Thanks Wayne:We miss you at audio asylum!! Too bad for the cat and mouse games played over there at times. Remarkable results with these VC heat dissipating plates. Looks like I will not have another pro use (or even home) speaker without them. Apparently not worth having vents going outside of rear space (with the possible driver parameter changes) since most VC damage is a local heat phenomenom. Large Aluminum plate will also help dissipate rear space heat anyway.
From my days as DIY plummer I remember not to contact Cupper tubing with other metals since it leads to a chemical reaction. Therefore the use of cupper clamps to hold cupper tubing in place. Will look into this further to be sure since seems cupper tubing is ideal for wicking away VC heat out to a lightweight aluminum plate for dissipation. But likely the cupper would chemically react with the iron in the pole piece even with thermal paste in between.
Can see a big advantage in using these heat dissipating techniques not only on pro use speakers but also in high resolution dynamic low power drivers with edgewound aluminum cupper clad VC wound on cardboard etc formers. Like old Altec and JBLs.
Anyway thanks Wayne for all the free education and info and congrats on your fine speakers.
Nicolas