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Will the shape of a sealed box change the SPL or SQ?

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Old Mar 12, 2009 | 04:58 PM
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Will the shape of a sealed box change the SPL or SQ?

Hello everyone, this is my first post. It's probably been asked and answered a million times but I couldn't find a concrete answer on this forum or on the internet in general. I know that the volume is critical for proper performance but I don't know if the shape would make a difference. Some say it does, some say it doesn’t. Apparently there is a big argument over this; some saying a perfect cube is the worst speaker enclosure? I want to build a little sealed enclosure for a 10" pioneer and I'd like to know if the shape of the box would alter the SPL or SQ in any way.
Old Mar 12, 2009 | 06:12 PM
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good question, but i couldnt see how it would affect anything, its sealed. and i dont see how a square would be the worse if that what all prefabricated boxed are... but im not a pro.
Old Mar 12, 2009 | 06:45 PM
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no arguement really
large areas that reflect sound back onto the rear of a speaker is not going to improve the speakers performance, you should be able to hear it with a large flat surface one note will be emphasised over all others in that speakers range. This is why it is important to design an enclosure properly and to treat the inside to address 'standing waves'.

Not really that big a deal for a subwoofer though as the wavelength of the frequencies produced are so long. I would be more concerned with a lot of other things more than that in car audio but if you are a perfectionist... my box has no parallel surfaces.

Last edited by JohnVroom; Mar 12, 2009 at 06:48 PM.
Old Mar 12, 2009 | 06:58 PM
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SPL boxes may like the standing wave
Old Mar 13, 2009 | 12:46 AM
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I think that the perfect sub box shape would that of an egg.
But I really dont think the shape has that much of an effect on the sound.
Just make sure that the volume is correct
Old Mar 13, 2009 | 06:20 AM
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Some people argue that standing waves can also have a hand in higher levels of distortion as well. A perfect cube will reflect sound inside itself very reliably compared to something that is really oddly shaped, or has a lot of curves or braces, which is one reason some people really like fiber glass boxes.
Old Mar 14, 2009 | 12:13 PM
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Ok guys thanks for the info, I have a good idea for a box that will look good and make good use of the space in the back of my extended cab S10 and I just wanted to make sure that it wouldn't sound like crap.
Old Mar 14, 2009 | 12:24 PM
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if the rear baffle is parallel to the front baffle its not a bad thing if you have something in there to scatter the back-waves.

also it depends on the speaker, and how well designed it is to combat backwave pressure
Old Mar 14, 2009 | 12:43 PM
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Are you recommending putting something on the wall of the box that is parallel to the sub? If so what would you recommend?
Old Mar 14, 2009 | 01:33 PM
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Fibre fill, or other insulation type stuffing at least 1-2 inches thick.



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