I have good tube gear at home on my Be20s, but I immediately recognized the (slightly ;) trashy confused sound at high volume of my stock speakers when I heard the stock Be10 at RMAF. All that evaporated with the modded pair even with the SS electronics, so I'm sure it is the upgrade responsible for the big improvement.
According to drunken rumors overheard at RMAF the Exemplar crossover upgrade with be available from Usher early 2009 and estimated to cost about $6000, including new internal wiring by JPS. The high cost is due to very good quality parts, but I don't know brand details. The Exemplar exhibitor (forget his name) explained to me that some minor changes to the crossover circuit are made, minor cap values, etc, so it is not strictly a pure parts swap mod. But I believe crossover frequencies are retained. It is Joseph D'Appolito designed crossover. I like the sound better than the Be-718 which has tweet crossover at only half the freq of Be10/20.
I am looking into making my own replacement outboard crossovers using Duelund parts and JPS internal wiring. External crossover will allow experimenting with active crossovers / tri-amp in the future. I have had the speakers apart before, it is not too bad if you're careful. And yes the stock wiring looks like a lamp cord from your grandmothers attic, thick clear vinyl insulation with thin dark stranded copper inside. You need a very small socket (~1/8"??) driver to remove the special bolts holding on the woofers, and an allen wrench for upper drivers and rear panel. When reattaching, do not tighten to hard, the threads are metal inserts in MDF so there is a torque limit! You need a staple gun with 1/2" - 5/8" long staples to reattach internal cotton bat (crossovers are hidden behind this.) The wires to upper drivers pass through a small hole filled with thick tar putty, can be reused, but messy. I accessed the crossovers through the bass driver holes easily with plenty of room inside to access crossover attachment screws. Patience is needed to reattach them.
Thanks for the tips and advice Serus.
Nice review Tboooe
Rich