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ngccglp
10-28-2006, 04:14 PM
Hi,

I'm referring to the JBL enclosure guide. There is one column labelled as "Vent Area" and another labelled as "Duct Tube".

Does this mean that I EITHER choose to make a vent area in the baffle OR the equivalent number of Ducts, BUT not both?

If so, which is the preferred option?

Thanks.

Zilch
10-28-2006, 04:22 PM
No. "Vent area" tells what size the duct must be. It can be rectangular, round, or whatever shape.

"Duct tube" prescribes the length of the whatever-shaped duct.

ngccglp
10-29-2006, 02:12 AM
Thanks Zilch.

ngccglp
10-29-2006, 02:14 AM
Thanks Zilch.

Do you know how to get sealed box cabs to go down to about 40 Hz? I tried using the WinISD but not successful.

Zilch
10-29-2006, 02:27 AM
Generally speaking, larger closed boxes play lower, but cone excursion goes up.

Depends on the T/S parameters (design) of the particular driver whether you'll end up with a practical alignment....