Ajcrash Posted March 8, 2012 Share Posted March 8, 2012 I recently got a pair of KLF-20's I had a few issues with shipping damage, but I thought I had everything taken care of. I hooked them up last Friday and noticed they sounded to be lacking on the highs. Last night while looking into things for a possible sollution her on the forums I figured let me go listen to just the highs. So I switched them into just stereo so I could just hear the 20's powered things back up and the woofers are fine the tweeters are fine, but I get zero audio from the mids. When these were shipped to me both the midrange driveres were floating around inside the cabinet, one had snapped off the horn lens the other had somehow managed to come unscrewed. I got a replacement lens and thought I had everything ready to go, but obviously that's not the case. I thought perhaps with the mids floating around inside the weight of the drivers pulling on the wires had pulled away from the crossover. I just pulled one of the crosovers and everything looks to be solid, so I'm completely stumped. Short of buying 2 new crossovers from BEC just to see if that resolves the problem. Does anybody have any other sugestions or insight on what may be wrong? Quote Link to comment Share on other sites More sharing options...
moray james Posted March 8, 2012 Share Posted March 8, 2012 Reflow the solder joints at the mid diaphragms (I would also solder the spade crimps for good measure) and rflow the soldrf joints for the mid leade at the crossover. That is a good first step. It is very strange that both mids died at the same time in the same way. Try the solder and see what happens. Even if this is not the problem and it may well not be the soldering is worth doing. Get back. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
Ajcrash Posted March 8, 2012 Author Share Posted March 8, 2012 I'll give that a shot, I'm really thinking it's at the crossover though. I bought the replacement midranges and horn lenses from Jmodified and hooked those up last night as well and still got no sound from the mids. I thought perhaps it could be my speaker wires (I'm using Monster because they came with the speakers) but that doesn't seem to make any sense because the tweeters are running. I was going to switch those out to regular speaker wire and use the jumpers; but again with the tweeters running I don't think it's the speaker wire. All I have is regular solder, should I run up to the harware store and see about silver solder? Quote Link to comment Share on other sites More sharing options...
Ajcrash Posted March 8, 2012 Author Share Posted March 8, 2012 OK, now I see what is meant by reflowing. I had to check out a video on youtube. I'll have to dig around in the garage and see if I can locate my pen type soldering iron, my other one is to powerful for tight work like on the crossover. I don't think a heat gun would be precise enough to just hit the mid leads. Quote Link to comment Share on other sites More sharing options...
moray james Posted March 8, 2012 Share Posted March 8, 2012 In all likeyhood it is something stupid but you will just have to do the process of elimination. Don't by silver solder it is a pita to use and you are not experienced at soldering. Just buy some regular thin gage solder for electronics. go to a TV repair shop and buy a couple of feet fron a technician he may just give youu that much. dont use a big soldering gun use a pencil type iron with a new tip and buy some tinning compound to tin the tip with. Otherwise you will melt something and be worse off than you are now. keep us posted. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
Ajcrash Posted March 8, 2012 Author Share Posted March 8, 2012 Well, I tried a different amp, tried the different speaker wire with jumpers, still nothing. I just figured I'd try the easy stuff first troubleshooting this. Now it's on to the crossover. While not very likely to have occured to both, but I suppose it would be possible that when the drivers dropped it could have torn the wire inside the shielding. I'd probably hit the lottery before that happened though. I found the pen soldering iron in the garage so I'll work on reflowing the solder on the leads at the crossover. Quote Link to comment Share on other sites More sharing options...
Ajcrash Posted March 8, 2012 Author Share Posted March 8, 2012 Nope, that didn't get it either. I'm at a complete loss as to what the issue may be. At this point though I'm guessing a crossover replacement is going to be needed. Hopefully that will solve it, I'd hate to spend that kind of money and still not get the mids going. Quote Link to comment Share on other sites More sharing options...
moray james Posted March 8, 2012 Share Posted March 8, 2012 Ok take a battery any kind and d a click test on the mid horn diaphragms to see if they are working.This is likely something that just got changed. If you get a click from the mid horns with the battery then the horns are fine and you need to look at the crossover mid section which includes the auto transformers.Keep looking good luck. Best regards Moray James. KLF-20 schematic.pdf Quote Link to comment Share on other sites More sharing options...
Ajcrash Posted March 8, 2012 Author Share Posted March 8, 2012 I thought I had read somewhere here about not doing that? Something about if it wasn't blown before it would be after, perhaps that was just with a 9 volt. I'm assuming it may potentialy be safer to hook it up to some other speaker wire coming from my stereo in the garage since I have that option as well. If they are blown it looks like simply speakers has replacements. http://www.simplyspeakers.com/klipsch-replacement-speaker-diaphragm-127120.html I've got four different k52 drivers for these 20's the ones that came with them, and the ones I bought from Jmodified, so far none of them seem to be doing anything. Thanks by the way for your help on this. Quote Link to comment Share on other sites More sharing options...
moray james Posted March 8, 2012 Share Posted March 8, 2012 The voltage and current from a battery will not damage your speaker all it will generate is a small scratching or clicking noise (even a 9 volt) Your amp swings way more voltage. Check the drivers with either a battery or a working system set at low levels playing music so when you connect the driver you can hear it play. They should work just fine and don't worry about playing them full range at low levels it is not an issue this is just to test the voice coils which you could also do with a continuity meter (which is a nine volt battery) anything so you can eliminate the voice coils in the drivers. That done you have to look to the networks mid section. It is VERY unlikely that you have to bad diaphragms. Good luck best regards Moray James. PS: you are very welcome, you need the help I will do what I can and if we get bogged down some other far more knowlegable member will set things straight. Quote Link to comment Share on other sites More sharing options...
