Lucky Pierre Posted July 7 Report Share Posted July 7 Greetings, Hope you are all staying cool. Per my earlier thread, I replaced the rock wool in my 3s with 23 oz fiberglass, and replaced the pots with new ones (thanks Jkent!) The speakers were recapped a number of years ago. The new pots work great. Upon testing, however, I am getting a crunchiness from one of the woofers, but only at high volume. There is no noticeable VC rub, and I tried installing the woofer 180 degrees, to no avail. These have been out of service for a couple of years, due to pot failure. I don't think the crunchiness was there before, but I was not able to really play them loud in the last house. Any ideas? TIA, Peter Quote Link to comment Share on other sites More sharing options...
meta_noia_fot Posted July 7 Report Share Posted July 7 I’d check to make sure the cone is still properly attached to the spider. I’ve gotten a crunchy rattle before when those have separated. Quote Link to comment Share on other sites More sharing options...
Lucky Pierre Posted July 7 Author Report Share Posted July 7 1 hour ago, meta_noia_fot said: I’d check to make sure the cone is still properly attached to the spider. I’ve gotten a crunchy rattle before when those have separated. I'll have to check that tomorrow. The shop is a bit hot and I don't feel like getting back into the speakers today. Quote Link to comment Share on other sites More sharing options...
Lucky Pierre Posted July 7 Author Report Share Posted July 7 I checked. The spider is properly attached to the cone. Quote Link to comment Share on other sites More sharing options...
newandold Posted July 8 Report Share Posted July 8 After 60+ years the voice coil could be giving it up in that driver Quote Link to comment Share on other sites More sharing options...
frankmarsi Posted July 8 Report Share Posted July 8 Two other possibilities could be the voice is out of alignment or, the tinsel leads may be pulled too tight or short or kinked. Or cabinet is lacking the proper amount of interior stuffing. And lastly an air leak of the cabinet's suspension seal. Measurement, trial and error both in listening and physical inspection will turn up the answer for certain. Although age and use could be the cause however, other than what has been mentioned, the AR woofer is a rather hardy driver. Whatever the reason nor however strong the AR driver is, it has not stopped me from stocking spare 12 inch woofers. In 1978 I blew-out a woofer for the first time and the feeling inside my gut of being abandoned and helpless knowing these woofers are not stocked or pulled from a shelve for purchase from any store except being purchased directly from AR was very unsettling. Worse yet, these days there's no more AR Corp. so, used purchases is the only way to go and in all likelihood the direction one takes. Ultimately, the directive is to get the speaker up and running whatever it takes. Good condition used drivers or total driver rebuild is our only form of insurance in keeping these older speakers alive. After years of ownership, I can admit, owners are very limited in their options. But, if you are dedicated as I have been all these decades, it should be a labor of love eternal. FM 68 Quote Link to comment Share on other sites More sharing options...
ReliaBill Engineer Posted July 8 Report Share Posted July 8 Check the masonite spacer ring on the outer edge of the woofer surround, front face. Gently pry up on it, all the way around it. Make SURE it’s secure. Not uncommon for the original glue to fail; I had to repair both of mine, after hearing that “crunchiness” at higher volumes.The glue had disintegrated and was allowing that masonite ring to “flop” At high volume levels. Quote Link to comment Share on other sites More sharing options...
Lucky Pierre Posted July 8 Author Report Share Posted July 8 (edited) 34 minutes ago, ReliaBill Engineer said: Check the masonite spacer ring on the outer edge of the woofer surround, front face. Gently pry up on it, all the way around it. Make SURE it’s secure. Not uncommon for the original glue to fail; I had to repair both of mine, after hearing that “crunchiness” at higher volumes.The glue had disintegrated and was allowing that masonite ring to “flop” At high volume levels. Ding! Ding! Ding! The masonite ring has become unglued about 1/3 way around the basket. What is the proper glue to use? I have Aleene's Tacky glue (PVA). I also may have leftover PVA glue from Simply speakers for surrounds, and maybe some two part epoxy. Would it be reasonable for me to reglue the 1/3 where it has lifted, let that fully cure, then work my way around in 1/3 increments and reglue the whole ring? Edited July 8 by Lucky Pierre misspelled "cure" Quote Link to comment Share on other sites More sharing options...
ReliaBill Engineer Posted July 8 Report Share Posted July 8 I just went ahead and loosened the ring all the way around. I used the black paint ring as a guide to glue it back in place exactly where it was. I used Gorilla Glue, because that’s what I had. It’s a very good glue; dries clear and hard. I let it cure 24 hours before powering up the woofers. Quote Link to comment Share on other sites More sharing options...
GD70 Posted July 27 Report Share Posted July 27 On 7/8/2024 at 1:33 PM, Lucky Pierre said: Ding! Ding! Ding! The masonite ring has become unglued about 1/3 way around the basket. What is the proper glue to use? I have Aleene's Tacky glue (PVA). I also may have leftover PVA glue from Simply speakers for surrounds, and maybe some two part epoxy. Would it be reasonable for me to reglue the 1/3 where it has lifted, let that fully cure, then work my way around in 1/3 increments and reglue the whole ring? Hey Peter, I hope all is well with you and your family! I’m assuming you have fixed these since the last post? If not, Aileen’s will work fine. Stay cool! Cheers, Glenn Quote Link to comment Share on other sites More sharing options...
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