small basement room3

I intend to use room entrance corner as a voice booth so i can get more insulation from stairwell to big aerea adding one extra door . The idea of building room in a room start with gluing a 10 cm thick leyer of 60 kg/m3 all around walls and ceiling, 6cm thick 160km/m3 at floor with open cell foam folowed with 1 plaster board glued layer . frst fase. second fase Walls: another layer of PKB2 glued and a final plaster board glued. At ceiling i would angle one side of beam but i gess it wont stand glued maybe i should start with some anging ceiling since i have that 45 cm higth void betwen beams. At the floor second fase would be pkb2 and 2,2 MDF layer and glued wood floor will it be to much since this is the lowest floor?