Surface area vs. volume for soffit-style traps . . . a small room question
I'm considering making some soffit-style bass traps for my smallish apartment, but wanted to get some thoughts on the effectiveness of the idea. I've been reading through a lot of these threads lately, and it really blows my mind to see all the info that's being tossed around on this forum.
A bit about my room:
11'11"Lx9'9"Wx7'10"H. As expected, a lot of low end <120Hz junk. I currently have four GIK 244 2'x4'x4" bass panels, one each straddling two front corners and two suspended above my head, 4" off the ceiling. (This was the placement suggested by Brian from GIK.)
Due to various pipes/shelving/doors, and also the renter's status, I'm having trouble finding places to put more panels. However, there are a couple of corners where I could probably get away with stuffing a few soffit-style traps. My question to you folks is, would a 14"x14"x48" trap--in a rear floor/wall/wall corner--do any real good in low-end land? At its widest point, it would be almost 20" thick . . . surely that would be worthwhile?
Also, for this size, what type of material would I want? I've seen people say that sometimes the 'fluffy stuff' is actually better for LF absorption than rigid fiberglass, but I haven't been able to determine what factors go into this determination.
Thanks in advance for all your help!
Living the dream . . .