JBryan Posted January 4, 2004 Share Posted January 4, 2004 I picked up a pr of '76 Cornwalls and I have a couple of concerns. First, one tweeter doesn't work. Well actually the tweeter works fine (I hooked it up directly) and I couldn't find any loose connections or bad solder joints so I'm wondering if it could be the cap. Its a type B xover - can someone explain how to check a cap or offer advise or suggestions that would help me diagnose where the problem is? Also, if it is a cap - where do I find a replacement? My other concern is with the woofers. The CWs have consecutive serial#s but one woofer is marked K-33B and the other is a K-33E. Other than a slightly larger dust cap on one, they look the same - same size square magnet. Could this have been done at the factory or has a woofer been replaced. Just curious and thanks in advance for the help -Bryan Quote Link to comment Share on other sites More sharing options...
garymd Posted January 4, 2004 Share Posted January 4, 2004 Bryan, Sorry but I can't answer your crossover question but my '72 heresys have the same woofer issue. In addition, one has a reddish orange surround and the other is black. I just figured one was reconed. Quote Link to comment Share on other sites More sharing options...
WMcD Posted January 6, 2004 Share Posted January 6, 2004 Hmm, maybe someone can post a schematic, I don't have one. My recall is that there is a cap feeding the autotransformer. The squarker (sp?) is fed off one tap directly. The tweeter is fed through a 2 uF cap off another tap. (Probably.) Is the squarker working? If so, the autotransformer and cap feeding it is okay. So there is some chance that 2 uF cap is open. If so, you could try putting a known good 2 uF cap across the present one. Radio Shack has 1 uF disk caps in blister caps. If you wire two in parallel you'd have a 2 uF. I have some suspicion that something else might be wrong just from the fact that you just bought it used. It is not like you know everything was in tip top shape beforehand. A schematic will surface. Then check that it is wired correctly. Good luck, Gil Quote Link to comment Share on other sites More sharing options...
JohnA Posted January 6, 2004 Share Posted January 6, 2004 Here ya go! I have a volt meter that can test caps, but in lieu of that, clip jumpers across the 2 uF cap to the tweeter, it it works, the cap is bad. If not, suspect the autformer winding for the tweeter. To test that, unsolder the lead and clip it to the squawker's autoformer terminal. If it works then, you need a new autoformer. Klipsch will sell you one, I think. And there is another source, if necessary. Do yourself a favor and use Hovland Musicaps for replacements. The 2uF Aerovox motor-start caps are no longer in production. Your woofers are different because one K-33-B was fried and replaced with a newer K-33-E. The -E is better in the bass horns. I'm not sure about a Cornwall. Quote Link to comment Share on other sites More sharing options...
JBryan Posted January 7, 2004 Author Share Posted January 7, 2004 "I have a volt meter that can test caps, but in lieu of that, clip jumpers across the 2 uF cap to the tweeter, it it works, the cap is bad. If not, suspect the autformer winding for the tweeter. To test that, unsolder the lead and clip it to the squawker's autoformer terminal. If it works then, you need a new autoformer. Klipsch will sell you one, I think. And there is another source, if necessary. " Thanks John, I'll bypass the cap and hope that's the problem as I don't particularly want to source another autoformer. I have several caps which can replace the existing 2uf and I guess I'll end up replacing the matching cap in the other xover so I maintain balance between the speakers. I have a Hickok tester that tests caps but I've never tried it on a cap in a network and don't know if that would skew the measurements - although I would think it'd have to. Could I just test for continuity between the leads or is it necessary to desolder first? As you may have ascertained, I'm trying to avoid pulling out an iron if at all posssible. Thanks again for your help and I will let you know how it woks out. -Bryan Quote Link to comment Share on other sites More sharing options...
ricktate Posted January 7, 2004 Share Posted January 7, 2004 You can get the autoformer from company in Texas that makes them.....AL K. has address on his ALK site...rick Quote Link to comment Share on other sites More sharing options...
WMcD Posted January 7, 2004 Share Posted January 7, 2004 Yes I'm quite certain that the cap must be disconneced from the rest of the network for proper testing. BUT, that means really that only one lead must be disconnected. So if you disconnect the tweeter, and just the "red" or "plus" side you can test the 2 uF cap. Thanks for the schematic John. Gil Quote Link to comment Share on other sites More sharing options...
JBryan Posted January 10, 2004 Author Share Posted January 10, 2004 I tried another approach and determined that it is definitely a bad tweeter. I removed it from the network and hooked it up - NOTHING. I guess its blown and needs a new diaphram but I'll have to try a few tricks first. Any suggestions? I read in the archives that someone in FL supplies them at a reasonable cost but don't have the contact info. Does anyone have that fellows info or know a good source? Thanks for all you help -Bryan Quote Link to comment Share on other sites More sharing options...
garymd Posted January 10, 2004 Share Posted January 10, 2004 Bryan, I have 2 spares here (actually they're in speakers I'm not using at the moment - not klipsch). You should be able to find a kit or a new one pretty easily but you're welcome to borrow one of my spare EV-T35s in the meantime. It would be no problem whatsoever. Quote Link to comment Share on other sites More sharing options...
