> If the danger of too much stiffness in the treble is as you describe, why > the fish? Doesn't that increase stiffness and reduce mass? > > David Love It's not all that much of a danger, because it doesn't happen often. I typically mass load the treble bridge to extend sustain a bit, not to compensate for over stiffness of the board. The fish, like the bass cutoff, is to shape and size the diaphragm to more nearly accommodate the frequency response requirements, and minimize spurious resonances. It's to give me more control of the result than just accepting what the original rim shape gave me. Even though I use a lot of ribs, they're smaller than the originals, and sized by intent for what I think I want in assembly stiffness. The idea is to control stiffness throughout the scale according to a conscious plan, rather than just making everything arbitrarily stiff. Why do people put lacquer in hammers to harden them, then needle them to soften? They're not looking for hard or soft, but some semblance of control. Ron N
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