Quote Originally Posted by VolvoHeretic View Post
GM, it has taken days for what you have said to sink in. Sorry, I'm dense. I guess I want to solve for added weight with an arbitrary Fb? ?And hope that I don't overload with watts, but maybe the good thing is these woofers are rated up to 150 wpc? Sorry for the ignorance, but I?m and ignoramus, I am just now, after 35 years, trying to figure out this audio stuff. I will see my son, the engineer tomorrow and sick these formulas on him, and see if he was paying attention in Calculus class.
Correct and just like with any speaker alignment, you don?t want to over drive it into damaging excursion, which the lower it?s tuned, the lower in SPL this will occur.

Then there?s the issue of how much added mass referenced to the driver?s moving mass [Mms] the suspension can safely handle, which only the manufacturer will probably know, but FWIW I?ve loaded down drivers up to 4x Mms [mr = 4] which cuts Fs in half and doubles Qts, though power handling is severely compromised unless it has a lot of Xmax, which prosound drivers typically don?t have, especially MI drivers such as the 418, 421.

Really, except for turning a burned out driver into a passive radiator [PR, AKA drone cone], I only recall adding mass to raise Qts.

No need to apologize, unless you?re a math/physics wiz, you don?t pick this type of info up real quick; for sure I didn?t. Oh well, better late than never, right?

Actually, I think it?s just high school Algebra, but I failed it, so not sure. I had to learn this stuff experimentally and it was only much later I was given the ?long hand? math and even then had to have yet someone else program it into Lotus 123 originally and later into MS Excel.

GM