Need Advice On Placing Absorption Panel On Ceiling

I plan to experiment by placing 2 pieces of 2" thick absorption wedge panels on the ceiling. I would be grateful if anyone could advise beforehand on the recommended arrangement of the panels. This is what I have in mind :-

Arrangement Sketch

If some diffusion is required at later stage, I will add thin long strips of wood in between the wedge as proposed by Ethan Winer.

Any advice would be most appreciated.
I put some 4'x4'x2" sonex on my ceiling.They are 12',I couldnt hear a difference so I dont know what to say about your room.Not many people put acoustic foam on ceilings though many do their walls.For the obvious reason.I would stay away from that project.If you must,be sure to get lots of 3M 77&78 adhesive spray and use panels no bigger than 2'x4'x2".Stay away from the 4 footers,there hard to handle,good luck,Bob
Thanks for the response Bob. Your experience of being not able to perceive any sonic differences has pretty much reduced my level of enthusiasm in going ahead with the project that could possibly ruin the ceiling after that (in an event I don't hear a difference and need to dismantle those panels). Will see if I can find something to prop those panels temporarily, just to be sure if they are able to bring some benefits before I permanently fix them to the ceiling.

see my system photos...ever evolving category, welcome to the pond
i have 4 echobuster panels on the ceiling. they (each) are about the size of a door- i.e. 3.5 ft by 6.5 ft. and spaced apart by about a foot. they are held by 4 anchor bolts and 4-L brackets. the brackets were screwed into the ceiling 1st. then the panels were held up by TWO PEOPLE ON TWO LADDERS, and then screwed through the descending piece of the L-bracket into the edges of the panels once
they were measured to be parallel to one another. the panels don't weigh much at all. but you have to clear the space underneath- a pain in the "neck". falling popcorn will get all over the stereo unless it is completely covered. in my case the ceiling is really high, so
the TWO INSTALLERS must be comfortable working on two 8 foot ladders, and have to take PRECISE MEASUREMENTS.
as for the sonic results, they were well worth the effort- slap echo was significantly reduced. plus i acheived the "concert hall acoustic ceiling" appearance that i was hoping for. as i recall, the four custom-made panels cost about $1200 shipped, and they included the hardware too. my "theory" that adding sound-absorbing surfaces to the room REGARDLESS of the precise location would STILL be helpful, and luckily it worked. my walls already had framed-art that i really loved, so i was determined to leave them in place. anyhow, the room looks nice and sounds nice. YMMV of course.
Thanks for all responses. I will most likely give it a go.

French_fries, may I know if your Echobuster panels are purely absorption, or a mix of absorption and diffusion?

Thanks in advance.
I found that RotoFast connector/mounts made all mountings quick and secure, even on the ceiling.

Interesting post Frenchfries.I commend your ambition and attention to detail.Glad to hear it was a success.Thats the right way to do the job.I set-up a Bakers scaffold which helped immeasureably[sp],but I am glad if I dont have to work on the ceiling again though some rooms require it for optimum sound,cheers,Bob
I have a series of RPG absorber/diffusor panels on the ceiling. I found them to be very effective. Before I put them up, I had constant problems with edginess. Placing absorbers on the sidewalls at the reflection points did not do enough.The ceiling turned out to be the problem. You can see a photo of my room on my system page.
Beautiful!Yes,8' ceilings with those speakers would seem to be bouncing off sound fearsomely.Pressurized,I guess would be the word.....I would love to hear your system,I am very impressed with your style,cheers,Bob
I simply bought 2" thick Owens Corning 703 panels (2'x4'), made 2'x6' wooden frames with 1x2, stuffed 6' worth of panel in each frame, shot nails thru the frames to hold the panels in place, covered the panels with fabric, and hung them from the ceiling using eye bolts and metal tackle from the hardware store. Worked great, reduced slap echo alot, looks good (similar color as ceiling), cost less than $100 for the whole shebang! You just need to find a source of 703, and I think the minimum you can buy is a box of 6. Good luck, Peter
MR. RYDER, they are purely absorption panels, kind of brownish-beige. getting them lined up properly takes some effort, but they're IMHO quite attractive. i even added a 5th panel over the front doors to the house, which makes up my "rear wall". contact echobusters and they can pull the order and give you further information. ps- if you purchase from them be specific about EXACTLY what hardware you're planning to use to put them up...