djcheung Posted October 4, 2013 Report Share Posted October 4, 2013 Dear all,I have recently acquired a pair of AR93.All 6 woofers need refoaming.On the original woofers, there is a thin bead of glue on the inner roll edge of the foam surround.The glue is still flexible after all those years.The questions are :1. What is the function of this thin bead of glue2. What glue should I use to replace them3. Where can I get the glue.I hope the experts here can point me to the right direction.Best regards,David. Link to comment Share on other sites More sharing options...
JKent Posted October 5, 2013 Report Share Posted October 5, 2013 Hi DavidIf I understand your question correctly, the glue is there to make a smooth transition from the edge of the surround to the cone, so the sound waves won't hit a little ridge at the point of connection. You can get surrounds and the correct "WD" (white damper) glue, or even complete re-foam kits, from MSound. MSound is in transition now and his web site is not up and running but you can email him (John) at msound@shentel.netKent Link to comment Share on other sites More sharing options...
djcheung Posted October 10, 2013 Author Report Share Posted October 10, 2013 Hi Kent,Sorry for the late reply.The website seems to have been down for the past few days.I have already refoamed the drivers but curious about the purpose of the extra thin bead of glue on the inner edge of the roll.So it is used to smooth out the sound waves.With my untrained ears I don't think I will be able to tell the difference between with/without this extra bit of glue.I will investigate.I am located in the UK so will try to find alternatives.Thanks very much for your help.Best regards,David. Link to comment Share on other sites More sharing options...
ra.ra Posted October 10, 2013 Report Share Posted October 10, 2013 This drawing for part 200036 (AR-93 lower mid-range, flat dust cap) shows a topical "treatment" in this area, and this pic of an 8" universal replacement woofer (from an AR-7) shows a thin clear bead in roughly the same area, but it does not cover the 'little ridge' that Kent refers to where the surround sits on the cone. I, too, have been curious about this so-called "treatment". Is this what you are referring to? Link to comment Share on other sites More sharing options...
RoyC Posted October 10, 2013 Report Share Posted October 10, 2013 Hi Kent,I have already refoamed the drivers but curious about the purpose of the extra thin bead of glue on the inner edge of the roll.So it is used to smooth out the sound waves.With my untrained ears I don't think I will be able to tell the difference between with/without this extra bit of glue.Best regards,David.David,The glue was a rubber based adhesive, and it most likely served a purpose relative to damping properties of the surround/cone combination. It is unlikely you could ever duplicate it. The process of removing the old foam and glue, the properties of the new foam, and the use of new glue will have conspired to change things sufficiently to make additional glue a crapshoot. I'm certain the sonic difference at this stage of the game is insignificant.The Boston filled fillet type of surround, which I especially like to use for AR 10 inch woofers, serves a similar purpose by providing extra foam in the crease. The Boston 8 inch version does not fit as well, but will also work for AR woofers. Link to comment Share on other sites More sharing options...
djcheung Posted October 14, 2013 Author Report Share Posted October 14, 2013 Hi all,Thanks very much for your valuable information.I have one more question about the AR93 and wonder if you can help.When I took the woofers out, I have noticed that the wadding inside seems excessive - stuffed top to bottom densey.Does anybody here know exactly/roughly how much ( in weight ) of wadding should be in the cabinet ?The bass response seems weak but that may be due to the new surrounds.They do sound lovely.They sound very similar to my AR9's with less low ends.I love both of them.Best regards,David. Link to comment Share on other sites More sharing options...
RoyC Posted October 14, 2013 Report Share Posted October 14, 2013 Hi all,Thanks very much for your valuable information.I have one more question about the AR93 and wonder if you can help.When I took the woofers out, I have noticed that the wadding inside seems excessive - stuffed top to bottom densey.Does anybody here know exactly/roughly how much ( in weight ) of wadding should be in the cabinet ?The bass response seems weak but that may be due to the new surrounds.They do sound lovely.They sound very similar to my AR9's with less low ends.I love both of them.Best regards,David.I don't know the amount of material used in the 93, but these cabinets are full of poly material. It is unlikely anyone added more along the way, and the original amount is part of the design. If there really is a problem with bass response it is more likely to be woofers reconnected out of phase with each other, or the use of replacement surrounds with insufficient compliance.Since you own AR-9's, it may simply be a matter of hearing the difference between the two models.Roy Link to comment Share on other sites More sharing options...
djcheung Posted October 14, 2013 Author Report Share Posted October 14, 2013 Hi Roy,It looks like there are two different materials in it so the previous owner(s) must have added some to it.I think it may also be the new surrounds need running in a bit.I will double check to make sure that they are not connected out of phase.I don't think I can compare the two as the 9's are a bit of a beast.I will give the new surrounds another few weeks and see.Thank you very much for all your help.Best regards,David. Link to comment Share on other sites More sharing options...
Robert_S Posted October 14, 2013 Report Share Posted October 14, 2013 Does anybody here know exactly/roughly how much ( in weight ) of wadding should be in the cabinet ?According to the assembly notes for the AR-93, there should should be 20oz of finely shredded polyester, evenly distributed throughout the cabinet, with an additional 2.5oz in the midrange cavity.Robert_S Link to comment Share on other sites More sharing options...
djcheung Posted October 14, 2013 Author Report Share Posted October 14, 2013 Thanks very much Robert_S,Now I need to dig them all out and find a scale to weigh them.They look like a couple of blankets of polyester stuffed inside.A silly question.When you say finely shredded polyester, does it mean the fibre is finely shredded or the blanket of polyester needs to be broken up into pieces in order to place them evenly inside the cabinet?Best regards,David. Link to comment Share on other sites More sharing options...
Robert_S Posted October 14, 2013 Report Share Posted October 14, 2013 You're welcome David.When you say finely shredded polyester, does it mean the fibre is finely shredded or the blanket of polyester needs to be broken up into pieces in order to place them evenly inside the cabinet?I'm quoting "finely shredded" directly from the Assembly Notes:For a while I had some AR-925 (similar form factor to the AR-93), the wadding in them was the same as in my AR-915s, AR-90 and AR-18s: white polyester in soft-centered blanket form, sometimes cut into a few pieces, to more easliy enable the specified distribution I'd guess. The finely-shredded probably refers to the composition of the material.Hope that helps.Robert_S Link to comment Share on other sites More sharing options...
djcheung Posted October 15, 2013 Author Report Share Posted October 15, 2013 Hi Robert_S,I think you are right.I will get them all out this weekend and re-stuff again.I would put a picture up but can't work out how.Best regards,David. Link to comment Share on other sites More sharing options...
djcheung Posted October 17, 2013 Author Report Share Posted October 17, 2013 Hi all,Managed to dig out all of the wadding last night and weighed them.One had 4 oz over and the other 4 oz down.So I put the extra 4oz from one speaker to the other and now they have same amount of wadding in.After putting the drivers back in, I have notices that I have a slight air leak on one of of the cabinet.(Pushing one driver and observe how the other reacts).I think I need to replace the original gasket with new gasket strips ( self adhesive on one side).Should I stick the new gasket on the cabinet or on the driver basket?Best regards,David. Link to comment Share on other sites More sharing options...
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