It is a cement floor with an 8lb carpet pad and carpet. At 6 to 8 inches of cement, I live in Florida and the complex was built in 2006. I have no other noise issues, just through the floor.
6" to 8" of poured concrete, "cement floor". You assume the sound from your audio system is through the floor. 6" to 8" of poured concrete? You must be listeng to your audio system pretty loud. Using speaker spikes?
I would say the building is not a 3 or 4 story building. Just a guess it’s may be 10 stories. Maybe a lot taller than that. Interior walls for each story are built on the concrete floor slab. Hard to tell how the exterior wall are constructed. Depends on the construction of the exterior wall of the building. Sometimes the exterior finished walls of the interior living space of the building is metal stud with drywall. Drywall thickness??? I have no idea what building fire codes are in Florida. Floor to floor fire break code, fire stop penetrations, hour rating requirements. ??? It can depend on how old the building is. You said the building was built in 2006. Are the Condo units in the building fire sprinkled? Makes a difference on floor to floor fire stop ratings Thus possible sound transfer between floors. If you knock on the exterior wall is solid like concrete or sound like drywall. Thick drywall?
Is your audio system speakers on an exterior wall?
Vertical mechanical pipe chases?
Before you start just throwing money at the problem I would first try talking to someone in building maintenance. Not cleaning personnel. Mechanical maintenance personnel. They may have access to the building construction Blue Prints.
You didn’t say what your cooling/heating system is. Therein is it common building system.
Individual exhaust systems? Bathrooms and kitchen range hood exhaust? Each Condo space has a separate vent to the outside of the building or ties into a building central duct system?
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