T.H.E. Droid Posted August 17, 2011 Share Posted August 17, 2011 I finally got around to buying a pair of Khorns about a month ago. I've wanted a set since I bought my first Klipsch speakers (LaScalas) back in 1975. This is a 1980's set with K77m tweeters, K55M midrange, AK3 crossovers. One of the tweeters was dead (open voice coil) so I ordered CT125 replacement tweeters and a 4500 hz crossover from Bob Crites. Upon receipt of the new parts, I removed the old crossover components and rewired the bass sections, which originally contained the bass low pass section inside the cabinet. I put in the new tweeters. On first testing, I felt the midrange and highs were far too "hot" for my taste and inserted 16 ohm and 8 ohm into the mid and high frequency circuits. I'm driving the speakers with an Adcom system-- 5500 amp, with adcom CD and preamp. My other audio components-- a pair of JBL Summit speakers, and a pair of 1984 Cornwalls with Crites rebuilt crossover. To make a long story longer, these Khorns sound absolutely awful. Frankly, I've never heard Khorns before, so I can only compare them with my other speakers. I've checked the bass drivers and they seem fine, with similar resistance readings. Their suspensiones and cones are fine and they are firmly mounted. The bass is exactly the opposite of what I expected. It is bloated, thumpy, crude and has a wooden conga sound that is overpowering. For example, in Carmina Burana's Oh Fortuna where the drums come in strong, they overpower everything else so strongly (and with such an awful sound) that you have to jump up and turn down the volume. I get the same effect with a track like Williams "Star Wars" theme (OSR) where kettle drums overpower everything else. It sounds like the bass section is reproducing far too high a frequency range. This effect is even more pronounced without the L-pads installed. These speakers sound like cheap, thumping garage sale no-brands. The midrange is strong and reedy, which I associate with the horn type speakers. The highs are decent too. Overall, though, the mid/highs lack the fine detail and crispness that I associate with horn speakers. In comparison, the JBL's and Cornwalls have a very clean, clear deep bass with no overtones, crisp highly detailed midrange, and clean highs. The khorns are in good mechanical condition, with clean cabinets and good joints. I can't find anythying to explain why they sound like this and I can't believe this design could sound like this and be successful for so long, so I'm assuming something is wrong. Any suggestions on how to troubleshoot? Quote Link to comment Share on other sites More sharing options...
jcmusic Posted August 17, 2011 Share Posted August 17, 2011 Do you have them firmly into the corners of your room??? If not start there!!! Jay Quote Link to comment Share on other sites More sharing options...
mark1101 Posted August 17, 2011 Share Posted August 17, 2011 ...........well you modded them before you ever got a baseline of the original sound. So now it is going to be a little more difficult to troubleshoot. Personally, I think you ought to put them back to original and send Bob Crites the tweeters and let him replace the brokens parts...........and recap your original croosovers. That would make the speakers very close to original sound from the factory. Did you wire in the new crossovers correctly..........and rewire the bass cabinet components correctly? I'd recheck that stuff. Can you adjust the output of the drivers on the autoformers? I think you can. I'd check that too. You mention "adding 16 ohm and 8 ohm into the mid and high circuits." That makes no sense. What did you do? Are they setup tightly into good corners of the room? Can you describe the room and physical setup? You mention cornwalls. Does your equipment (amp/preamp) sound good on those? These are a few things to check and to consider. Quote Link to comment Share on other sites More sharing options...
mark1101 Posted August 17, 2011 Share Posted August 17, 2011 What are the serial numbers of each speaker? They sound like they may be newer than 80s. Quote Link to comment Share on other sites More sharing options...
LarryC Posted August 17, 2011 Share Posted August 17, 2011 Mark's recommendations are good, but, because there are so many problem possibilities, I think you might call Bob Crites and have him guide you through a troubleshooting process. Good luck! Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted August 17, 2011 Share Posted August 17, 2011 Before you go too far, I would suggest letting us know where you live. With that, you can probably get an invitation from someone who owns a pair of Klipschorns that has them set up properly in corners. Then let us know what you think about the "Klipschorn sound", it may not be your cup of tea. While you are waiting, take the above advice from others. Are the drivers wired correctly (polarity), are they snug in the corners (search the threads for "pipe foam"), was the bass bin access panel sealed tightly when you were fooling around with the crossovers? Have you tried them in different corners? Get rid of the resistors and pads (if you must tinker, then use other taps on the autoformer). How old are the diaphragms on the K-55? Good luck! Quote Link to comment Share on other sites More sharing options...
fini Posted August 17, 2011 Share Posted August 17, 2011 Wow, less than 45 minutes after posting (for the first time), and he's got 6 well-intentioned replies! Great forum, eh? Definitely something's wrong, especially if you think the bass is bloated compared to the Cornwall. Quote Link to comment Share on other sites More sharing options...
