I was recently asked an interesting question.
Is it better to have the loudspeaker crossover inside or outside the loudspeaker?
At first, the answer seemed rather simple. Inside, of course. Shorter wires, fewer binding posts, etc.
Yet, in thinking about it, I can see at least one advantage to an external box filled with speaker crossover parts (like we did on the IRSV). I would imagine there would be benefits from lowering internal vibrations. When external in their enclosure, the crossover parts are not vibrated by the loudspeaker's output.
We know that anything one can do to dampen or isolate sensitive parts from the speaker's outputs is almost always a benefit.
The problem with any of these ideas is the simple matter of trade-offs. What are you giving up, and what is it you hope to gain?
My guess would be that a slight overall advantage would be gained with an external crossover enclosure. And with that in mind, one would have to ask the second question.
Would it be worth the hassle?
As in any noble experiment, one must always ask the right questions: cost vs. gain and hassle vs. ease of use.
My vote would be to keep your speakers build as the designer intended.