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Old 20th February 2014, 01:11 AM   #1
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Default **help with design & interference/diffraction

I've been scouring the threads on this board as well as the internet and I'm having a hard time figuring out if my cabinet design is going to cause me interference or diffraction on the back end?

I'm a little new to this, so you'll have to excuse me if the answer is simple or easy to figure out/find.

Click the image to open in full size.

The black intersecting lines will be braces, but with large squares cut out to reduce internal ft^3, and keep it from being completely sectioned off...

Any help would be greatly appreciated!
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Old 20th February 2014, 03:28 AM   #2
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It is a subwoofer, the wavelengths involved are so large they won't even see the outside of your cabinet.

With 2 woofers you really should take advantage of push-push loading, it will take a BIG load off the box.

dave
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Old 20th February 2014, 05:30 AM   #3
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Quote:
Originally Posted by planet10 View Post
It is a subwoofer, the wavelengths involved are so large they won't even see the outside of your cabinet.

With 2 woofers you really should take advantage of push-push loading, it will take a BIG load off the box.

dave
Thank you for your insight.

I had considered a push-push design briefly, but the cabinet is actually for someone else who wants the finished product to look like a pixar ladybug (the speakers will be the wide eyes). I'll post a CAD/3D mock up as soon as I'm finished with it.

just to be thorough, you are saying that the spacing between each sound wave will keep it from having interference, so the alignment in this scenario isn't an issue? I assumed, because each speaker will be playing the same frequency so close to one another and angled, that it might cause some sort of cancelation...
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Old 20th February 2014, 06:25 AM   #4
laplace is offline laplace  Australia
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Angle is not relevant, it's the path-length difference between each source and the listening point. At the worst case, that's the distance between the drivers.

Given that the wavelength of 50Hz is just under 7m and your drivers are 0.3m apart, interference is not a problem - it will act as a point source. Once you get up to 550Hz, it will produce destructive interference in the lateral direction so make sure your crossover point is below 150Hz and it'll be totally fine.
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Old 21st February 2014, 10:24 PM   #5
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Quote:
Originally Posted by iFearFractals View Post
Thank you for your insight.

I had considered a push-push design briefly, but the cabinet is actually for someone else who wants the finished product to look like a pixar ladybug (the speakers will be the wide eyes). I'll post a CAD/3D mock up as soon as I'm finished with it.

just to be thorough, you are saying that the spacing between each sound wave will keep it from having interference, so the alignment in this scenario isn't an issue? I assumed, because each speaker will be playing the same frequency so close to one another and angled, that it might cause some sort of cancelation...
I am so glad the wife doesn't read these pages or I'd have another project
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Old 25th February 2014, 03:35 PM   #6
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UPDATE:

well, with the acute angle it just didn't look right face on, so I've gone back to the drawing board. Here's a quick mock up of what the finished product should look like after this revision:

Click the image to open in full size.
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Old 25th February 2014, 07:07 PM   #7
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Cool, how do the mains look
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Old 25th February 2014, 11:43 PM   #8
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Originally Posted by Phenoholic Anonymus View Post
Cool, how do the mains look
By "mains," I assume you mean the speakers themselves (if not, I apologize for being confused by the nomenclature)?

I'm repurposing two Lanzar Max 12d subwoofers. I have a shoddy trunk that is leaking, and I don't want my speakers to get ruined... so, instead of retiring them, and since my girlfriend is wanting more uumph to her the home theater, I'm creating this project around her strange aesthetic requests.

http://www.lanzar.com/el/MAX12.jpg

I'll probably put some speaker fabric/mesh over the face of the cones to hide the "Lanzar" name and insignia... not sure yet.
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Old 26th February 2014, 06:43 PM   #9
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Originally Posted by Phenoholic Anonymus View Post
Cool, how do the mains look
by 'mains' do you mean the left and right channel speakers? As of right now, they are just a simple 2way towers ( a 7" dayton, and a silk dome tweeter) painted piano black.
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Old 26th February 2014, 09:54 PM   #10
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Hi,

FYI:

b
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