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Scott Dorsey Scott Dorsey is offline
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Default Question re proper sealing of woofers with enclosure

geoff wrote:
On 9/09/2019 4:31 am, Rick Ruskin wrote:
The low end of my JBL 4315's sounds sounds less tight and defined
after having the 12" drivers refoamed. I'm wondering if this could be
do to them not being sealed tightly enough with the enclosures. Is
there any way to test for a proper seal without having to dismount
them and instal yet a another set of new seals?


The 4315 is a ported cabinet, so a slight lack of seal (unlikely anyway
as the seal is, unless broken, a continuous ring) shouldn't have a
profound effect. More likely the new foams just a little stiff and
should loosen up with a bit of use to run them in.


Agreed. But I suggest that likely the new foam is probably closer to what
JBL initially intended than the old, failing foam.

I agree that breaking them in is the first step... play some Bootsy Collins
records at high volume when you're not in the room and see if it loosens up.

BUT... if they just replaced the foam and didn't do a complete recone then
changing the foam shouldn't make a big difference in driver Fs.... most of
the resistance is coming from the spider and not from the surround.

So my guess is that you're experiencing the speakers working properly and
you're not liking that flabby JBL bass. Try moving them closer to the wall.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."