John Sayers' Recording Studio Design Forum Archive

If I understand this correctly, you need to create these 2 rooms independent of each other. Now, if you have double doors leading from control to live, you need one door mounted on each room.

wouldn't that compromise isolation to the outside world?

ideally would sepparate entrances be better (impossible in my case)?

T

Here's a concept drawing to illustrate the basics - ideally, you'd use 12-foot thick concrete for mass, no windows, no doors, no HVAC, no cracks, etc - reality dictates some compromises, however... Steve

That drawing sorta restates my original question...


Wouldn't it be better to sacrifice isolation between control/live rooms (by sharing a floor) and make the seal to the outside world stronger?

Is there something I'm missing?

That drawing gives you a mass-air-mass barrier between either room and the outside world, and also from room to room - that's as good as it gets with a given material and spacing - using separate floors won't compromise anything to the outside - it will only cut down on flanking between rooms, caused by having a common floor instead of individually floated floors... Steve

Your posts are unclear on whether you are referring the amount of isolation required between the control room and studio room or the those two rooms and the outside.

With regards to the first case above, (the late great) Malcolm Chisholm wrote in one of his articles that what is needed is 40 dB noise reduction. How you achieve that is dependent on your budget, accessibility, and of course architectural ingenuity.

With regards to inside/outside isolation, this is dependent on your desired noise floor and outside sound levels. Again the same variables in achieving that goal.

When you start to analyze various options, you start to get into reality trade offs. Would you rather have a ten foot long corridor for sound isolation, or that area used for a recording area? would you accept having to walk 50 feet through twisting corridors and four doors, or would you design a space as a sound lock/iso booth for the in your case rare occasions that you may use it as an iso booth?

The practicality of construction and noise isolation is such that at lower noise levels (in the isolated space) becomes expensive, not because of the incremental cost of the walls, but because of the self-noise of the HVAC system.

Think about the last paragraph. Assuming a structure (we are talking in the abstract here), a 12" concrete block wall is not much more than a 4" concrete block wall, but the improvement in the low end TL is significantly greater thann the STC change would suggest. So we build walls with TLs above 40 dB across the band. What do we do? We put holes in it to get in and out and connect low frequency sound generators (ventilation system fans) to it!

Hope this helps.