T.H.E. Droid Posted August 17, 2011 Author Share Posted August 17, 2011 It's a great response and here is some more information: I mentioned 8 and 16 ohms, without adding "L pads". They are connected properly and the problems are as described regardless of whether the pads are in the circuit or not. I'm a retired electrical engineer so I'm familiar with proper wiring and phasing of components. Drivers are all hooked up pos/neg as per their contact markings or the original connection. (no plus/minus markings on the woofers but one side goes to what is obviously the "common" side of the fuse/interconnect panel and crossover, so that was connected to minus on the crossovers. The bass doesn't seem out of phase (no hole in the middle and it does present a discernable soundstage) but has that woody sound. They are plugged as tightly into the corners as I can get them and I do have two very good drywall corners to use. To answer some other questions: Bob can't fix the bad tweeter because the diaphragms are not available. My other speakers sound great on the same system. As I mentioned, I can A/B them without much trouble. Even an old pair of Bose 901 series twos sounds better. I have talked to Bob about the level issue and autotransformer and he advised against changing taps on the autotransformer because that changes the crossover frequencies. (He also advised against using L-pads but you know, my JBL Summits have them and they sound great, but I did need to adjust them to get the best sound to suit my ears, so I think the benefit outweights the risk. ) I'm confused as to the risk from not having the cabinets tightly sealed into the corners. I bought a pair of speakerlab K's for my uncle and he doesn't even have them in a corner at all and they sound ten times better, and without the wood resonance. If uncoupling from the corner can disturb the frequency characteristics of a khorn that much, I would think his should sound even worse. In other words, I don't want to go to elaborate extremes to couple these into the corners if it doesn't solve the problem. I live north of Detroit so being able to hear a pair of properly set up speakers with the same source material would be a great help. Some other things I'm going to more thoroughly investigate are the bass drivers and their seals, the seals of the cabinets (I need to flip them over and make sure some dummy didn't drill 4" holes in the bottoms to let water get out) and I'll probably send my mid horns/crossovers/HF drivers to Bob for evaluation. Given some of the rigs you folks are running, I'm sure you'd clap your hands over your ears and run out of the room when listening to these speakers and I know they can't possibly be sounding right. So keep the suggestions coming and I'll keep you posted on what I find out. I'll put up the serial numbers when I can speakers out and check them. Quote Link to comment Share on other sites More sharing options...
Ave Bona Cornwall Posted August 17, 2011 Share Posted August 17, 2011 What are the serial numbers of each speaker? They sound like they may be newer than 80s.[Y]Not that it is that important to the problem, but who knows. I think AK-3 networks weren't around in 1980. Quote Link to comment Share on other sites More sharing options...
mark1101 Posted August 17, 2011 Share Posted August 17, 2011 It could be that the Ks don't like the high powered Adcom solid state amp. I've had that happen before. Ks like tubes and warm sounding usually lower powered solid state. It's not a hard and fast rule............but pretty close. Do you have another amp to try? Does it sound like the woofers are loose (vibrating in the cabinet) or distorting (bottoming out)? You hardly ever see bass complaints about Khorns on this forum..........it is usually the mid-horn and the tweeters that generate the most complaints if any. Can you post pics of the crossover so we can see how you wired it and the taps being used? I know you know your stuff...........but you really need to be sure about the wiring first. Quote Link to comment Share on other sites More sharing options...
mark1101 Posted August 17, 2011 Share Posted August 17, 2011 Did you install the jumper from the HF input to the LF input on teh crossover? Quote Link to comment Share on other sites More sharing options...
T.H.E. Droid Posted August 17, 2011 Author Share Posted August 17, 2011 What are the serial numbers of each speaker? They sound like they may be newer than 80s. Not that it is that important to the problem, but who knows. I think AK-3 networks weren't around in 1980. Sorry, I got out the box I put them in and they are AK-2 crossovers. And I will add that my uncle's speakerlab K's have side sheets on both sides of one speaker, and one side of the other, so strictly speaking they are in at least partial corners. Quote Link to comment Share on other sites More sharing options...
