Hey Everyone - I'm looking for some feedback and thoughts.

I live in a 2 level apartment house. Me and my roommates live on the upper and 3 other guys live on the lower. My band just started practicing in the basement with permission from the guys downstairs. Its rather muffled up in our place on the upper, but could definitely feel some vibrations. I knocked on the door downstairs to ask if I could get some feel for what they're experiencing as my guitarist and drummer were downstairs jamming. They seemed pretty accommodating, but it was certainly a lot louder since we're practicing literally right under them. Even thought hey said they were cool with it, I'd like to accommodate everyone as much as possible so nobody decides in a few weeks that they can't stand it anymore.

Anyway, the ceiling above us in the basement (the lower's floor) has cavities where we could possibly run insulation through to line it. Also, our lead singer works at a place where she can get a lot of indent foam as well, which we were planning on lining the walls with.

Do you think this would be an effective way to dampen some of the noise and (more importantly imo) remove some of the vibrations? If so, how effective?

Thanks everyone!
Epiphone G-400
Peavey Classic 2x12 Combo
Squier Jazz Bass
The sound is transmitted in two ways.

By making the fabric of the building (mainly the intervening walls and ceilings) vibrate. The main way to reduce this is to add mass, heavy carpets and underlay on the floor above, lining the walls with extra layers of plasterboard etc. Doors are often thin and light so they vibrate easily, put heavy curtains in front of them.

By air transmission. This is much easier and cheaper to fix; seal around doors and windows caulk any gaps in floorboards and check for air leaks where walls floors and ceilings meet. Keep windows and doors closed when playing,

Good luck