Klipschorns..... UGH

[T.H.E. Droid]

I went back over to thoroughly check out the speakers and this is what I found:

Serial numbers indicate 1988 manufacture

I removed the L-pads and double checked all the connections. All the drivers are properly phased. I couldn't find any open seals or opening that don't belong in the bass cabs.

I removed the side grilles so I could make sure they were seating properly and reseated the speakers into the corner. I have good solid contact with the backboards on both sides.

I can report that I now have better low bass response. Not a huge change, but hearable. However, that woody resonance (seems around 1000 hz) is still there. On my Carmina Burana recording, this gets to the point where it just overpowers and smothers the other music.

I'm not relistening with my Summits and the same passages have clear, low, clean bass and very good separation of the instruments in the areas where the Khorns crash and burn.

Oddly, my copy of Carmina Burana seems to suffer from some super low frequency rumble that is actually more pronounced with the Summits than the Khorns. The Summits have a ported 15" similar to the Cornwalls, so I suspect this rumble might be right around the port's resonant frequence. On the Khorns, it's much less pronounced.

I guess the next step is to pull the bass drivers and check them thorougly and make sure there isn't a rat nest inside the speaker somewhere. (The cloth slot covers are intact so they're probably clean.)

[mark1101]

Sounds like maybe an EQ might help you to knock back the 1000 hz offending sounds.............or maybe you just don't prefer the sound of Khorns. That's happened before.

When we compared Jubilees to Palladiums...............you could definitely hear the "wood sound" of the Jubilee bass horn by contrast. Some might not like that. I have always listened to Klipsch folded bass horns and am used to that sound. Sounds natural to me. But you have listened to other types of speakers and now brought in the folded wooden horns. Maybe just not your cup of tea.

Sounds like you have done a good job setting up and troubleshooting. They are probably working correctly and doing what they are supposed to.

As far as the seals go, Klipsch provides rubber seals on the backs on either side of the opening. However, people have used 1/2" or 3/4" pipe insulation which takes up much more space and can provide a better seal. Sounds like you have that OK.

I'd connect the tube amp and see how that sounds before you get rid of them. I bet that sounds better than the Adcom.

No offense, but in my experience amps like you are using are exactly why people make the "harshness" comments about Klipsch. High powered mid-fi solid state is definitely not what you want for a Khorn..............unless it is warm sounding (usually vintage s/s)...............or McIntosh. Those work. Again, no offense intended. I do not prefer Adcom.

[davis419b]

When I first began this hobby a few years ago I was into Adcom. The first set of Klipsch speakers were Khorns. I hooked them up to my 5802 which was 300wpc and I did not like the sound. I ended up using the 535 @ 60wpc and it sounded much better. It wasnt long before I was introduced to 70's SS and it was an amaging difference. You must try other amps or receivers before you rule out the Khorns or you will possibly miss out an an outstanding speaker !

[Groomlakearea51]

Being an afficionado of the A/4500 (use them on all three pairs of K'horns, the LaScalas and the Belles), the description sounds like everyone says.... There's sumthin' not right.

Two things I would suggest, first is to re-check the connections, wiring, etc.

• Remove anything else besides the L-pads have installed in BEC's A/4500 "circuit".
• Check again and make sure that the wires from the crossovers to the driver terminals are absolutely in phase. You will need to remove the top section and look at the K-77 to make sure the wires are correctly on the terminals. If they've ever been removed and are now on with clips, they could be "backwards". It is difficult to see the "+" mark on the K-77.
• Same thing with the K-55's, There is usually red "dot" or paint mark on the 55's that is next to the "hot" + terminal.
• Since the K'horns came with AK-2's and someone changed those out for the 4500, you need to pull the bass bin cover and make sure that, first, the K-33 woofer is agains the slot board tightly. There are four screws that screw into "nuts" in that board, and if one or more is loosem it will "leak".
• Check the wiring on the K-33's, make sure + is plus and - is minus going to the terminals on the bin's cover board.
• Replace the old gasket on the bin cover board. Use 1/4" wide speaker gasket tape from partsexpress, etc. make sure there are no gaps whatsoever on the tape. The bin "door" must be airtight for the bin to work properly.
• You can use pipe foam to isolate the rear panel (tailboard) from the wall, but in doing so, there will also now be a gap between the wall and the top section. Several methods of truly sealing the bass bin, using the speaker gasket tape both on the tailboard, and along the flanking edges of the bottom piece of the top section. See: http://forums.klipsch.com/forums/t/109618.aspx

Some other suggestions that also helo get the most out of K'horns.

