Building a studio from scratch - need input

Hi, I'm looking at building a studio in my back yard and I would appreciate any ideas etc you guys can give me. Basically I have a shed that sits on an approximately 12m square slab. Unfortunately that shed sits about 1m off the fence on 2 sides. Because I have a 1/4acre block I am looking at extending the existing slab diagonally into the centre of the yard so as to further increase separation the studio running drums at 2am and the neighbours etc for noise levels. With the slab extension I would like to cut the existing concrete to give me a flat edge on one corner and to help isolate between the two rooms. The control room will be built on the majority of the existing slab and the live room will be on the extension. The external walls will be besa brick, and the interior will be two physically separate rooms. I'm not sure how to deal with the roof yet, I could salvage a large amount of tin from the shed but I'm not too keen as it will get real noisy when it rains etc and probably won’t help contain too much noise. I would appreciate any layout tips you could give me and where to place absorbers and the like. My plan is to build the roof at least 4m high in the studio and I’m not sure how high I need in the control room. Here is a quick design I did, it's rough with no dimensions etc but I'll add those later (I'm at work right now and don't have the measurements). Thanks for your help :) Tony Peaker Bag O Bonez Recording