I looking to add some speakers to my basement ceiling for rear surrounds and two additional speakers above the breakfast bar. Is there something I should put on top of the speakers to help 'contain' the sound and prevent it from going into the main floor? Someone told me to just get some plastic containers and put them on top of the speakers. Someone else told me that there were these sound absorbent rubbery pockets that help to reduce the sound from traveling up to the main floor. Sorry if I'm not making it too clear. I want to prevent sound from traveling from the speakers to the main floor and was looking for suggestions. Thanks.