Scott Grammer

From what I've seen of FleaBay prices for Klispch crossovers, I'd have to be REAAAAAALLLY patient to get a pair for $100. But If I do see that, I'm jumping on it.

You are, of course, correct. I should have said "autoformer."

So then, the T2A is closer to being a tapped inductor than a transformer. Its primary inductance is too low to operate as a true transformer, and this relatively low inductance changes what appears (according to the schematic) to be a first-order crossover into a second-order one. That explains much. I had wondered, because a true transformer with a high enough primary inductance to draw little or no exciting current at the frequencies in question would double the apparent impedance of the midrange driver with every 3dB of output reduction, and do little else. Since the K-55-V is rated at 16 ohms, and the -6dB tap on the T2A is used, that would raise the apparent impedance to 64 ohms, which with a 4uF crossover cap would yield a slow, first-order crossover point of 620 Hz, right at the cutoff frequency of the horn. But if the T2A is acting as a parallel choke, that changes the matter entirely by raising both the crossover frequency and slope. Now I understand! Thanks for teaching me something I did not know.

I'd actually like to have a pair of T2A's, but they seem to be difficult to find. They work quite a treat controlling horn drivers. I have become convinced of that lately.

Sorry if I stepped out of bounds.

Anyone have experience in comparing the sound quality of the Crites 3636 to the Klipsch T2A autoformer? Thanks in advance.

That seems to happen more the older I get! 🤣

I've used these in a small sound reinforcement system. From about 60Hz up, they have a great deal of authority for a relatively small cabinet. I used them with satellites of my own design back in the mid 80's, crossed over at 150Hz.

I set him up with a couple of extra test kits I had. I'll suggest to him that he retest on Thursday or Friday.

Thanks.

True, and he does have a number of younger siblings around all the time. I'll be checking on him tomorrow.

So today, I came home from work early as I'm not feeling well, and my apprentice is not either. I just spoke to him by phone and he says he has tested negative for Covid, but still feels bad. I'm old and broken down, so feeling bad is not unusual for me, but he's young and strong, and for him to be feeling that rough concerns me a bit. If you are a praying person, please send up some words for Ryan's health. That said, I thought I'd take a minute to sum up this thread for any interested parties by saying that last night I made the decision to spend a fair amount of money ordering a number of parts that will be going into my Cornwalls in an attempt to make them sound more like what I want. I won't detail what I'm planning here, as such things are understandably frowned upon by the good folks who host this forum, but I will be discussing the work on my YouTube channel, the link to which can be found on my profile page. It will be a couple of weeks before work begins, as it will take a while for all the parts to arrive from the various vendors. When it's all said and done, assuming I'm happy with the outcome, I will have a lot of original Klipsch parts for sale, and I will post them here before putting them on eBay, and that way perhaps someone can repair/restore their speakers with original parts. Thanks!

One option I'm considering is along those lines, but more.... Of course, talk of modding Klipsch speakers if frowned upon here. so I'll say no more.

I'll contact SS. I use them a lot. Thanks.

I was not aware of what Modjeski had said, but for the most part, I agree. Properly functioning capacitors do not have a sound of their own, but not all caps are suitable for all functions, as Modjeski noted about the leakage of electrolytics. And I used to run a Pioneer SX-626 with cap-coupled outputs. No problem at all. Heat is indeed the enemy of caps, and most other components. I have two SX-1980's in the shop right now, and it's almost a sure bet that the voltage regulator board, which lies in the bottom center of the chassis and is loaded with poorly heat-sunk pass transistors that run really hot, will need major work in both units. The big problem with electrolytics is not that they're electrolytics, but rather that so many nowadays are cheap Chinese electrolytics. Those things are garbage. I still haven't decided what to do to the Cornwalls. But when I try something, I'll post about it here.

You know, I was thinking about those diaphragms just today. It seems to me that the phenolic diaphragms might stiffen with age, much like my knees have. Where would one find new diaphragms for this driver?

Thank you, sir.

OK, so while I have been working in audio electronics for a while (since 1977), I am the new guy here, and I understand my place as such. So I definitely would not like there to be a "capacitor war" on my account. That said, I believe there's a lot more to cap replacement in crossovers than "is the old cap really bad." Changing from bipolar electrolytics to film caps can change the sound of a speaker, and not necessarily for the better. Sometimes, a crossover designer will voice a speaker with a certain kind of caps (and inductors, as well) that have maybe a bit more than the minimum ESR (or DCR in the case of inductors). Replacing these with "better" components can change the sound of a speaker considerably. I have a pair of smaller Advents on my main workbench as test speakers, and a couple of years ago I recapped the crossovers (it was necessary, the caps were seriously leaky) and I replaced the bipolar electrolytics with thumb-sized Nichicon film caps. This got rid of the excessive midrange reaching the fried egg tweeters (which is why I checked out the crossovers in the first place), but the VERY low ESR of the Nichicons made the top end brighter than normal. I've gotten kind of used to it, but at first it was bothersome. I may still add some 1 ohm resistors in series with the tweets to tame them down. That is, if I ever have time to fool with it.... The Cornwalls I have include what I believe to be the original oil caps. They tested well, and they're not physically leaking oil (and yes, you DEFINITELY can smell it when that happens), so I don't plan on replacing them any time soon. I don't think they're the root of the problem. I will be replacing the horn gaskets soon with some supplied by a friend who used to build PA speakers, and we'll see what that does. I just have to get them - and some time - first.

Thanks for the kind words.

I actually tested the caps for value, esr, and loss, and they were a tad off. I want to keep things as stock as possible until and unless I decide to go off the deep end and do things that, as you suggested, are not to be spoken of here. 🙂 The gaskets, on the other hand, I will replace and see if that improves matters. Thanks.

Bingo. I think that may be it.

The top picture shows that your ground is not bonded to the neutral. That needs to be corrected. Could be open ground (safety hazard) or open neutral (which would cause what you're describing). In fact, since the second pic shows 88 ohms between ground and hot, I'd say something is miswired re neutral and ground.

I suspect you have a capacitive connection. That is, either hot or neutral is not actually connected, but there is enough capacitance to allow a voltage to reach the outlet that will fool a normal DVM and other voltage testers. You need to test with a low-impedance AC voltmeter, the kind that will ignore such "phantom voltage." If you don't have one, borrow one. Electricians use them to avoid scenarios like this one. These kind of things often happen because there is a long run of cable to a remote switch, and the switch has been turned off. Since the switch is off, nothing works in that outlet, but with 50 feet or sometimes more of cable going to the switch, there is enough capacitance across the open switch to allow a normal high-impedance meter to show 120V, and even enough to fool other kinds of testers. Sometimes, even LED lights will work in such an outlet due to their low current draw. The outlet may be connected to a switch you are unaware of at a remote location, and it's been turned off.

Almost as old as me!

That's possible. I believe they're probably original, and of course they would be 55 years old now. I'll pull them this weekend and take a look at them.