Wall connection clairification

I have read all the threads I could find reguarding this and didn't really find a difinative answer. I welcome any input but I am aiming this question mainly at Rod since you seem to have the most real world experience in this area. I'm about to begin the build out on a new studio located in a warehouse with ajoining neighbors. I'm doing a basic box within a box. I am not able to tear out the existing walls sheetrock on the inside, so I'm forced to do a 3 leaf setup. The new wall spaced in an extra inch will be 12' high and about 40' long. It will have 3 layers of 5/8" rock, GG, and of course loaded with rockwool, and will be attached to the existing wall with rubber straps to avoid any mechanical xmission. To this wall will have the studio's inner walls attached to it. Of course the same on the both sides. My question is will covering the new inner wall and rocking it with the 3 layers first leave me with a higher STC than adding the interior wall frames and stagering the rock? I've attached a crude diagram to show the two methods (of course caulking and all will be done, just not shown in the diagram. I'm grateful for any & all input. Thanx in advance - John

Choice # 2, zig zag is the way to go. See this link from the stickies by Knightfly: The pic shows ceiling to wall corners but I'm sure this apllies to wall corners too. How to drywall and caulk? Step Sequence.... Marc

Loaded with rockwool? That won't really do anything for isolation ya know... that's more for bass trapping and acoustical treatment inside a room. Take the money you were going to put towards "tons of rockwool" and put it into building more mass onto the wall. Although, I have to ask, why three layers of drywall? If you use resilient channel you'd only need two layers of drywall, and the isolation would be better. That sounds like a HUGE space. I'm fricken jealous!!! 40 foot wall? Oh man. haha. That's nice.