[medium jim]

If I ever get the ambition....

http://www.youtube.com/watch?v=qFeM2uWuMZI

Jim

[Rclark]

From what I understand, the ideal diffuser type for Maggies is the QRD type that spreads horzontally, not both horizontal and vertical. To 500hz is fine, the eventual Dual Core and some bass traps will take care of below that. The Maggies don't load the room very hard, at least compared to anything else I've ever used, there's lots of bass, but the room doesn't bloat up like it always had before.

[medium jim]

From what I understand, the ideal diffuser type for Maggies is the QRD type that spreads horzontally, not both horizontal and vertical. To 500hz is fine, the eventual Dual Core and some bass traps will take care of below that. The Maggies don't load the room very hard, at least compared to anything else I've ever used, there's lots of bass, but the room doesn't bloat up like it always had before.

Not according to Josh358 who advised me to go with both horizontal and vertical diffusion.

Jim

[jk@home]

Always thought your listening space looked awesome. Yeah, that's about what I have pictured as far as the diffuser. I think I want to build 3 seperate panels and mess with them, place them all together, space them out, try all sorts of configurations.

Another thing you can try is placing an absorber/bass trap panel dead center on the front wall, between the diffusers which would be placed at the mirror points described above. Lots of folks on the MUG recommend this and of all the bass traps and absorbers I have placed so far in my room, the center absorber seemed to make a big improvement with my MMG's sound.

[Nyal Mellor]

Not according to Josh358 who advised me to go with both horizontal and vertical diffusion.

Jim

I'd try and keep the sound energy in the horizontal plane rather than sending it towards the ceiling and the floor. Psychoacoustically I feel that is better because it gives you more sound energy arriving from lateral angles which improves perceived soundstage spaciousness. The exception to this would be towards the rear sides and back of the room where vertical and horizontal scattering / diffusion can be useful especially with surround sound systems.

[medium jim]

I'd try and keep the sound energy in the horizontal plane rather than sending it towards the ceiling and the floor. Psychoacoustically I feel that is better because it gives you more sound energy arriving from lateral angles which improves perceived soundstage spaciousness.

Maybe for conventional box speakers, for planars which are Dipole, you need to breakup the standing back waves both sideways and up and down.

Jim

[Rclark]

Yeah I've never seen 2D diffusers recommended for Maggies before, that's a first. Every Maggie system I've come across in treated rooms has 1D diffusers in the back, and are recommended.

@Nyall, thanks for stopping in. I think I'll do the QRD type. I haven't checked into a calculator yet. Is there one you can recommend or are they all the same?

Also, if I cut a pattern for an 8' * 4' diffuser, but in three sections that can be seperated, is that bad? Or should I have three seperate smaller diffusers with their own complete QRD pattern? Does that question even make sense?

@JK, thanks for the tip, I'll look into that.

[4krow]

That is a very cool and simple arrangement. In the past, I have experimented with acoustic tiles(2 per panel), and made a sort L shaped piece that could be hinged, allowing multiple angles. Placement was wherever it needed to be around the speakers with VERY good results when placed in the correct spot. Maybe I will try it again.

[medium jim]

Yeah I've never seen 2D diffusers recommended for Maggies before, that's a first. Every Maggie system I've come across in treated rooms has 1D diffusers in the back, and are recommended.

@Nyall, thanks for stopping in. I think I'll do the QRD type. I haven't checked into a calculator yet. Is there one you can recommend or are they all the same?

Also, if I cut a pattern for an 8' * 4' diffuser, and but in three sections that can be seperated, is that bad? Or should I have three seperate smaller diffusers with their own complete QRD pattern? Does that question even make sense?

@JK, thanks for the tip, I'll look into that.

Rclark:

Go to the planar porn thread, see post 10....

There are many more with similar tx.

Jim

[Rclark]

Oh thanks Jim. That's an interesting setup, I'd love to see all the different measurements he or she took to arrive at that. Most of the setups I've seen have the 1D QRD type, and from what I can remember reading from those who've tried both, they preferred the 1D qrd type for Magnepans.

I think it had to do with the 2D type dispersing too much energy, or something like that. Usually what you find is a QRD type, and they are either dead center in a broad line, or they are smaller, and placed directly behind the panels.

[Rclark]

That is a very cool and simple arrangement. In the past, I have experimented with acoustic tiles(2 per panel), and made a sort L shaped piece that could be hinged, allowing multiple angles. Placement was wherever it needed to be around the speakers with VERY good results when placed in the correct spot. Maybe I will try it again.

What sort of accoustic tiles were you using?

[PDR]

Try this one, it will do what you want.

http://www.subwoofer-builder.com/qrdude.htm

[Rclark]

thanks!

[rodge827]

Check out SLR Acoustic:

http://www.srlacoustics.com/diffusers/

The grid diffuser is $100.00 per 2' x 2' pair.

Chris

[Rclark]

Yeah, they are the company I'm most interested in for this stuff. That 8*4 foot diffuser for $600 shipped seems to be the best retail priced large diffuser going. Goal is to try and approximate that thing.

Probably going to be harder than I'm imagining it to be.

[rodge827]

Good choice. 

Allen is studio engineer and has tuned many of the studio's in and around Nashville.

[medium jim]

Good choice. 

Allen is studio engineer and has tuned many of the studio's in and around Nashville.

Rodge:

Do you by chance know Rick Vito, he's a killer guitarist and lives in Franklin....

Jim

[Alex Reynolds]

I don't think EPS will really be reflective for frequencies under about 500 Hz or so. 300 is too low an estimate I would think.
Even 6" deep wood diffusors won't work lower than 700 Hz - ish, though, so you should be okay with any regular size diffusor. I wouldn't go designing an 18" deep EPS diffusor.
If you do paint them, PAINT THEM WITH WATER BASED PAINT ONLY! Other paints will eat away the EPS.
Edit: And no, you don't need to use the mirror trick to place diffusors.

[4krow]

I was only using 2'X3' ceiling tiles. Didn't expect much, but was very surprised at the outcome. I forget the cost, but they were relatively inexpensive.

[rodge827]

Rodge:

Do you by chance know Rick Vito, he's a killer guitarist and lives in Franklin....

Jim

No I don't know him.