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Valentin
03-04-2005, 11:54 AM
Does any one of you now how to make the calculations for one of these modules
i know how to do a 1D quadratic diffuser but i can not find the way to do a 2 dimension

the one i want to do is like the RPG Omniffuser

Mr. Widget
03-04-2005, 12:11 PM
For those of us that are less enlightened, what are you talking about?

I thought all of the RPG Omni-whatevers were in Iraq. You know that by asking about this stuff we're all going to be watched now.;)

Widget

Don McRitchie
03-04-2005, 12:22 PM
For those of us that are less enlightened, what are you talking about?

http://www.silentsource.com/diffusors-rpg-omniffusor.html

Alex Lancaster
03-04-2005, 12:26 PM
:) Thanks Don, it looks a little voodoo tho.

SteveW
03-04-2005, 02:02 PM
The calc's are the easy part, PM me. The harder part is proper construction.

svollmer
03-05-2005, 03:27 AM
Here is an excellent text on acoustics. Considered by many to be the bible of studio and home acoustics design.

http://www.amazon.com/exec/obidos/ASIN/0071360972/102-5843832-0468158

I am now convinced that the room acoustics do much more to/for the sound than changing electronic components, wire, cable, etc. My subs weren't doing what I expected from them, until I built some tube traps to control standing waves in the room. After that, the bass became tight, even througout the frequency range, and downright explosive.

That's just my experience, of course.

John Sheerin
03-06-2005, 05:37 PM
Calc's are in the patent.

Basically make a grid of 256 squares, then cut 256 square pieces that vary from 0 height to the maximum height. Then place them on the grid randomly. There's a formula in the patent, but it's basically a formula for placing them randomly... :>

Valentin
03-06-2005, 08:55 PM
Here is an excellent text on acoustics. Considered by many to be the bible of studio and home acoustics design.

http://www.amazon.com/exec/obidos/ASIN/0071360972/102-5843832-0468158

I am now convinced that the room acoustics do much more to/for the sound than changing electronic components, wire, cable, etc. My subs weren't doing what I expected from them, until I built some tube traps to control standing waves in the room. After that, the bass became tight, even througout the frequency range, and downright explosive.

That's just my experience, of course.

I am going in the same direction and i alsow own that book. it is ease to do the 1D Diffuser but the 2D is more cpmplex it is not just puting squers in random

dose some have a Omniffuser from rpg what i need is the aragement not since the one i plan to build are deeper

SteveW
03-07-2005, 05:58 AM
Indeed, the layout is not random. PM me with depth allowance and area to cover. Everest's book doesn't detail 2D, RPG's does. No patent on Schroeder's math - only commercial manufacture. http://www.rpginc.com/book/index.htm

Ian Mackenzie
05-16-2007, 03:30 AM
PM of you would like the spread sheet.

Not easy to make though

JBLnsince1959
05-16-2007, 05:39 AM
Indeed, the layout is not random. PM me with depth allowance and area to cover. Everest's book doesn't detail 2D, RPG's does. No patent on Schroeder's math - only commercial manufacture. http://www.rpginc.com/book/index.htm

exactly...I hadn't seen the RPG book you list and Everest's book while informative doesn't detail 2D as you mentioned..very nice info....:applaud:

If you have any more info I'll appreciate a PM also...looks like there's a new book on the horizon for me

thanks

Ian Mackenzie
05-16-2007, 07:30 AM
If you can be bothered ordering the papers some of the key points are covered in papers published in the AES journals. Most of it relates to multiple periodicity for wide coverage areas ie concert halls using phase modulated grating and other techniques and optimisiation of the diffusion scattering.

Valentin
05-16-2007, 08:46 AM
Thanks Ian and Steve

I have done my diffusers here is a picture

http://i24.photobucket.com/albums/c7/ValentinR/DSCN0058.jpg

I Will PM for the spread sheet so i can have it on my acoustics data base
thank Ian

Ian Mackenzie
05-16-2007, 03:24 PM
Hi Valentin,

You should have mail.

I think its largely an academic exercise to make a 2 D Root diffuser unless you have access to large quanitities of polystyrene foam. The device is just too heavy to make out of wood..and expensive. 20 metres for a 24x 24'' panel.

Ian