• Seal the gap between the top section and the bass bin by putting that gasket tape along the outer edge, making sure there are no "gaps". In effect what you are doing is making sure that NO bass gets anywhere than running out along the walls like it's is supposed to do.
• You can.... as the above thread discusses, remove and replace the tailboard with a straight tailboard (requires no "baseboards", or cut a new tailboard for which the lower "cut-outs" are matched to you baseboards.
• You can really seal everything by also adding the piece to the bottom of the bin as shown in that thread.

And... you may want to replace the old K-77 tweeters with Crites CT-125's. The A/4500 crossover is designed to take advantage of the wide freq response of the CT's. If the K-77's are "shot", etc., that will profoundly effect how they sound.

Hope that is of some assistance, and best of luck.

[H]

[seti]

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).

Yup something is F'd up.

[Guest " "]

Room size or lack thereof, and distance into the sweet spot (area of centerline overlap) , and the size of that sweet spot is the most common problem. Basically, the larger the room, the large the sweet spot is, while in the sweet spot, they sound great. Small rooms, listening outside of the sweet spot area, and you know what the sound is like.

[mark1101]

In those situations what I found works very well is ALK extreme slope networks. They allow you more volume and eliminate driver overlap. Basically, they get rid of the "harshness" of the top hat and give the bass bin a chance.

[T.H.E. Droid]

one thing I noticed when testing individual drivers was that I was hearing a lot of the vocal range through the woofer section. This seems far too high a crossover point and I was wondering if the slope in the B&K Sound A/4500 crossovers is too shallow and perhaps set too high. I believe all that was on the crossover board was a single choke for a low pass filter, which means a first-order filter.

I still need to open up the bass cabs and make sure the woofers are 100% OK, and while I'm doing that I might just reconnect one of the klipsch bass filters and compare it with the Crites setup in the other speakers. Given that the bass filters are low pass filters in either case, I can reuse the Klipsch low pass sections with the crites crossovers if that solves the problem.

Also, a previous post recommends using the CT125 tweeters with the A/4500 crossover. The poster must have just skimmed my post because of course that is my setup. I believe if you read what Bob has to say about the original K77m tweeters, trying to use them with his A/4500 crossover would damage them. I do like these tweeters and I agree with Bob Crite's ideas about crossing over the midrange horn at a lower frequency to keep it in it's optimum frequency range, so I hope to find some workaround that allows me to keep the crossovers and tweeters.

[Marvel]

The woofer to mid xover point is 400Hz. You can sometimes hear the bottom part of the male vocal range through the bass cabs. Still, you should hear the majority of the vocals through the mid horn. The tweeter will just ad the high freq. content.

The A/4500 crossovers are excellent, and there should be no reason to get rid of them.

Bruce

[nu2toobs]

Did you say you had the original crossovers? If so, put them back in and compare.

[LarryC]

one thing I noticed when testing individual drivers was that I was hearing a lot of the vocal range through the woofer section. This seems far too high a crossover point

Well, you might expect that with the lower Xover point of 400; go to a piano and play the G above middle C -- that's about 400 Hz! And, even with the bass horn's limited HF propagation, I believe 600 is still audible with at least the AK-4 Xover.

In other words, the bass horn provides well-defined fundamental frequencies of many lower mid-range instruments (male voice, lower strings), and even some bass instrument harmonics. Naturally, everything, especially treble instruments, comes into its own as soon as you add the MR horn and especially the tweeter.

[gagelle]

You might not believe this but some people don't like the sound of particular Klipsch speakers. One reviewer Claimed that the only Klipsch speaker he ever liked was the Epic CF-3 and in his opinion, it was the one of the best speakers ever made.

[artarama]

You might not believe this but some people don't like the sound of particular Klipsch speakers. One reviewer Claimed that the only Klipsch speaker he ever liked was the Epic CF-3 and in his opinion, it was the one of the best speakers ever made.

I personally don't think you could find anyone who honestly did not appreciate the quality of the sound of Khorns that were set up and functioning properly and being driven with the "right" electronics. IMHO

I have hooked up a fair amount of different equipment to mine tube & SS. Some of the equipment can sound pretty bad with the Korns and still sound good with the Cornwalls. The Khorns are very sensitive and revieling and that can certainly be a double edged sword.

