klipschhornfan Posted April 23, 2019 Share Posted April 23, 2019 My pair of Heresy I comes with K22-E alnico woofers. They are 40+ years old. I'm wondering if the accordion woofer surrounds will dry rot like other vintage woofers with rubber surrounds. If something breaks down in these vintage woofers due to aging, what usually goes first? These speakers like to be played loud. Is it possible to have too much woofer excursion resulting in damage? I'm driving them with 11W SET tube amp. Is it too little power to worry about damaging the drivers? Thanks. Quote Link to comment Share on other sites More sharing options...
ricktate Posted April 23, 2019 Share Posted April 23, 2019 Those are not rubber....so dont worry about it. But if you want to try new ones Bon Crites has them. Quote Link to comment Share on other sites More sharing options...
glens Posted April 23, 2019 Share Posted April 23, 2019 I doubt 11 Watts would be much cause for concern, but Alnico's magnetic strength is known to weaken when subjected to at least high currents in the voice coil. I don't know how or whether time in and of itself takes a toll. But they can be re-energized in any event. Quote Link to comment Share on other sites More sharing options...
klipschhornfan Posted April 23, 2019 Author Share Posted April 23, 2019 8 minutes ago, glens said: I doubt 11 Watts would be much cause for concern, but Alnico's magnetic strength is known to weaken when subjected to at least high currents in the voice coil. I don't know how or whether time in and of itself takes a toll. But they can be re-energized in any event. How can I tell if the alnico drivers are out of spec? The speakers sound great to my ears. Quote Link to comment Share on other sites More sharing options...
glens Posted April 23, 2019 Share Posted April 23, 2019 I can't answer that. You'd need the specs and instrumentation. Like I said, if all you ever throw at them is 11 watts they're most likely just fine. Quote Link to comment Share on other sites More sharing options...
JohnA Posted April 23, 2019 Share Posted April 23, 2019 9 hours ago, klipschhornfan said: My pair of Heresy I comes with K22-E alnico woofers. They are 40+ years old. I'm wondering if the accordion woofer surrounds will dry rot like other vintage woofers with rubber surrounds. If something breaks down in these vintage woofers due to aging, what usually goes first? These speakers like to be played loud. Is it possible to have too much woofer excursion resulting in damage? I'm driving them with 11W SET tube amp. Is it too little power to worry about damaging the drivers? Thanks. 11 watts (what tubes get 11 watts SET?) is too little to worry about driver damage, save the tweeter, maybe. Watch out for electronic squeaks and pops fooling with the inputs while the power is on. I have a '67 and a '68 H700 with AlNiCo E-V woofers, still woofing nicely. The spider and surround are in good shape. The treated cloth does not breakdown like the '80s foam surrounds. AlNiCo magnets can lose strength from mechanical shock, high EM field strength and heat. Possibly age. Only detailed testing can determine if the magnet is weak. If you can't hear anything, I'm sure they're fine. Only a speaker maker would have the device to magnetize the woofer, like Great Plains Audio. The machine appears to need a cavity shaped to the particular driver. Since your woofer is a -E, look for a 67- manufacturer code. If it has that it is made by Eminence and you can call them to see what they say. Quote Link to comment Share on other sites More sharing options...
donmark Posted April 24, 2019 Share Posted April 24, 2019 I got a pair of 22s in my Heresies that I am am freshening up.The only thing that I noticed on inspection was that the cloth surround was rather dry to the touch compared to my GPA414s. But they were much newer.Wonder if they should be treated once in a while. At least the surrounds don’t rot.To counter potential sag from 40 years of gravity I Did considered monting the woofers upsidedown when putting them back in the cab. But the leads didn’t reach far enough to get to the crossover so I dropped the idea.They sound great anywaySent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
klipschhornfan Posted April 24, 2019 Author Share Posted April 24, 2019 18 hours ago, JohnA said: Since your woofer is a -E, look for a 67- manufacturer code. If it has that it is made by Eminence and you can call them to see what they say. I only see a 4-digit code on my K22-E. Quote Link to comment Share on other sites More sharing options...
JohnA Posted April 24, 2019 Share Posted April 24, 2019 That's a Klipsch number. Look elsewhere on the woofer for something like 67-7219, the 19th week of 1972, made by Eminence. Quote Link to comment Share on other sites More sharing options...
Escher Posted April 24, 2019 Share Posted April 24, 2019 On 4/23/2019 at 8:12 AM, klipschhornfan said: How can I tell if the alnico drivers are out of spec? The speakers sound great to my ears. I think you answered your own question... The old adage applies - "If it ain't broke..." Now if you want to upgrade or play with rolling drivers - that's another thing entirely! Quote Link to comment Share on other sites More sharing options...
moray james Posted April 24, 2019 Share Posted April 24, 2019 the reason that Alnico drives can lose magnetic charge is because of heat build up this can occur most often by pro use at very high play levels. If you are concerned you could always send the drivers to Great Plains Audio who are Altec and they can recharge your woofer to as new condition. If your drivers have not suffered hard use they may be fine. If they sound good to you why worry? You might rather pend the money on a pair of subs. Be careful while visiting the Altec site as those drivers can lead you down the path to the dark side of the Lansing Heritage as drivers designed by James B. Lansing will steal you away from the Klipsch light in which you are basking at the moment, such is their tremendous design and build quality. https://greatplainsaudio.com/ 1 Quote Link to comment Share on other sites More sharing options...
klipschhornfan Posted May 2, 2019 Author Share Posted May 2, 2019 BTW, what are the end caps for on these alnico magnets? Quote Link to comment Share on other sites More sharing options...
JohnA Posted May 2, 2019 Share Posted May 2, 2019 Aluminum? Looks like the code I mentioned is under the Klipsch badge. Quote Link to comment Share on other sites More sharing options...
klipschhornfan Posted May 2, 2019 Author Share Posted May 2, 2019 1 minute ago, JohnA said: Aluminum? Looks like the code I mentioned is under the Klipsch badge. Those woofers are not mine. I'm just curious what those alnico manget caps are for as they are not on mine. Quote Link to comment Share on other sites More sharing options...
JohnA Posted May 2, 2019 Share Posted May 2, 2019 Dust covers, I'd say. Quote Link to comment Share on other sites More sharing options...
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