|
Post by robertr on Jan 17, 2007 13:50:08 GMT -7
This forum is very useful and interesting. The FAQ section states that an IB manifold should be as small as possible. However, it also states that the opening should ideally be the same size as the summed area of the drivers. Since these goals conflict, which is the more important?
|
|
|
Post by ThomasW on Jan 17, 2007 14:44:32 GMT -7
Unless there's a typo somewhere there's no mention of making manifolds as small as possible. The FAQ does says a IB manifold should be as short as possible.
|
|
|
Post by robertr on Jan 17, 2007 14:50:44 GMT -7
Sorry, when I said "small" I meant short. Keeping it short limits the opening size, yes? Would two separate short manifolds (for, say, an 8 driver IB) be preferable to one longer manifold?
|
|
|
Post by ThomasW on Jan 17, 2007 15:00:49 GMT -7
Sorry, when I said "small" I meant short. Keeping it short limits the opening size, yes? This is as short as a manifold could be for holding 18" drivers, and the opening is pretty big. The idea is to avoid having a deep manifold. So in an optimal situation two short manifolds would be better than one really deep one. Since phase issues begin to develop when the drivers are stacked one behind the other.
|
|
|
Post by robertr on Jan 17, 2007 16:37:23 GMT -7
Thanks Tom. Would putting two short manifolds together (so that they share a common wall) work?
|
|
|
Post by ThomasW on Jan 17, 2007 16:52:37 GMT -7
I can't visualize what you're talking about.
|
|
|
Post by robertr on Jan 17, 2007 17:01:49 GMT -7
Something like this: D D D D ----------------------------- : : : : : : : : : : : : : : : ----------------------------- D D D D
|
|
|
Post by ThomasW on Jan 17, 2007 17:05:55 GMT -7
Where's the opening?
|
|
|
Post by robertr on Jan 17, 2007 17:11:45 GMT -7
It's a top view. The opening is "behind" the monitor screen.
|
|
|
Post by ThomasW on Jan 17, 2007 17:31:17 GMT -7
That tells me little about where the sound exists that drawing.
|
|
|
Post by twisterz on Jan 17, 2007 18:50:41 GMT -7
Hello Thomas I think Robert is thinking of 2 of these next to each other What about one manifold with the other 4 woofers on the ends & back. A 2'X4' manifold would have an opening big enough for 8 18" woofers.
|
|
|
Post by robertr on Jan 17, 2007 20:03:54 GMT -7
You got it, Twisterz.
|
|
|
Post by chrisbee on Jan 18, 2007 5:53:54 GMT -7
Being horribly pedantic.
A 3 x 3 opposed 18" driver manifold with one driver on each end:
3 x 18" = 54" + (4 x 2" for spacing) = 62" minimum length.
1 x 18 + 4" (spacing) = 22" minimum width.
|
|