Scott Grammer Posted July 22, 2023 Author Share Posted July 22, 2023 3 minutes ago, billybob said: Yes guess may as well check. Think you will find all is well with mid drivers. While guessing then, wish you had Klipsch mid caps for both. Don't mind me as, I try trouble shooting... @Scott Grammer Well, I did come here asking for help, so all ideas are appreciated! 1 Quote Link to comment Share on other sites More sharing options...
billybob Posted July 22, 2023 Share Posted July 22, 2023 5 minutes ago, billybob said: Yes guess may as well check. Think you will find all is well with mid drivers. While guessing then, wish you had Klipsch mid caps for both. Don't mind me as, I try trouble shooting... @Scott Grammer Cool no visible corrosion then. Since you will be checking crossover also, loosen and reseat screws on woofers, connections, speaker tabs connects. 1 Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 22, 2023 Author Share Posted July 22, 2023 9 minutes ago, billybob said: Since you will be checking crossover also, loosen and reseat screws on woofers, connections, speaker tabs connects. Will do. Already had to tighten screw terminals on the crossovers, as they were loose and causing trouble as soon as I hooked the speakers up. 1 Quote Link to comment Share on other sites More sharing options...
OO1 Posted July 22, 2023 Share Posted July 22, 2023 50 minutes ago, Scott Grammer said: I remember both of them being right at four ohms DCR, nothing wrong with the woofers , how about the tweeters and midrange drivers , did you take any readings Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 22, 2023 Author Share Posted July 22, 2023 Just now, OO1 said: nothing wrong with the woofers , how about the tweeters and midrange drivers , did you take any readings Not yet. That's coming up this weekend. I'll be taking the speakers most of the way apart to check things. Pictures and readings will be posted once I've done that. And for me, the weekend is Sunday and Monday. Quote Link to comment Share on other sites More sharing options...
Marvel Posted July 22, 2023 Share Posted July 22, 2023 Scott, loosening and retightening all the terminals on the crossover often clears up the oxidation without having to resort to Deoxit. I would perhaps check the two large caps (esr and capicitance). Caps for Klipsch Heritage are available that keep the proper transfer function as well as simply the capacitance, etc. As an aside, are you still up on Dayton Blvd? I'm down in the Ft. O/Rossville area . 1 Quote Link to comment Share on other sites More sharing options...
KT88 Posted July 22, 2023 Share Posted July 22, 2023 The caps are from two different manufacturers Mallory and Sprague, is that what Klipsch originally used? At least on one photo you can see that the solder joint on the cap doesn't really look professional. If the caps are a reason for the poor sound, polyester capacitors would be used today, as Klipsch do themselves, both for new heritage speakers and for vintage replacements, which can be bought from JEM in the correct capacities as a certified source by Klipsch. 1 Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 22, 2023 Author Share Posted July 22, 2023 (edited) So after a long day of sweating over a hot soldering iron 😆, I came home to tinker a bit with my Cornwalls. I've been experimenting with a piece of equalization software called "Equalizer APO 1.3." It runs in Windows and gives many options for EQ'ing the digital audio leaving your computer on its way to a DAC. I discovered that a simple 3dB dip, covering almost the entire range of my midrange horns, works a pretty treat. It's not exactly the sound I'm hoping for, but it's a big improvement. Tomorrow, I will be taking things apart, and I may well move the midranges down one notch on the autoformers to see what happens. The EQ software is only for experimentation, not for permanent use. It won't help when I play vinyl, for instance. Attached is the curve I've programmed into the EQ, for your edification and consideration. Edited July 22, 2023 by Scott Grammer Typos! 1 Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 22, 2023 Author Share Posted July 22, 2023 11 hours ago, KT88 said: The caps are from two different manufacturers Mallory and Sprague, is that what Klipsch originally used? At least on one photo you can see that the solder joint on the cap doesn't really look professional. If the caps are a reason for the poor sound, polyester capacitors would be used today, as Klipsch do themselves, both for new heritage speakers and for vintage replacements, which can be bought from JEM in the correct capacities as a certified source by Klipsch. I don't know if they're original or not. Tomorrow, when I open up both cabinets, I can compare the two crossovers to see if they're at least using the same components. I'm glad you noticed that - I had not. Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 23, 2023 Author Share Posted July 23, 2023 13 hours ago, Marvel said: Scott, loosening and retightening all the terminals on the crossover often clears up the oxidation without having to resort to Deoxit. I would perhaps check the two large caps (esr and capicitance). Caps for Klipsch Heritage are available that keep the proper transfer function as well as simply the capacitance, etc. As an aside, are you still up on Dayton Blvd? I'm down in the Ft. O/Rossville area . I already did the retightening bit. It was a necessity as when I first hooked them up, one woofer was not even playing. Yes, I'm still in the same place. If you look at my profile page you'll find my website, which has my shop address. Tomorrow and Monday I will be knee deep in these things, taking them mostly to bits to check everything, including the cap checks you suggest. 1 Quote Link to comment Share on other sites More sharing options...