JBryan Posted January 11, 2004 Author Share Posted January 11, 2004 Thanks for the offer Gary but I don't plan on hanging onto these CWs very long. I bought them for a friend who is unable to repair them. I'll take a look at the tweeter (K-77M) tonight or (yawn!) tomorrow and hopefully I can source the part(s) and get these puppies out of here before the weekend. Thanks again, Bryan Quote Link to comment Share on other sites More sharing options...
garymd Posted January 11, 2004 Share Posted January 11, 2004 ---------------- On 1/11/2004 12:00:48 AM JBryan wrote: Thanks for the offer Gary but I don't plan on hanging onto these CWs very long. I bought them for a friend who is unable to repair them. I'll take a look at the tweeter (K-77M) tonight or (yawn!) tomorrow and hopefully I can source the part(s) and get these puppies out of here before the weekend. Thanks again, Bryan ---------------- Bryan, The EV-T35 and the K-77 are one in the same. If you can find a T35 on ebay, it'll work. Good luck. Is your friend taking them anyway? You're not stuck with them, are you? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 11, 2004 Share Posted January 11, 2004 Gary, will those tweeters work for the 86 cornwall II's, I am pretty shure the tweets are BLOWN please let me know Smilin Quote Link to comment Share on other sites More sharing options...
louis Posted January 11, 2004 Share Posted January 11, 2004 YOU CAN GET DIAGRAPHMS FROM BOBCRITES@CENTURYTEL.NET HE SELLS ON EBAY ALSO POSTS ON FORUM AND HAS LINK HOW TO PUT IN Quote Link to comment Share on other sites More sharing options...
garymd Posted January 11, 2004 Share Posted January 11, 2004 ---------------- On 1/11/2004 1:22:07 AM smilin wrote: Gary, will those tweeters work for the 86 cornwall II's, I am pretty shure the tweets are BLOWN please let me know Smilin ---------------- No. You need front mounted tweets for CWIIs. Sorry dude. Quote Link to comment Share on other sites More sharing options...
3dzapper Posted January 12, 2004 Share Posted January 12, 2004 Gary, same tweeters just mounted differantly. Brian, You can call Klipsch or email Bob Crites at bobcrites@centurytel.net. The diaphrams are easy to replace. Rick Quote Link to comment Share on other sites More sharing options...
djk Posted January 12, 2004 Share Posted January 12, 2004 "Gary, same tweeters just mounted differantly." ABSOLUTELY NOT ! The Cornwall uses the K77, after about 1985 the Cornwall II uses the K79. The Klipsch PN on the replacement diaphragm is 127103 and Klipsch will sell you one for about $20. I recommend you buy a pair and save the original as a spare. Quote Link to comment Share on other sites More sharing options...
JBryan Posted January 14, 2004 Author Share Posted January 14, 2004 Guys, Thanks for all your help. I spoke with Bob Crites yesterday and ordered a diaphragm from him. He shipped it out the same day. I'll install it as soon as I get it and hopefully get the CWs out of the house pronto. Thanks again! Bryan Quote Link to comment Share on other sites More sharing options...
garymd Posted January 14, 2004 Share Posted January 14, 2004 ---------------- On 1/14/2004 9:32:35 AM JBryan wrote: Guys, Thanks for all your help. I spoke with Bob Crites yesterday and ordered a diaphragm from him. He shipped it out the same day. I'll install it as soon as I get it and hopefully get the CWs out of the house pronto. Thanks again! Bryan ---------------- You seem very eager to dump those CWs! Taking up space? You mentioned they are going to a friend. If you don't mind me asking, what's the deal? Just curious. Quote Link to comment Share on other sites More sharing options...
triceratops Posted January 23, 2004 Share Posted January 23, 2004 Smilin' I think some folks are confused about which Cornwalls you have. The ones you bought off Ebay with the vertical horns (as I recall) are 1970's Cornwall II. On this vintage the "II" is a diagrammatic representation of the squawker and tweeter mounted in vertical position. This model used the traditional K-77 tweeter (EV T-35)which was rear mounted on the motorboard. After 1985, the later Cornwall II was produced, which used the different K-79 tweeter which was front-mounted on the motorboard. That's why some are saying that your speakers use a different tweeter. It's a shame that the company apparently forgot that the Cornwall II nomenclature had been used years before and used it again in the 1980's. It always causes confusion. Best in horns, triceratops Quote Link to comment Share on other sites More sharing options...
IndyKlipschFan Posted January 24, 2004 Share Posted January 24, 2004 Very true smilin...think of yours as cornwall ones for the room. Your tweeters are in fact mounted from the inside. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.