Sometimes I wonder If I'm talking to myself here but I'm just as guilty as the next for lurking and not posting.....
The Dimensions are 24x17x17. This is the maximum size trap that will fit in the back corner. This size still yields an even number of triangles per 2x4 panel.
I think the 24x24x34" traps are preferred but I've seen 12x12x17 traps used too.....
No I'm not planning to cover the corner trap with reflective covering my room is nowhere close to over absorbed. Its actually already covered with burlap and placed into the theater.
I have given some thought to the over absorbed issue though. If I use any panel traps at or behind the seating area I am going to either do pressure traps like the one you built or velocity traps with reflective coverings like you mentioned or a combination of the two. This should help keep the room lively, especially behind the listener where some stray sound should help. The back wall is an exception to this rule since my room is so small my only hope here is to totally absorb it.
Here's my treatment theory(Comments/Suggestions Welcome):
- Build Soffits and fill with broadband absorption.
- Broadband absorption First Reflection points walls and ceiling.
- Bass Trap all corners possible(superchunks or panel straddles depending on materials avail.)
- Broadband absorption entire back wall
- Broadband absorption entire front wall
- Measure and interpret Waterfall(modal ringing) and ETC(Early reflections).
- Treat high gain early arrival reflections with surgical broadband absorption.
- Severe modal ringing in the 80-500Hz region I would address with tuned pressure traps in high pressure regions.
- Assess how lively the room sounds and address HF over attenuation as needed.
Broadband Absorption = 3.5" Safe-n-sound with 3.5" air gap.
Pressure Traps = Something similar to Ethan Winer's design found here