I live in an 80 year old house with finished basement apartment. We would like to improve the soundproofing for future renters. The ceiling already has the electrical and drywall done. What is the most effective method for soundproofing the ceiling without lowering the ceiling height? We have been looking into mass loaded vinyl in combination with soundproofing insulation. We are open to removing the existing drywall/electrical and then putting it back up when the insulation is completed.