Rib Crowned Hamburgs ?

[Ron Nossaman]

Erwinspiano@aol.com wrote:
>       Del
>     Thanks for the perspective but what a bout an appropriate amount of 
> mass in this area adding to the impedance qualities? I realize the 
> importance of rib stiffness for this purpose but....how much mass is too 
> much or not enough?   Too much thickness in the treble can give a stingy 
> sound  & too thin sometimes a a sound not dark enough for my liking
> 
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>  Also 
> most diaphramized bords are 8 mm or less around the perimeter*

Right. More like 5. So where's the mass there?

Ron N