Brick wall for room-in-a-room construction

Hi, I'm still calculating the cost of my soon-to-be studio, which is going to be double wall construction, which the existing walls are brick walls. First, I'm going to use the usual recommended gypsum board on wood frames, with insulation inside the frame. But when I compared the construction cost here in Indonesia, I found that cement-plastered brick wall construction is far more cheaper than the gypsum board on frames with rockwool insulation. But the question is, which is better for soundproofing? Why nobody recommended the brick wall over the gypsum/frame/rockwool for the studio construction? Ari

Why nobody recommended the brick wall over the gypsum/frame/rockwool for the studio construction?

I suppose it's because everywhere, except Indonesia, it's more expensive ;) You won't be saving the rockwool because you will probably need it in your cavity between the brick walls anyway and I'd assume that's your major cost?? cheers john

Well, yes. :( A piece of Rockwool slab only, which is 1,2 x 0,6 m in size, frames and gypsum board not included, is twice the construction of 1 m^2 brick wall here. What if I just let the cavity between both brick wall empty? Ari

Check this link out Ari - http://www.australbrick.com.au/techinfo/stc50.htm maybe you only need a single brick wall ;) cheers john

Thanks John. I really appreciated it. Another question, since I can control the volume of the speakers, but not the acoustic drums, what STC rate do you think is the minimum STC for the studio/drum room? I'm thinking of using single brick wall for the control room, and double brick wall for the studio/drum room, if neccesary. Ari