Feasibility of Isolating Studio Above Attached Garage

[gullfo]

the blue wall side - deeper batts space once you slide over the green wall towards the ERV, then open it like a closet. simply leaving it as a closed space won't really do much once you're past 12" of air anyways without a bunch of other things happening.

[Elusive Sounds]

Ok let me see if I got this right. So you are suggestion moving the inner baffle box to inside the airspace between the blue and green walls like this, yes?

Then build a new soffit here where the flexible ducts enter the isolated space here, yes?

Then fill the space around the duct, in the soffit, with FG Batts for bass trapping, yes?

In addition to that, build out a "closet" space which is inside the isolated space, inside the blue wall like this, yes?

Then this closet space would be filled with fluffy pink FG, for more LF trapping?

[gullfo]

maybe i mis-understood - i thought the blue and green were the top plate of the walls, not the soffits. it looks like you have the green top plate for the wall and another for the soffit if you're actually only talking about a given soffit space separating the two silencers units, then i'd just leave it as-is for the isolated room silencer and put the green soffit segment back over the soffit wall. technically you don't need the ERV room silencer since that room will be noisy from the ERV and with proper vertical straight walls, easier to add more mass.

[Elusive Sounds]

Let me start over and try to clarify my questions with better drawings. This is a top view of my initial plan:

My first question was if I enlarged the space between the green and blue walls where the white line is in the above drawing, would the larger air gap act as a bass trap? This modification to that wall would only be done above the mezzanine, by moving the green wall out towards the ERV. Here are more detailed drawings of how I'd build that:

So by moving the green wall (above the mezzanine) out towards the ERV, all I've done is create a larger air gap between the blue inner wall and green outer wall. I have not really created a soffit here, unless my understanding of the term soffit is wrong ?...

The mass of the outer leaf (which now includes the ceiling of the existing construction below the mezzanine) would be consistent, in this case new 2x 5/8 DW over existing 1/2 DW for the wall below the mezzanine and the existing ceiling below the mezz, and new 2x 5/8 DW over new 3/4 PW where the wall has been moved outwards above the mezzanine.

So in this scenario I now have locations A, B and C in which I can place my inner and outer baffles:

My first thought was to leave the baffles in A and C and completely fill B with pink FG for bass trapping, but I think you suggested that filling B with FG would not give me that benefit, and could cause other unspecified problems, do I understand that right?

I think you also suggested moving the inner baffle to location B, and then constructing a new soffit in location A, then fill this new soffit with FG and that would be the best way to add bass trapping:

Is the soffit in position A what you were refering to as the "closet space"?