Bonnie tentatively is recommending that the 4’ deep, straight soffit and the shallower angled soffit be filled with blue jeans insulation and be covered only by fabric. She seems to think the assumetry is okay, and that whatever low frequencies these soffit sections absorb at the 9’ to 14.5’ elevation of the room is all to the good.
Sounds like a good idea just tell your contractor to put the provision in for closing it up later if desired. Should be simple enough to try with it open and covered and see what happens.
Bonnie tentatively is recommending that the 4’ deep, straight soffit and the shallower angled soffit be filled with blue jeans insulation and be covered only by fabric. She seems to think the assumetry is okay, and that whatever low frequencies these soffit sections absorb at the 9’ to 14.5’ elevation of the room is all to the good.
I might consider blocking off the downward/bottom portion of the soffit and only leave the vertical area open, or alternately, and probably preferably, using a perforated panel of some variation, similar to the "scatter plates" GIK uses that are visually very obvious. Many are using similar devices now, and you can choose to either expose the hard scattering surface or even cover it with fabric depending on the look/feel you are after.
Of course the patterns have an impact on acoustic behavior in 3 ways:
The largest span and area of hard surface vs open area, along with the pattern determine the reflective/diffusion characteristics.
The overall open area vs any trapped volume behind the panel (soffit internal volume in this case), which determines the low pass effect and any enhancement of the LF absorption.
The thickness of the material is considered in combination with the open area (#2) and the rear volume to determine how the openings change the effect vs frequency.
You might want to ask Bonnie if she has a pattern/material she might prefer for this use.