to confirm they could do this but abandoned DIY micro wedges as that crossover couldn't keep up with a well done FIR active implementation.  Easier to buy something.  Bennett has FIR parameters for most of their coax's but the cost of a DSP plate amp exceeds buying something like a Yamaha DXR by a factor to make the project not worth it.

The amusing part is that if I could have found stock, the drivers and crossover would be at my shop or on the way and I would have been forced to work on this project. But, since I couldn't find the items I wanted setting on a shelf, my desire to take on another project is fading.
At this point I am going to search out some other driver options and find out more about what my options are to purchase passive crossovers. Once I find a combination that might work out, I may still pursue at least a trial run of a couple units, but I am in no hurry...

[drew gandy]

The amusing part is that if I could have found stock, the drivers and crossover would be at my shop or on the way and I would have been forced to work on this project. But, since I couldn't find the items I wanted setting on a shelf, my desire to take on another project is fading.
At this point I am going to search out some other driver options and find out more about what my options are to purchase passive crossovers. Once I find a combination that might work out, I may still pursue at least a trial run of a couple units, but I am in no hurry...

Three thoughts if you're still considering this:
A)  If you want to drop a coax driver into a box that is now a separate woof-N-Horn box, make sure you look at the depth.  Most coax drivers are quite a bit deeper than an old fashioned regular woofer.  Also, you'll probably need to either leave the old horn in place so you don't throw the tuning way high or you'll have to fashion a plate to cover where the horn would have been. 
B)  As a previous poster said, T/S parameters matter.  But I'll temper that with the idea that a wedge box is not going to matter quite as much as sub or full range main type of box.  You'll probably be high passing it pretty high anyway.  That said, there are lots of free T/S modeling programs so it's not hard to get an idea of what kind of low end response you'll get.  A passive crossover is at least an order of magnitude more "difficult" to work out than the low frequency tuning.  I would suggest finding a model that has either B&C provided crossover design or a good DIY crossover that has been proven.  BTW, making a passive crossover from a schematic doesn't have to be difficult.  Most use only a handful of components.  Of course, B&C don't provide crossover designs for all their coax models. 
C)  I took a closer look at the 12CXN88 recently thinking it was a newer and perhaps better version of the venerable 12CXN76.  I suggest you look at the nice polar maps that B&C provide.  It appears that the 88 is not a 'constant directivity' design like the 76 is.  This sours my interest in the driver but someone else may not see it the same way. 

[Stephen Kirby]

When I looked at the schematic for that crossover, I didn't see any attempt at phase compensation.  I was looking at the 12FCX76 which has the voice coils in the same magnet structure and so the acoustic centers are likely to be more similar than something with a CD screwed onto the back.  But the more I thought about it, the more I realized that I don't have the crossover chops to do that driver justice and the general purpose crossover wouldn't do it justice either.
Maybe someday PE will come out with a lower cost multi-amp DSP plate for hobbyists and I can "hobby around".  If I end up liking the sound, then I can get into better amps and make a few.

[ProSoundWeb Community]