harry398 Posted February 11, 2018 Report Share Posted February 11, 2018 54 minutes ago, larrybody said: I pulled one of the Lower MidRanges out of my 9's which need new foam. They definitely have the silicone bead treatment around the inside roll. Also they are what I believe to be the correct drivers. Last year I refoamed some 200037 woofers with the same treatment. I tried to use rubber cement to recreate the bead, but found it to be too thin and runny. I wound up using some clear DAP silicone which turned out to be a bit challenging trying to figure out the correct method to apply the material. Later I did a set of AR 15 200001-1 woofers and used some filled fillet surrounds. I have about a dozen sets of JBL type 8 in.surrounds left, but for now I am using the filled fillet surrounds on anything I really care about. They do fit, although they are more difficult to position correctly. I recently re foamed a set of 200037 woofers and tried to make they look more like the 200001-1 type. I added a flat dust cap cut from a egg carton and a mesh dome cover over that. Here they are next to a 200001-1 with the regular surrounds. I plan on using some filled fillet surrounds on the AR9 LMR. A good Sunday projet maybe. the Last picture.......... what exactly are those foams? where did you buy them? do they seal tight? what glue do you use? what surrounds are you planing on using for the ar9 8 inch? thank you. Link to comment Share on other sites More sharing options...
DavidR Posted February 11, 2018 Report Share Posted February 11, 2018 Harry, that is the correct LMR driver for the 9 and 90. Does it have a square or round magnet? On my 9's one has a square magnet and the other is round. Link to comment Share on other sites More sharing options...
harry398 Posted February 11, 2018 Report Share Posted February 11, 2018 All my 8 inch ar90 and ar9 woofers are square magnet. my brother pointed out to me some other ar speakers with that bead around the inner roll area......as well as infinity speakers using that too. So there is a definite reason for that. I still want to get to the bottom of why some surrounds seal, others dont. I understand there are shades of sealing....from drum tight, to hardly any seal. How much this affects sound is unknown. Link to comment Share on other sites More sharing options...
lARrybody Posted February 11, 2018 Report Share Posted February 11, 2018 22 hours ago, harry398 said: the Last picture.......... what exactly are those foams? where did you buy them? do they seal tight? what glue do you use? what surrounds are you planing on using for the ar9 8 inch? thank you. The foams are 8 in. boston acoustics type filled fillet polyether foams. I first got them from John McPeak of msound. He is no longer in business so now I get them from Rick Cobb. Ricks part number is 610365BAF-1. I use Aleene's Tacky Glue and they seal just fine. Yes these are the surrounds I will be using on my AR9's lower midranges (200027-0) Link to comment Share on other sites More sharing options...
DavidR Posted February 12, 2018 Report Share Posted February 12, 2018 Thanks for that info Larry Link to comment Share on other sites More sharing options...
harry398 Posted February 12, 2018 Report Share Posted February 12, 2018 Thank you Larry I will contact Rick Cobb........i guess ebay is easiest....... Link to comment Share on other sites More sharing options...
lARrybody Posted February 12, 2018 Report Share Posted February 12, 2018 Rick Cobb email rcobb@tampabay.rr.com Link to comment Share on other sites More sharing options...
Pete B Posted June 20, 2018 Author Report Share Posted June 20, 2018 It looks like all the AR 8" woofers shown here are front of cone attachment for the foam, is that true for most AR woofers? Link to comment Share on other sites More sharing options...
tysontom Posted June 20, 2018 Report Share Posted June 20, 2018 On 2/10/2018 at 6:41 PM, larrybody said: I pulled one of the Lower MidRanges out of my 9's which need new foam. They definitely have the silicone bead treatment around the inside roll. Also they are what I believe to be the correct drivers. Last year I refoamed some 200037 woofers with the same treatment. I tried to use rubber cement to recreate the bead, but found it to be too thin and runny. I wound up using some clear DAP silicone which turned out to be a bit challenging trying to figure out the correct method to apply the material. Later I did a set of AR 15 200001-1 woofers and used some filled fillet surrounds. I have about a dozen sets of JBL type 8 in.surrounds left, but for now I am using the filled fillet surrounds on anything I really care about. They do fit, although they are more difficult to position correctly. I recently re foamed a set of 200037 woofers and tried to make they look more like the 200001-1 type. I added a flat dust cap cut from a egg carton and a mesh dome cover over that. Here they are next to a 200001-1 with the regular surrounds. I plan on using some filled fillet surrounds on the AR9 LMR. A good Sunday projet maybe. ________________________________________________________ That treatment ("bead") just inside the surround was a machine-applied butyl-rubber compound used on nearly every AR stamped-basket, foam-surround woofer beginning with ferrite woofers used in AR-3as, LSTs, later AR-5s, AR-6s AR-7s and so forth. It was there as an edge-damping and termination point on the cone and as part of the attachment. I don't think a newer filleted surround -- other than its compliance advantage -- offers that much improvement in edge damping. Even the bead has only a minor effect, but it was a small enhancement. An early version of that was the pre-1964 AR-3 Alnico woofers with its foam inner damping pads and the foam ring just inside the cloth surround. This outer ring was later discontinued, as it did very little to improve performance. --Tom Tyson Link to comment Share on other sites More sharing options...
ra.ra Posted June 20, 2018 Report Share Posted June 20, 2018 51 minutes ago, Pete B said: It looks like all the AR 8" woofers shown here are front of cone attachment for the foam, is that true for most AR woofers? I think you could say this is true of most, but not all 8" AR woofers. Pic attached shows new foam installed per original assembly, which had foam inner lip under paper cone of 200050 woofer. Link to comment Share on other sites More sharing options...
ra.ra Posted June 20, 2018 Report Share Posted June 20, 2018 21 minutes ago, tysontom said: AR-7 .... with original drivers and foam surrounds The treatment bead continued to be present on these Tonegen replacement woofers from a pair of AR-7's, serial numbers 20XXX. Link to comment Share on other sites More sharing options...
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