One of the things I'll be mentioning to Great Plains Audio is applying Aquaplas (
now called
Antivibe) to the tangential surround of the aluminum compression driver diaphragm. JBL applies Aquaplas/Antivibe to the whole diaphragm when you buy a 435Be, but I feel this is a mistake. The part of the diaphragm with the most chaotic radiation is obviously the surround, and it's an area where mass-damping and outright suppression of radiation is desirable. That is NOT true of the diaphragm dome, where low-as-possible mass and uniform emission into the phase plug assembly are primary goals. Raising the mass of the diaphragm is extremely undesirable, since it depresses efficiency and decreases HF extension.
Since the dome of the diaphragm and its surround operate in completely different ways, and in fact have completely different functions, it only makes sense to treat them differently, rather than applying damping goo to the whole thing. Adding a bit of mass damping to the surround seems like a good idea, and is likely to improve the mechanical termination between the moving diaphragm and stationary mounting ring.