Some progress here,
If some of you don't need and all bells all tit bits active crossover but more a simple very hight quality 2 way box with provision for 12/18 db slopes or JBL monitor xover options options here is an idea.
I have been looking at a very simple but high quality buffer stages using Dual JFets in a differential / source follower design offering very low noise and distortion with low impediance drive capacility.
The simplicity is such it could be arranged on vero board with provison for fitting the RC values for the filters.
Over the Xmas break I will try and breadboard the design and test it and report on the subjective performance.
I will then consider offering the unit in the form of a black box to interested forum members.
Ian