Damping to exitation of parasitic modes of

If you don’t have any Shun Mook Mpingo discs in the system you’re really missing out. You have my sympathy. Even one Mpingo disc in the room, properly placed, will cause your jaw to hit the floor. Your wife will call out from the kitchen, "Honey, what did you do to the system?" Finding that precise location, as fate would have it, is what drives audiophiles to the brink of, well, the brink of something. Of course, resonance control is my middle name and I have many resonance control products, including a rather largish constrained layer damper. The specific material I use for the viscoelastic layer is, however, proprietary. If I told you I’d have to kill you. 😬

Speaking of vibration and damping has anyone tried damping the dust cap on the woofers of speakers. Well, first I should ask has anyone run a test tone through the speakers at around 200 Hz or so to hear just much much those bullies distort and ring?

I've found using differing materials in cascading layers "For different Freqs" I start at about 10k and work down. It more easily defines problem area's by isolating migratory vibration but there are still area's of regeneration. I think fields are interacting and may be performing as a type of wave generator. Juries still out on that one. Coincidental entrapment seems to work very well though. You simply have to make the law of averages work for you by trimming the variables with the cascading layers actively as well as passively damping plus transduction "several types". To the point where the deck is basically stacked in your favor.     Have you ever tryed introducing disruptive pulse voltages at very low freqs'?  This seems to help with sensing also below 6 htz.

"Sympathetic Vibration" just means that one vibrating object is driving another

driven or forced damped harmonic oscillator is the best search term to get the right differential equations...

I agree that you will likely need different materials for different freq. bands.