[samplesj]

I'm really really happy with my 2 channel system right now, but I know when I added room treatments to my HT system I was amazed at the improvements.

I know what I want to do with first reflection points and bass trapping since I have a local vendor that carries 703, but it seems like most planar speaker users use diffusion instead of absoption behind the speaker to help keep the dipole's spacious sound.  Based on most users suggestions I'm looking for around 4' wide x 6' high behind each speaker (48sq ft total ).

I had been planning on building a skyline clone based on the recipe I found http://www.pmerecords.com/Diffusor.cfm'>here.  However I just don't have time.

While real Skylines do fit within the budget, it wouldn't leave much left over for new music for a while .  As a potential alternative I thought about using Auralex T'fusors (5.5" depth, but not QRD or prime residue based).  However a vendor I spoke with is suggesting that from the Auralex diffusors Q'fusors are actually better for my given purpose.  I see that the Q'fusors are QRD based which means there is some reason to expect good results, but they are under 3" deep and I've seen a lot of bad comments about shallow diffusors.  Once I saw how shallow the Q'fusors were I called back to order some Skylines, but this same vendor said that they had actually stopped using Skylines because the Q'fusors were much better.  They do also still sell the Skylines and they do cost more so I don't really suspect it was steering a sale just for profit, but who knows for sure.

Among the RPG products I could also swing enough HemiFusors or maybe OmniFusors in my budget.  Unfortunately the QRD 734 is too expensive to cover the full area I want to and stuff like the diffractal are way over my budget for that much coverage.

I've looked at the Art diffusors, but they seem to be pretty much the same pricing as RPG.

While I don't have time for the skyline clones, I could easily build some poly diffusors, but I'm not sure I'm far enough away (~10') for them to sound right.

Any other suggestions or recommendations?

[bpape]

If you're intent on buying a pre-finished solution, I'd look at the Auralex Mini-Fusors.  They're reasonably priced, can be set in arrays to work in 2D, and can be filled with 703/705 in the rear to provide a small amount of bass only control.

I personally might consider making a polycylindrical diffusor and mounting it vertically behind the speakers.  Everyone just assumes it has to be horizontal - but it doesn't.  This will allow diffusion deeper down into the bottom, provide better polar plots if implemented correctly than a QRD, give you some nice height extension that most panels can use, and can be done VERY reasonably.

Just a thought.

Bryan

[ctviggen]

Here's one article on how to make such diffusors:

http://www.jaytorborg.com/diffusors.htm

[samplesj]

Well, as I said above I could easily build some polys.  They'd even be cheap compared to the other stuff.  For some reason I was thinking that polys had a minimum distance required for better results.  I went back and looked through the Handbook and it doesn't appear to be true for them.  Not sure where I picked up that idea.

I don't mind small/midsized DIY projects at all.  The killer with DIY on the skyline clones was the massive amount of time because of how many I needed.  The skyline clone site gave an estimate of 2-2.5 hours each and I was looking at 24.

Just to make sure I understand the concept the link that ctviggen provided isn't a true polycylndrical diffusor because it is a half circle so it doesn't provide variable arcs.

There are a couple of threads on polys over at AVS between Bryan, Ethan and Terry Montlick.  In one of those Terry gave out a 30% rule so I should be able to calculate the right spacer in the middle using that.

edit: fixing spelling of Bryan's name