Others here know much more about trouble shooting the speakers function, personally I suspect the cross-overs.

The Khorns are simply flawless when everything is working properly. They really help to weed out the weakest link in your system and I will guarentee you the weakest link will never be the Khorns. (At least in any system under six figures)

[T.H.E. Droid]

My next step in zeroing in on this problem is to re-insert the original Klipsh bass low pass filters into the bass driver circuit. To do this, I'll bypass the Crites crossover and tie them into the audio source in parallel with the HF crossover, as is done in the original configuration. I'll just do this on one speaker so I can compare the difference. If I that doesn't resolve it I'll have to tear into the bass cabinets and check the individual drivers.

The only thing that bothers me about this conversation is the speculation that I simply might not like the "sound" of Khorns, or my amplifier is the "wrong type" or things like that.

What I'm hearing is distortion, pure and simple, and a tremendous amount of it. Given the reputation of Khorns, that alone tells me there is something wrong. I also have to reject the tube amplifier argument. Any speaker that needs a tube amplifier to sound acceptible is, in my opinion, a failure and a fraud. I know the khorns are neither, so the problem has to lie elsewhere. Besides, nobody has advanced any technical arguments that discuss real world amplifier coupling issues that would explain what I'm hearing anyway. I'm experienced with horn designs. Remember, my first Klipsch speakers were LaScalas, which as also a fully horn loaded design like the Khorn, and shares the same components except the bass design. I can also compare these with a pair of Speakerlab K's, which are mechanically identical for all practical purposes.

I'll keep investigating until I find the culprit, and let you know what I find out.

[Ironsave]

Droid,

Where are you located?

I am sure there has to be someone nearby who could come over and offer his assistance.

(Not that you are incapable; but someone who has Khorns that are correct might zero in on ths issue much easier).

[T.H.E. Droid]

I'm in Northern Oakland County, north of Detroit. Once I eliminate any mechanical/electrical problems with the speakers, having an experienced Khorn owner drop by would be great.

[mark1101]

I would just like echo the response of the poster who mentions how some amplifiers will make Khorns sound horrible and can still sound good on cornwalls. The whole amplifier choice and the "matching" to Khorns is critical. It's not some engineering theory ........that there is no reason it should not work properly. It is a serious matching game that has a very wide variety of results. Some amps sound good with Khorns, and some sound very bad and are not a match.

I still believe a high powered s/s Adcom is one of the absolute worst choices of amplifiers you could possible choose to use with Khorns. You need a vintage s/s like an old McIntosh rebuild, a tube amp, a PWM chip amp, a modern low power s/s (which will be a crap-shoot), or a brand new Mac (which is probably cost prohibitive)..............if you want those Khorns to sound good. The speakers were designed and optimized well before all the high power s/s stuff came out...........and that combo has never played well with Khorns. This is a well known issue.

I'm thinking you know what you are doing with the connections and audio fundamentals. I just don't believe you have anything hooked up wrong at this point. The modded speakers is a troubleshooting issue though. You could probably come to a conclusion sooner if the speakers were stock.

[Groomlakearea51]

While this may sound stupid.... please forgive me, I mean no ill intent but I am now fascinated/ concerned with what you are seeing. I have three pairs of K'horns, '78's, 79's and 84's, all with A/4500's, and in differently configured rooms; two pairs with Onkyo integrated/HT amps, and one pair with McIntosh amp. All sound almost identical (although each pair has it's own subtle "personality"). I've had many Forum members to my home, and all have said that the A/4500's sound superb. With your situation and observations, I was at a loss, other than the rudimentary/ basic thoughts in my previous post.

I have re-read the thread several times and the only additional things I can think of are:

Do you have or have access to a "spare" integrated amp "laying around"? If so, temporarily swap to that and see if there is a difference; leave all bass, treble, midrange, etc. controls at "0" or flat. If it changes radically for the better, then the issue is in the pre and main settings on the Adcoms.

You may need to send the A/4500's back to Bob to be checked. Is it possible that when inserting the 8/16 ohm resistors in the circuits, that the caps were damaged by the soldering gun? I'm not the best in the soldering department, but when I do caps, I always attach "thermal" clips to the cap leads to keep heat from getting to the insides..

Wiring from crossovers to drivers? Is it new? or did you use the old factory wires. In the 80's they used "monster" cable with a clear coating; one side labeled +++, etc. Sometimes that wiring corrodes (turns green inside the clear covering). If it looks suspicious, remove the clips and cut off about an inch, and reconnect the clips.