Marvel Posted July 23, 2023 Share Posted July 23, 2023 I'm out of country for another week or so, so I won't be coming by anytime soon. 1 Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 23, 2023 Author Share Posted July 23, 2023 (edited) I've opened up the right cabinet (the previous pics were from the left) and found some interesting things. One, a really crummy-looking solder connection on the woofer (see pic). I'll fix that later. Two, the tweeter magnet is covered in a thick layer of yellow oxide which is very loosely attached, and merely touching the tweeter knocks most of it off. The screws that hold the terminal strip to the crossover, as well as one lug on the autotransformer, are similarly oxidized. The drivers all check fine for DCR and inductance, and they were wired properly in terms of phase. The connections to the autoformer match the schematics of the 'Type B" crossover. The caps both test a bit high in value, but their ESR and VLoss are fine. The woofer choke measured 2.36mH with a DCR of 0.6 ohms (about .1 ohms of that is the leads of the meter). Finally, the caps on this crossover, one a Sprague and the other a Mallory, match the crossover in the other speaker. I wonder if these were built from Klipsch components by the company that has stamped their name all over the inside of them? Comments, anyone? Edited July 23, 2023 by Scott Grammer 1 Quote Link to comment Share on other sites More sharing options...
OO1 Posted July 23, 2023 Share Posted July 23, 2023 29 minutes ago, Scott Grammer said: Comments, anyone yeah , what is the DCR for the tweeters Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 23, 2023 Author Share Posted July 23, 2023 4 minutes ago, OO1 said: yeah , what is the DCR for the tweeters 6.4 ohms per my component tester, 6.0 ohms per my ohm meter. That's just the right speaker, I have not re-opened the left speaker yet. 1 Quote Link to comment Share on other sites More sharing options...
henry4841 Posted July 23, 2023 Share Posted July 23, 2023 Scott working on old equipment myself, but only as a hobby, I have found when the capacitance increases it is a sign of the cap being tired but can still check within tolerance. I would replace them myself even if they have some limited time left. And I am not a fan of replacing caps in a crossover network just because one can. I would not give the magnetism thing another thought if they are not alnico magnets. 1 Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 23, 2023 Author Share Posted July 23, 2023 2 hours ago, henry4841 said: Scott working on old equipment myself, but only as a hobby, I have found when the capacitance increases it is a sign of the cap being tired... I agree. I do a LOT of recapping in my job, (mostly electrolytics), and when an inexpensive cap meter shows the capacitance going up, it's often due to leakage fooling the meter into thinking the cap is bigger than it is. I may do that B2 crossover after all, not only for the improvement in sound, but to replace the 55-year-old caps. I did a bit of work on both speakers, I'll post that a bit later. Right now, it's dinner time! 2 Quote Link to comment Share on other sites More sharing options...
Marvel Posted July 24, 2023 Share Posted July 24, 2023 20 hours ago, Scott Grammer said: Two, the tweeter magnet is covered in a thick layer of yellow oxide which is very loosely attached, and merely touching the tweeter knocks most of it off. I believe that's from a chromate plating done by EV. 2 Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 24, 2023 Author Share Posted July 24, 2023 OK, a bunch of stuff done, and some things figured out. I cleaned the oxidation off the tweeters and other places, checked all six drivers (all good), and added crimp-on connectors to all the wires connecting to the crossovers, to get better, more secure connections. I tried changing what taps on the autoformer the mids connect to, and was not happy, so I put them back. After reassembling the speakers (again), I stopped tinkering with them for a while and sat down with the schematic of the crossover, a calculator, and an ice-cold Coke. A bit of figuring with the old TI-30 led me to the realization that this system's impedance in the mid frequencies must be on the order of 64 ohms (!), and about 16 ohms in the top octave or so. Since the woofer has a DCR of about 3.5 ohms, and the woofer choke adds a tad to that, the low frequencies must average (not counting the two impedance peaks that occur in any vented system) about 6 ohms. That's quite a range of impedances. On an amp with tons of negative feedback, it would not matter much. But my SE tube amp has only 6dB of NFB in the output stage, and that can be dialed back to zero. The result is that it has a high output impedance, and this means that its output would fall off in the bass where the load impedance is 6 ohms, and would go up in the midrange where the load is over 60 ohms. And that, dear readers, is EXACTLY what I've been hearing. A quick hookup this morning to my 60WPC Nikko integrated amp verified my suspicions - the speakers sound very different, and the bass is excellent. So now, I have a decision or two to make.... 1 Quote Link to comment Share on other sites More sharing options...
Scott Grammer Posted July 24, 2023 Author Share Posted July 24, 2023 6 minutes ago, Marvel said: I believe that's from a chromate plating done by EV. Ahh. OK, thanks. A rag dampened with denatured alcohol cleaned them right up, easy-peasy. Stuff was going everywhere! 1 Quote Link to comment Share on other sites More sharing options...
billybob Posted July 24, 2023 Share Posted July 24, 2023 Yes I was not aware or missed about the tube amp you were using. Yes, easy to believe the Nikko SS opened up the bass. 1 Quote Link to comment Share on other sites More sharing options...
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