T.H.E. Droid Posted August 17, 2011 Author Share Posted August 17, 2011 Did you install the jumper from the HF input to the LF input on teh crossover? The crossovers are stock B&K A/4500's which have only one input so I'm not sure what you mean. All of the common rail connections are made to the terminal strips and there are no other jumpers on the board. The stock Klipsch fuse panel and crossover components have been removed and the woofers are direct wired to the crossover. Quote Link to comment Share on other sites More sharing options...
T.H.E. Droid Posted August 17, 2011 Author Share Posted August 17, 2011 It could be that the Ks don't like the high powered Adcom solid state amp. I've had that happen before. Ks like tubes and warm sounding usually lower powered solid state. It's not a hard and fast rule............but pretty close. Do you have another amp to try? Does it sound like the woofers are loose (vibrating in the cabinet) or distorting (bottoming out)? You hardly ever see bass complaints about Khorns on this forum..........it is usually the mid-horn and the tweeters that generate the most complaints if any. Can you post pics of the crossover so we can see how you wired it and the taps being used? I know you know your stuff...........but you really need to be sure about the wiring first. I do have a tube amp I can try. I've never bought the argument that K-horns "like" tubes and low powered equipment. They are so efficient that you should be able to get reasonable levels without a lot of input power, but I suspect the preference for "warm sounding" amplifiers has more to do with equpment with less high frequency response and the Klipsch horn reputation for harsness in the mids and highs. There is no rattling or popping from the woofers, although at this point I'm going to take them out for a thorough inspection because one tweeter was blown when I bought the speakers. I know the stock tweeters are prone to blowing out, but a blown tweeter implies that the speakers may have be overdriven by an underpowered amp so there could be some damage. I have had a chance to isolate each driver with an input speaker and although the bass doesn't sound right, it is capable of chest-thumping output without popping or crackling. I have had woofers with tears and they generally produced a popping sound. Ditto for the mids and tweeters, which all produce strong levels without any snap, crackle or pop. Bob Crites has pictures of his A/4500 crossover on is site, my crossovers look exactly like his photos. I've checked all the wiring to make sure all drivers are properly polarized. Quote Link to comment Share on other sites More sharing options...
T.H.E. Droid Posted August 17, 2011 Author Share Posted August 17, 2011 I did read up on some threads about sealing the tailboards with foam or gaskets, and that raises a simple question? If not making an airtight seal into the back of the corner is causing the speaker to sound really bad, how is it that PWK would allow the speakers to be shipped to customers without such a seal already in place? Quote Link to comment Share on other sites More sharing options...
Ironsave Posted August 17, 2011 Share Posted August 17, 2011 I did read up on some threads about sealing the tailboards with foam or gaskets, and that raises a simple question? If not making an airtight seal into the back of the corner is causing the speaker to sound really bad, how is it that PWK would allow the speakers to be shipped to customers without such a seal already in place? I believe the answer is they were designed to be sealed in corners at the owner's location. I do not know if they need to be "airtight" but there should be no gaps visible. (The airtight thing may be the next progression; IDK). I am no KHorn expert, but I have never heard of them described as you do; without something being wrong with them electrically or mechanically. Good Luck; these guys on this Forum (and Mr. Crites) are the best. Quote Link to comment Share on other sites More sharing options...
fini Posted August 17, 2011 Share Posted August 17, 2011 I did read up on some threads about sealing the tailboards with foam or gaskets, and that raises a simple question? If not making an airtight seal into the back of the corner is causing the speaker to sound really bad, how is it that PWK would allow the speakers to be shipped to customers without such a seal already in place? That won't cause them to sound bad, you just won't get an even bass response. Quote Link to comment Share on other sites More sharing options...
fini Posted August 17, 2011 Share Posted August 17, 2011 One overlooked possibility is that you just don't like them. Not outside the realm... Quote Link to comment Share on other sites More sharing options...
Ironsave Posted August 17, 2011 Share Posted August 17, 2011 One overlooked possibility is that you just don't like them. Not outside the realm... Fini, You could be right; but he loves his Corns and other Klipsch. He is saying these sound worse than 901s for Pete's sake! (I think something, or several somethings are wired wrong). Quote Link to comment Share on other sites More sharing options...
gnatnoop Posted August 17, 2011 Share Posted August 17, 2011 i really would check the wiring from the crossover to the drivers. my K's were delivered and set up by klipsch dealer.....and they were wired incorrectly by the tech. it took all of 10 seconds of listening to know something was not right. Quote Link to comment Share on other sites More sharing options...
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