Mighty Favog Posted March 9, 2012 Share Posted March 9, 2012 I still wouldn't use a 9v battery. DC can be deadly to your speakers, that's the form distortion comes in. 9v DC / 2.83v DC = 3.1802 watts X 100db sens.@ 1 Khz = ~103-104db output. Uh....no. Go find a AA and use that. But, yes, while the average meter uses a 9v battery, that doesn't mean that much voltage comes out of the leads. But seriously, BEC's crossovers are well worth the cost. When I did mine the bass was more athoritative, the mids smoothed out and HF were shraper (combined with his Ti tweeters). I also rewired the insides with 12ga. Monster. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted March 9, 2012 Share Posted March 9, 2012 To test a driver I normally just hook up the speaker wire from my receiver/amp directly to the disconnected driver. Keep the volume low as you'll be sending it frequencies it can't reproduce. That will at least tell you if the driver is bad or not. I've done this countless times and never once damaged a driver. Quote Link to comment Share on other sites More sharing options...
Mighty Favog Posted March 9, 2012 Share Posted March 9, 2012 If you do it that way you could even turn down any tone controls to minimum that are under, say 1KHz. just to be safe. Quote Link to comment Share on other sites More sharing options...
Ajcrash Posted March 9, 2012 Author Share Posted March 9, 2012 Well, I just tested all 4 of the mid drivers I have on a known good setup that I have in the garage and I'm not getting any response from any of them. So I guess my next step is to order some new K-52 drivers from simply speakers and hope that resolves things. If not then I'll move on to new crossovers. Either that or I'll load them up and take the 20's down to a local vintage audio shop and see what they can come up with. I'm guessing at this point that the impacts that the drivers took in shipping is what has toasted them. Thanks for the responses guys. Quote Link to comment Share on other sites More sharing options...
moray james Posted March 9, 2012 Share Posted March 9, 2012 Ok so you connected the mid horn driver to a an amplifier playing music and you are telling me the all four motors (with diaphragms) that you have make no sound at all??? The likelihood of you having four dead diaphragms is so very small I can't believe it. There is no way that falling off and rolling around in the cabinet damaged them (I have two that did exactly this). They have likely damaged something on your crossover though like the small wire leads that stick out of the auto transformer (check them ). The impact of falling off is nothing compared to what they do every day playing music. These things are built like tanks they just don't stop in pairs for no reason. What about the back up set you have who sold you those. Did you never test them? You don't need to buy new motors just diaphragms but I just can't imagine that you really need any diaphragm. Borrow or buy a cheap multimeter. Test the voice coils to see if there is resistance or if they are open and tell me what they (the voice coils) read (measure). Is there anybody within a reasonable distance who can drive over and have a look at this situation as something is amiss? I am sure the OP would buy you a beer and cover your gas in thanks for the help. Best Regards Moray James Quote Link to comment Share on other sites More sharing options...
Ajcrash Posted March 9, 2012 Author Share Posted March 9, 2012 After looking into this further I see that getting replacement K-52 driver diaphragms from BEC would be not only cheaper, but also from a known good source. Besides I'd rather give my money to a forum member than elsewhere. I'm still not 100% certain the problem doen't lie with my crossovers though and It would truly be a bummer to buy new drivers from BEC and then have my crossover blow them. Requiring me to buy more yet more drivers and both crossovers. I know how well the KLF 20's will sound once I get things right.. it's just getting there. Lol. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted March 9, 2012 Share Posted March 9, 2012 Have you tried what moray suggested? Disconnect one of the drivers and check with an ohm meter? Quote Link to comment Share on other sites More sharing options...
Ajcrash Posted March 9, 2012 Author Share Posted March 9, 2012 On the back up set I have one is testing at 11.6 the other tests at 11.7. The ones currently in the speakers test at 11.5 and the other tests at 11.3. However, I now think I see what the issue was. And you called it Moray it's something stupid. When I reconnected the leads to the mids; because I had no idea where they went other than the yellow lead to the terminal with the yellow slash on it, and the black to the the other. I had them both connected to the same side. One to the yellow, and the black to the one right next to it rather than running the black to the opposite side of the driver. Now when I go hook this up I'm assuming on each side the connection with the yellow hash on it is going to mirror to the other side, so I'd connect the ground to the opposite terminal on the other side? Quote Link to comment Share on other sites More sharing options...
moray james Posted March 9, 2012 Share Posted March 9, 2012 The diaphragms that Bob will sell you are the new Titanium ones and they are excellent. But you still have a problem. Have you checked the four vc's that you have now and are they open or are they good??? What resistance do you read off of them? If they are good then you dont need to buy anything but you do need to track down the problem and that will be in the mid crossover section. Your KLF20 only has two parts in the mid section crossover, a 1.25 uf cap and the autotransformer that's it. If there is a problem there it has to be one part or the other. I still think this is all something simple that you are overlooking. Nobody has four voice coils go dead for no reason. You are missing something obvious. Buy or borrow a meter and check your voice coils or take the coils to an electronics supply store and ask them to check them for you it's free. You can connect a working speaker of any kind to the mid connections of your crossover to check to see if the crossover is working or not. This is not hard to do. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted March 9, 2012 Share Posted March 9, 2012 Now when I go hook this up I'm assuming on each side the connection with the yellow hash on it is going to mirror to the other side, so I'd connect the ground to the opposite terminal on the other side? If I read your response correctly, yes. You just need to make sure you don't wire them out of phase with the other drivers. Quote Link to comment Share on other sites More sharing options...
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