Does acoustic foam (egg crate) in speaker box count as space?

Discussion in 'Home Theater Projects' started by JesseSilver, Jul 8, 2003.

  1. JesseSilver

    JesseSilver Extra

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    In other words:
    If I have a 3 cubic foot enclosure and line the inside with 1.5" thick acoustic foam, does my enclosure now appear to be something like a 2.5 cubic foot (or whatever the math is) because I just lost 1.5" all around, OR is the foam open enough that it still counts as open space?

    Thanks!
     
  2. Jeremy Stockwell

    Jeremy Stockwell Supporting Actor

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    Jesse,

    I'm no expert, but I believe that not only would the foam stuffing count as open space, but it may effectively enlarge the enclosure slightly. I know that if you stuff the entire enclosure, you get an effective increase in enclosure volume. Lining the sides may have a similar effect to a lesser degree.

    JKS
     
  3. JesseSilver

    JesseSilver Extra

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    Yeah, that was the third unspoken option (and thanks for your reply)! What I'm planning is roughly a 2.5 cubic foot sealed sub with an AV15, stuffed with 3 lbs of polyfill and insides lined with acoustic foam. There will be a Linkwitz transform to push the Q and Fs down, but I was just trying to figure out if the foam effectively increases or decreases the apparent volume. So now we have one vote for increase. Anyone else?
     
  4. ThomasW

    ThomasW Cinematographer

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    For all intents and purposes the foam doesn't occupy enough space to be of concern.
     
  5. Mark Fitzsimmons

    Mark Fitzsimmons Supporting Actor

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    Volume increase.
     

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