Guest Brian_D Posted December 10, 2003 Report Share Posted December 10, 2003 Don't get too excited!I have a pair of foam replacements for the 8" mid used in the 9 and 90.When you buy 8" surround replacements from Parts Express they send you two styles, one is very stiff and has a wide rim for adhesion, the other is less stiff and has one wide rim and one narrow. I had to buy two sets, one for my 17's one for my buddy's 18b that I refoamed and I used one of the less stiff sets for my 9's. I have left over the less stiff set from the other pair.If someone wants them, let me know. I'll even ship them cause that's the kind of guy I am I'll send the glue, dustcaps and applicators too.First come first serve! Link to comment Share on other sites More sharing options...
roundhome Posted December 10, 2003 Report Share Posted December 10, 2003 HELLO I could use them i just got my 9s out that have been boxed since 83 and well they need a foam job.If you still have them.roundhouse@sisna.comThanks Jim Link to comment Share on other sites More sharing options...
r_laski Posted December 10, 2003 Report Share Posted December 10, 2003 Brian, I’ve used the Parts Express (PE) kits to refoam 8” and 10” drivers from AR-9's and AR-9LS's. The reason they send two different types of surrounds is these are “universal” surround kits. In addition to the rim widths, you should have noticed that on one pair, both rims are flat. These work on drivers that have a flat surface on the outer rim of the cone and on the basket. On the other pair, the inner rim is angled downward. This pair is used where the cone is angled all the way to the edge and the outer rim is “flat” to the basket. This is the only one to use with AR-9/90 8” drivers. If you try to use the “flat” pair, you will either stretch the surround or get wrinkles as you try to bend the flat rim to conform to angle of the cone. The “angled” surrounds work on both the “original” AR drivers where you glue the surround to the front of the cone and the AR/Tonegen drivers where you glue the surround to the back of the cone. Since May of this year, I’ve refoamed the drivers from 4 AR-9s, 2 AR-9LSs, 2 LSTs, and 4 AR-11s. I have leftover a pair of “flat” 8” and 10” surrounds (I tossed out some of the other “flat” surrounds), 10 bottles of glue, a couple bag-fulls of swabs and dust caps, and a lifetime supply of voice coil shims. PE needs to start selling only the surrounds in addition to the kits. BTW - the AR 11" PE kit (yes we all know they are 12" woofers) has only one pair of "angled" surrounds. Rich Laski Link to comment Share on other sites More sharing options...
Guest audioslave Posted December 10, 2003 Report Share Posted December 10, 2003 > "BTW - the AR 11" PE kit (yes we all know they are 12">woofers) has only one pair of "angled" surrounds. >>Rich Laski"Rich- They actually have the "angled" foam, where the inside is angled to meet the cone on an AR 12" woofer? I have had a couple of discussions with foam suppliers and was told that the kits were made for a cone with a flat edge, and their was nothing that could be done other than to "pinch" around the inside of the foam to obtain the proper angle. One local shop owner stated that he'd "refoamed hundreds of AR 12 inch woofers from various models and have NEVER seen one that didn't have a flat edge". When I questioned this, he actually got irritated, stating that my woofers must not be original. Today, while ordering new surrounds from a different source, I asked the owner (who was well educated about early AR's) about the inside angle. His explanation was simply that more retailers asked for flat AR replacement foam versus "slightly angled" and that my most realistic option was to pinch, pinch, pinch!!!, for it was unlikely that I would find any foam that matched perfectly. I'm eager to hear your response. If Parts Express is a source for the "proper" foam, I'll need to order it. If you know of any other sources, let me know as well. My first pair of AR 9's are on their way as I type and I want to make sure I have the right foam ready to go when they arrive.Oh, did I mention I just bought a pair of AR 9's!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!JeffETA: 6 days Link to comment Share on other sites More sharing options...
Guest Brian_D Posted December 10, 2003 Report Share Posted December 10, 2003 "On the other pair, the inner rim is angled downward. This pair is used where the cone is angled all the way to the edge and the outer rim is “flat” to the basket. This is the only one to use with AR-9/90 8” drivers."Yeah, that's them... Those are the ones I used on my 9's, though I've used the other "flat" surrounds on the 17's I have at home and I didn't get any buckling or warping.I've not tackled the 12's yet, I'm dreading it a little but one of these days... Link to comment Share on other sites More sharing options...
