Kind of a two edge problem since the integrity of their ceiling can substantially affect the outcome... Had good luck with a suspended drywall ceiling and the blue jean batting - but that was from the ground floor looking up. The goal was isolate the downstairs guest room from my partners wood floored home office directly above their heads.
Given the probable cost and complexity I am going to offer some obvious advice - call an acoustician or at least a contractor who specializes in home theater or recording studio installations. Get very specific about how many db of attenuation various approaches will actually achieve. And make achieving those specifications part of the contract if you can.
There are some effective ways of decoupling the speakers from the floor - this eliminates a good deal of the vibration that goes through. Checkout some places catering to the semi-pro and pro business like sweetwater dot com and see what they have for acoustic treatments. You could definitely knock the bass down and help matters.
Truth is if you are pounding at 100-110db levels nothing is going to work but building a room within your room.
Given the probable cost and complexity I am going to offer some obvious advice - call an acoustician or at least a contractor who specializes in home theater or recording studio installations. Get very specific about how many db of attenuation various approaches will actually achieve. And make achieving those specifications part of the contract if you can.
There are some effective ways of decoupling the speakers from the floor - this eliminates a good deal of the vibration that goes through. Checkout some places catering to the semi-pro and pro business like sweetwater dot com and see what they have for acoustic treatments. You could definitely knock the bass down and help matters.
Truth is if you are pounding at 100-110db levels nothing is going to work but building a room within your room.