Al Klappenberger Posted July 17, 2005 Share Posted July 17, 2005 Bob, First off, I screwed up earlier. The frequency scaling I did was for 320 Hz, not 500 Hz! 5/4 versis 4/5 ratio. The values you measured are a mile off from what I expected. I have no idea what that means! All I can conclude is that I don't have all the information. Al K. Quote Link to comment Share on other sites More sharing options...
BEC Posted July 17, 2005 Author Share Posted July 17, 2005 Al, I am pretty confident on the measured inductor values. The caps, I am not too sure about. The only reasonably "good" cap is the one for the tweeter circuit which measures 3.2 uF. The dual set for the midrange is a real mess. I can only find one connection on each of those caps with no way know for sure where the other connection should be. The small cap (3.2 uF) has a foil covering on it for one side and a wire coming out of the center of the paper roll for the other side. The midrange caps have a lead connected at a point on one end of each of them, but no other connection or even a foil wrap like the 3.2 has. I expect that whoever has been into them before must have destroyed the other connection some way. There is just no trace of it. The reading I was able to take on one of them (21 uF) was from the lead on an end to a paper clip that I inserted into the center of the paper roll. I have no idea if that is even the proper place to read it. I got no reading on the other parallel cap when I tried the same thing. If there was an original marking on the caps, it is not readable now because of the tar. Bob Quote Link to comment Share on other sites More sharing options...
Deang Posted July 17, 2005 Share Posted July 17, 2005 I would stuff it full of feathers and send it back. Yeesh, what a mess. There are two on eBay right now -- and they work. Quote Link to comment Share on other sites More sharing options...
Malcolm Posted July 17, 2005 Share Posted July 17, 2005 The ones on eBay may work, as in pass a signal, but I would bet that they don't work right. If the 336 uses electrolytic caps like the other EV crossovers I have seen the insides of, they are in horrible shape by now. Quote Link to comment Share on other sites More sharing options...
BEC Posted July 17, 2005 Author Share Posted July 17, 2005 Dean, The ones you see on eBay, or at least all I have seen are the metal can type of X336. This old wood case thing is extremely rare. The metal can type are not even openable according to what I have heard. One of these things in the wood case is about the best shot at figuring out how they work. Just wish I had been the first one to open this one up. This thing just needs a few new caps if I can figure out what value they are. Slap those in and add a quart of roofing tar and this thing will be good to go. Bob Quote Link to comment Share on other sites More sharing options...
Deang Posted July 18, 2005 Share Posted July 18, 2005 I was thinking along the lines that if you had one that was actually wired correctly and worked -- you could figure out the correct values so you could fix the one you have. You know, you could contact EV direct, who might have a real schematic. Just do what I did when I called Atlas Sound a few months ago, "I want to talk to the oldest guy in the shop". Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted July 18, 2005 Share Posted July 18, 2005 Bob, I think your best bet for fixing that tar-pit is to simply redesign it! My guess is that it wasn't very good from day one anyhow! Al k. Quote Link to comment Share on other sites More sharing options...
Deang Posted July 18, 2005 Share Posted July 18, 2005 Man, that's your answer to everything! Quote Link to comment Share on other sites More sharing options...
BEC Posted July 18, 2005 Author Share Posted July 18, 2005 ---------------- On 7/18/2005 6:01:33 AM DeanG wrote: I was thinking along the lines that if you had one that was actually wired correctly and worked -- you could figure out the correct values so you could fix the one you have. You know, you could contact EV direct, who might have a real schematic. Just do what I did when I called Atlas Sound a few months ago, "I want to talk to the oldest guy in the shop". ---------------- Dean, EV is just down the road from me in Morrilton, AR. Problem is that they have very little information left in the plant that is from the old days. They are a part of Telex now and according to the manager I have talked to, most of their archive information was somehow lost when they moved the plant to Morrilton. Won't hurt to go by and ask them about this X336, but they have not been very helpful in the past when I asked them about their older products. Bob Quote Link to comment Share on other sites More sharing options...
WMcD Posted July 18, 2005 Share Posted July 18, 2005 About the woofer circuit: Based on a program here a second order Butterworth low pass filter for 300 Hz and 16 ohms uses 12.0 mH and 23.4 uF. Is that really a 2.88 mH you're measuring? Also, are you saying the caps in the woofer circuit are not installed? Edit: The lead line does not go to the text. Gil Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted July 18, 2005 Share Posted July 18, 2005 I just check Gill's numbers for the woofer filter. He's right on. Al K. Quote Link to comment Share on other sites More sharing options...
