Box bracing

Discussion in 'DIY Speaker & Subwoofer Building' started by mr yonex, Feb 17, 2014.

  1. mr yonex

    mr yonex
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    Are there any guides as to how big an enclosure needs to be before bracing is required and how much bracing/what type is required? I have read around on the American forums but can't really find any definitive answers...

    Ed
     
  2. MemX

    MemX
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    I think I've read a few things, such as always brace big panels, try to vary the size of unbraced areas to vary the resonance frequencies of them and therefore avoid one massive box resonance frequency, and to do them something like every 7 inches, although you can just use dowelling rods to tie opposite sides together.

    I think?? lol
     
  3. mr yonex

    mr yonex
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    Thanks for your reply. Not definitive answers, but does make sense in theory. I was hoping someone who has built a few boxes could advice on what has worked for them. Geckodan perhaps?
     
  4. scottthehat

    scottthehat
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    I used no bracing in my cabinet just 25mm thick mdf and 50mm front, and a 20" cube its solid,
     
  5. KelvinS1965

    KelvinS1965
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    I got Gordy to put bracing in my pair of 19" cubed boxes. They are just pieces of the same 25mm MDF in a cross section half way into the enclosure (far enough back to clear the magnet on the Fi Q series driver I'm using). I also went for double thickness 50mm front baffle like Scott. I don't know how much more it cost as I didn't ask for a non braced price, but I didn't see it was worth skimping for the sake of a few pounds. The cabinets are really solid and the only rattles I've heard have been from the furniture and living room door, so I need to go round with some blutak and some wood screws I think. :)

    I suppose in theory I've lost a small amount of cabinet volume doing this, but they seem to work really well anyway.
     
  6. mr yonex

    mr yonex
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    Thanks for the replies. With my proposed ported box being around 5cuft I think I may need to add some bracing.
     

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