The A/4500 also works much better with the K-55V (Atlas PD5VH); On my 1984's, when I yanked the AK crossovers and replaced them with 4500's, I also ended up replacing the K-55M's with the PD5VH's and there was a marked difference in quality of the sound. That "reediness" you describe, went away.

There is a gasket between the midrange driver and the horn; it's inside the threaded "nozzle". Check and see if that gasket is still in there and is still flexible.

When you checked the woofers, were they Klipsch K-33's and not some other brand that looks like the K-33's... Just a thought as I know of an instance of that happening before wherein the new owner said something about weird bass, and did not realize that the woofers were swapped at some point.

The culprit may also be the inside of the bass bin. One of my 84's always drove me crazy... Bass was boomy, and not clear. New caps/crossovers, evrything sealed, etc. and I was at the point of replacing the woofers. Well.... I opend up the bins, removed the woofers and took a very close look at the inside of the bin. Voila, the internal panels showed very small gaps where the panels were joined at the factory. Not much, but you could slide a piece of paper in these "slits". I took woodworker glue and carefully laid in a thick bead on all "seams", and after it dried, repeated it. After re-assembly.... problem gone. Later when I was completely rebuilding the 78's, I did the same "trick" on all seams that I could get to. That, and the straight tailboard, they are impressive in all opinions from Forum guests.

Just some thoughts as I sat and tried to think what I would do if faced with the description you have posted.

Best of luck, and hopefully it's something simple.

[H]

[PrestonTom]

I guess there is a reason that the advice being given is all over the map. This is probably due to how we use words. What I hear the OP syaing is that the problems are dramatic (bass problems and harsh mids). To me that implies the problem is something fundamental and not something "fixed" by tube amps or fancy crossover caps.

For the bass, the fundamental problems could be a woofer bin door that is not sealed, a bass bin that is not tight in the corner. I bad room mode that is being energized when the cabinet is placed in a particular corner, or a woofer that is in the wrong polarity. Or simply a badd woofer or mis-wired crossover. Fortunately, it sounds like the OP is on track to check those possibilities.

However, I might be wrong, and maybe the OP just uses dramatic language for less than dramatic problems.

The mid-range issue is trickier. Since the "fundamental problem" may be one of speaker voicing, and the Klipschorn does have a particular sound in the mids. That can be solved by listening to another, properly working K-Horn. If it is also objectionable, then the K-Horn may simply be the wrong choice.

Perhaps this explains why the advice is all over the map.

In either case, good luck with your pursuit.

[T.H.E. Droid]

The problem is that I'm not hearing any technical explanations as to why khorns should not perform well with any good quality amplifier. I'm not considering the option of spending a lot of money on another amp to get the speakers to sound acceptible. It's easier to simply sell them and shove my Summits into the hole. The Khorns are going to have to improve radically to beat the Summits.

I don't subscribe to all the audio mumbo-jumbo which leads people to spend $5000 on speaker cables, put "special" rocks on their speakers or buy a $100 magic marker and paint the edges of their CD's. Loudspeakers are electromechanical machines, pure and simple, and an amplifier that sounds fine on my JBL Summits/Klipsch Cornwalls/Klipsch Heresys and even Bose 901's should sound just fine with Khorns, especially at moderate listening levels.

As to reverting them to stock, that can be done as part of the troubleshooting process except I only have one original working tweeter. I suppose I should get a replacement diaphragm for the bad one since it's worth more than the cost of the diaphragm if it's working.

I do have a properly rebuilt tube amp that I will try once I eliminate any potential mechanical/electrical issues with the speakers. I was not satisfied with the performance of the amp with my Cornwalls, which simply could not supply enough bass energy at some of the higher listening levels. Perhaps the Khorn's more efficient bass section will make a difference. That would be great, because there's just something about the smell of dust being heated up on tube equipment that jogs memories of my youth. Other than running out of bass steam, I had no argument with the amp's performance, it sounded great.

I really do appreciate all the comments and suggestions but I do want to hold the mumbo jumbo to a minimum and want to hear real world technical arguments when you take radical positions. So far, nobody has given me a single technical argument as to why Khorns should souind better with tube equipment. Traditionally what I've heard is the argument that Khorns are so efficient they can perform very well on lower-powered tube equipment, but that's not the same argument.