BEC Posted July 18, 2005 Author Share Posted July 18, 2005 ---------------- On 7/18/2005 4:29:29 PM William F. Gil McDermott wrote: About the woofer circuit: Based on a program here a second order Butterworth low pass filter for 300 Hz and 16 ohms uses 12.0 mH and 23.4 uF. Is that really a 2.88 mH you're measuring? Also, are you saying the caps in the woofer circuit are not intalled? Gil ---------------- Gil, Yes the woofer inductor does measure 2.88 mH. It is firmly soldered to the "LO" output so no way to mix it up as to which one it is. Yes, the woofer caps are not installed and I don't think they have ever been in the box. No place for them in the tar. As far as the value of the woofer inductor goes, I don't think the 2.5 mH that PWK used in the Heresy (700 hz), Cornwall (600 hz), Belle (500 hz) and Khorn (400 hz), ever fit the formulas either. Bob Quote Link to comment Share on other sites More sharing options...
WMcD Posted July 18, 2005 Share Posted July 18, 2005 Quite a mystery then. I do think the PWK values came close, but I'd have to check the numbers. OTOH, he did remove the inductor entirely at times in the K-Horn. So perhaps that jibes a bit with the low value, and no cap. I.e. someone may have been following that theory. Perhaps the previous owner sought out the wooden box type because the metal ones were not openable! BTW I looked at the tweeter circuit components on a simulator. With a 16 ohm load they produce a 3 dB peak at about 3 kHz. Best, Gil Quote Link to comment Share on other sites More sharing options...
BEC Posted July 18, 2005 Author Share Posted July 18, 2005 Gil, I think I may just breadboard one of these together and see how it tests on the spectrum analyzer. I should be able to try a few cap values and check out where the crossover points are. Should at least be able to see if the inductor values even work for crossing at around 300 and 3500. I spent some time talking to EV today and got nothing useful out of them. Bob Quote Link to comment Share on other sites More sharing options...
WMcD Posted July 18, 2005 Share Posted July 18, 2005 Bob, It might be worth your time to learn to work with Spice based simulators. There is some free ware out there. It is quite a challenge to ramp up to the level necessary to get results you want. Something to think about, though. Gil Quote Link to comment Share on other sites More sharing options...
BEC Posted July 18, 2005 Author Share Posted July 18, 2005 Gil, This project would likely be easier if I could just (as Al has suggested) build a workable crossover for the customer. What he really wants though is a rebuilt X336 that works exactly as it did when EV built it. I really don't think he cares that there is a perhaps better design. He is looking to keep it original and working. He even had the hope that somehow all the original parts could be made to work again. That is clearly impossible. So he would like it working with as many of the original parts as possible. I think he may also want an upgraded design later. That is almost a separate subject to him. He wants the old X336 to work again just to have it work again. Bob Quote Link to comment Share on other sites More sharing options...
BEC Posted July 25, 2005 Author Share Posted July 25, 2005 OK, I decided to put one of these things together by best guess and trial and error and have got a crossover that is very close to the known parts of the old EV X336 and it does cross at around 300 and 3500 like it is should according to my spectrum analyzer. Now I will send it to the guy to try in his Georgian to see how it actually works. If this works right in the Georgian, I should be able to fix up the old original X336. Bob Crites Quote Link to comment Share on other sites More sharing options...
EVGuy Posted July 30, 2005 Share Posted July 30, 2005 Bob, I just saw the thread about my crossover rebuild. My main needs were for a set of new crossovers like the prototype you sent me to try out. Fixing the old one was a bonus if it could be accomplished. If not, it's just going to go in my collection anyhow. The prototype seems to work good. I only have one of the Georgians in the room so I have to compare the sound of the mids and highs to my LaScalas. I think the mids are a little more pronounced than the LaScalas and sound more natural. The mid horn on a Georgian is very unusual in that from the front, you hear from 1000 hz up to 3500, and from the rear of the horn, yes there is a front and a rear horn opening, it fires 300 hz to 1000 hz through a long plastic phenolic tube, then into the large fiberglass horn which then radiates outward from the front into the room. There is an internal crossover I think I read that crosses it at 1000. My Patrician IV has two of these mid horns in it. I may want you to build me a crossover for that too which crosses at 200, 600 and 3500. Hearing what a Georgian should sound like finally, makes me wonder what the Patrician should sound like too. The old EV crossover are nice to look at but don't work too well because of their age. Bernie Quote Link to comment Share on other sites More sharing options...
BEC Posted July 30, 2005 Author Share Posted July 30, 2005 Bernie, Good to see you posting on the Klipsch forum. Bob Quote Link to comment Share on other sites More sharing options...
Deang Posted July 30, 2005 Share Posted July 30, 2005 Very nice work Bob. How's the headache? Quote Link to comment Share on other sites More sharing options...
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