Thanks for reply Stuart!
Ohh, now everyone can read where I live. My studio is going to be located in my basement of my house. Two small rooms. 15.5/18kvm.
So, by angling your glass like that you get LESS isolation, and you do not actually solve the problem that everyone thinks you solve!
How can i have less isolation if I have a larger distance between the glass? I have widened the wall to the top of the window. I can understand your point if i have not done so.
Regarding the angle and possible reflection of the microphone according to your picture, I always put the singer so that his or her nose points against a corner in a studio when I record.
One of the two walls, that the double wall is going to be built of, also has an angle so that the distances between them become larger and larger. Yes, you're right, it's easy to make mistakes when you set up a microphone for a recordning situation, but there is time to learn the room in the future
Regarding having, as you wrote, "cloth (fabric) across that gap, to make it look neat and hide the insulation on the other side." i wonder if nature latex(don't know the ageing aspect of this material but I think its a harmful material to humans), that is flexible to hundreds of percent could seal the gap, ever air sealed? I will have two doors in the wall to and i don´t want to seal the joint air tight. I have people around me that I do not want to expose to the small particles in the insulation that are inside the wall.
Best Regards