Guest Brian_D Posted December 10, 2003 Report Share Posted December 10, 2003 Wow, that was fast.They're yours.Thanks for the comments, guys. Link to comment Share on other sites More sharing options...
r_laski Posted December 10, 2003 Report Share Posted December 10, 2003 Jeff, Congrats on acquiring a pair of AR-9s. I’m jealous!>>They actually have the "angled" foam, where the inside is angled to meet the cone on an AR 12" woofer?<< The 11” AR kit from PE (for 12” AR woofers) DEFINITELY has the inside rim angled in (down). They fit VERY nicely -- almost perfectly. I’ve now re-foamed 17 – 12”woofers with these kits in the past 6 months (it would have been 18, but one woofer voice coil was locked up and had to be taken in to be re-coned). >>Today, while ordering new surrounds from a different source, I asked the owner (who was well educated about early AR's) about the inside angle. His explanation was simply that more retailers asked for flat AR replacement foam versus "slightly angled" and that my most realistic option was to pinch, pinch, pinch!!!, for it was unlikely that I would find any foam that matched perfectly.<< If you can cancel your order, use the PE kits - you’ll need 2 kits for one pair of AR-9s. If not, “pinch, pinch, pinch!!!” Look here at what we are talking about. http://www.decware.com/dimensions.htm . BTW he sells 11” AR kits for AR 12” woofers, but his Part Number indicates a flat inner rim and they cost 2X the PE kit. Using a flat rimmed surround that is the proper size is preferable to what I saw on a pair of LST 12” woofers. The previous refoamer took oversized surrounds, cut them, and overlapped them to fit. Yes there were big warps and wrinkles in the surround rims. TIP -- If you haven’t refoamed before, start with the 8” drivers on your AR-9s. This is a good confidence builder before you tackle the 12” drivers, which can be a little intimidating the first time you try one. Rich Laski Link to comment Share on other sites More sharing options...
r_laski Posted December 10, 2003 Report Share Posted December 10, 2003 >>Yeah, that's them... Those are the ones I used on my 9's, though I've used the other "flat" surrounds on the 17's I have at home and I didn't get any buckling or warping.<<Brian, “Pinch, Pinch, Pinch” (Just kidding). I looked at the flat 8” and 10” surrounds I have. The inside rim is narrow enough and the foam resilient enough I can see how, with some pinching, (previously I called it stretching, as in stretching out the wrinkles,) you would be able to get them to conform to an angled cone without warps or wrinkles. I don’t know that I can say the same thing if you tried this on a Tonegen 8” as the surround is glued to the back of the cone - a steeper angle.>>I've not tackled the 12's yet, I'm dreading it a little but one of these days... << Because of their size, I think using a “flat” surround would be harder to get “right” on a 12” woofer before the adhesive sets up. As I stated in another post above, The PE kits for the 12” AR woofer have an angled rim and fit VERY nicely. Rich Laski Link to comment Share on other sites More sharing options...
Guest Brian_D Posted December 11, 2003 Report Share Posted December 11, 2003 When I did the 8" drivers on my 17's, I glued the surround to the woofer cone first, then the basket.This made the etire surround point upward at the same angle as the cone, but when it came time to glue to the basket, it was just a matter of rolling the angle out to make that edge flat.I know what you mean about pinch pinch pinch! I did 6 8" woofers in a 36 hour period and I was sore for a week. I figured it up; 6 8" woofers is about 300 linear inches of pinching, 4 12" woofers will be exactly the same... better get out the ice pack now.(Are we getting a little dramatic here? NAH... it's a labor of love, right?) Link to comment Share on other sites More sharing options...
Guest audioslave Posted December 11, 2003 Report Share Posted December 11, 2003 > >> If you can cancel your order, use the PE kits - you’ll need>2 kits for one pair of AR-9s. If not, “pinch, pinch,>pinch!!!”>> > I think in the future I'll have to go this route. The foam I bought cost 75-85% less than the kits PE sells, and the man I ordered them from came recommended on this forum. He kindly stated that he doesn't really sell foam, he just refoams and recones speakers, but since I called he would fulfill my foam requests. I used the flat foam when refoaming the woofers for my AR 11's and although it was more time consuming, there is no indication of stretching or warping. I'm now curious how/if the foam angle effects the woofer? I almost want to send Mr. Kantor one of the woofers refomed with the "pinched", flat surround and see if how it compares to other samples he's received. Of course, maybe Bret's refoamed specimens were refoamed using the non-angled foam. Maybe I'm just rambling and once the foam is seated correctly, regardless of angle, it doesn't make a lick of difference (given that the foam is identical with the exception of the angle). Any input?Jeff Link to comment Share on other sites More sharing options...
Guest Brian_D Posted December 11, 2003 Report Share Posted December 11, 2003 The surround actually has very little to do with compliance in these acoustic suspension systems. Early on in the design (and even in some lower-cost current designs) the spyder had more to do with motor and cone control than anything. Of course this is in addition to the enclosure (the suspension itself)Some very high-powered (and high-q and low sensitivity I might add) woofers like those used in vented subwoofers and the ever-popular car audio "boom machines" have rediculously stiff cones and therefore very stiff surrounds to aid in the control of the heavier cones.Correct me if I'm wrong, but the main purposes for the surround on an acoustic suspension system are to 1. keep the voice coil algned in the gap by limiting tilt due to cone orientation and 2. to facilitate the sealed nature of the suspension system.I would venture to say that even the very early paper acordion surrounds would perform similarly to the newer foam surrounds. (That might be going out on a limb, I'm pretty sure sensitivity would suffer, but that's about it) Link to comment Share on other sites More sharing options...
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