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View Full Version : Foam Innies ?


SEAWOLF97
04-10-2007, 12:40 PM
I'm prolly up to 20 some refoams, but have never seen "innies" before. These are ACOUSTIC's , very nice cabs , decent drivers, but the foam goes "the other way". Is this a mistake ? Is there any reason why they were done this way ? They do look original.
sourceoneaudio
04-10-2007, 12:49 PM
I have seen it b4. I also think Kef used to do it, and I have also seen it done with rubber surrounds. (Kef maybe?) 80's gear???? Been a while.

J/S-S1A :D
Zilch
04-10-2007, 01:09 PM
Original Aquaplas LE14As are "Innies," as I recall. So, yes....
zipplok
04-10-2007, 01:16 PM
I believe I have seen the foam edges applied that way on a pair of 12" Celestion woofers too.
grumpy
04-10-2007, 01:32 PM
style/differentiation.
needs less room between baffle and grille.
needs more clearance on frame.
can lay them face down when mfg.
Fangio
04-10-2007, 01:53 PM
Recently seen that on Celestions too - had a vintage pair 2-way UL6 from the 70ies here that used rubber surrounds the same way - also for the passive radiators.
clmrt
04-10-2007, 01:53 PM
Less edge diffraction?
SEAWOLF97
04-11-2007, 11:42 AM
found my EIA source code sheet - the LF marked 130 is Matsushita
grumpy
04-11-2007, 12:28 PM
aka panasonic, technics .... did I miss a segue here? :blink:
SEAWOLF97
04-11-2007, 12:52 PM
aka panasonic, technics .... did I miss a segue here? :blink:

they are marked "ACOUSTIC" ...very nice veneer, never saw Panny or Tech look this nice.
grumpy
04-11-2007, 02:45 PM
... not to be "dissing" your "ACOUSTICS"
I thought this thread was about "innies"...

I was attempting to offer additional info about your woofer:

http://en.wikipedia.org/wiki/Matsushita_Electric_Industrial_Co.
moldyoldy
04-11-2007, 10:38 PM
Can't read the designer's mind on these, but the common reason to invert the roll is to correct or tailor the overall linearity of the compliance. Both spiders and surrounds usually are non-linear, in that they resist slightly differently when moving out than in. In order to get the desired compliance, and still maintain the proper static position, sometimes it's an innie. (I suspect used most often in cases where mfrs select components from overruns, seconds, etc. for economy, then do the best they can with what they got). ;)
JBL 4645
04-13-2007, 01:10 PM
Whoa that is nasty man nasty. I had a slight slit on the (edge of the foam surrounds) on one of the JBL Control 5 and what did to keep it going just a little bit longer until I could afford to replace them with (edge rubber surrounds) or different types of JBL 6 ˝ bass mid.

Silicone flexibly rubber smoothed over the slit and it does work thou this is only temporary as it will give under strong sound pressure levels of the low end.

http://forum.stereophile.com/photopost/data/500/3677IMAG00191-med.JPG

Its messy but she’ll hold until a new slit opens up somewhere along the edge foam surround, its best to smooth it all over the wound let it dry for 1 to 2 hours and it will play “temporary” mind you.