Khorn K-77 vertical mounting?

[greg928gts]

Is there any reason why I couldn't mount the K-77 tweeter vertically next to the Khorn midrange instead of horizontally above it? I think I've heard from someone that they were originally mounted that way in the early models. What kind of performance difference is there, if any?

Greg

[ZAKO]

Vertical mounting...120 degree dispersion. But You cant exceed 90 degree with out reflecting off the corners (90 degree) so why bother?

[greg928gts]

Sorry, what?

[Daddy Dee]

Yep, the vertical mounting is the manufacturer's recommendation. From my limited observation of Klipsch speakers, I think that the vertical Cornwall may be the only example of this mounting orientation.

I have supposed, but don't actually know, that PWK preferred the horizontal orientation because it's use vertical, and off center, would require the manufacture of a left and right speaker cabinet. This would be somewhat more costly process. Of course, I also suppose that if he thought it made a difference of any significance to improve the product, he would have done it.

[WMcD]

I had posted the polar response plot of the T-35 some time ago. You might be able to find it. It seemed to me like the horizontal and vertical patterns were very close. Not identical though.

It did look like EV considered long side vertical to be their standard. EV speakers and the "Cornwall II" (first time around) used long side vertical. The mid too. Mirror image pairs were sold.

(The original CW had a tall slotted port in the back. Very soon this was changed to the long used front port at the bottom. Someplace along the line the "II" was dropped. Very much later the CW was built using non EV horns and drivers and the "II" came back into use. Perhaps others can comment.)

When the K-Horn had the K-3 midrange horn, PWK used a University tweeter and then the EV T-35 mounted vertically.

Of course then the K-400 horn was introduced. I recall seeing one set up by PWK where the T-35 was horizontal and inside the mouth of the K-400.

I will guess that hornzontal orientation created less of a blockage of the mouth. The T-35 is almost as tall as the mouth and perhaps this caused some hesitation.

There is a school of thought saying that co-axial driver placement is better. There will not be lobeing in the cross over region. OTOH, there is a very, very narrow range where the cross over occurs in the T-35 and K-400. So perhaps this was considered a nice experimental tweek which showed it was not necessary to have a co-axial set up.

It may be that the T-35 works a bit better in a flat baffle. I.e. where there is a board around it. In any event the K-Horn assembly has the T-35 mounted above and center on the K-400.

The SpeakerLab version of the K-Horn used a vertical tweeter at the side of the of the midrange. One tweeter version was supposedly a plastic copy of the T-35. I've never seen this erzatz T-35 though. I believe SpeakerLab did this just to save on wood, or more accurately the MDF they used.

This side positioning may not be so good if lobeing (sp) is an issue. Again there is a very narrow crossover region, so maybe it is not.

Side mounting introduces another issue. Even if the arrangement is to make the placement mirror images, is it best to put the tweeters toward the center, or toward the side.

If you're tweeking, don't forget another possibility. That is putting the tweeter in a box sitting on top of the upper unit so that it is placed, front to back, at the same location as the driver at the back of the K-400 horn.

Does any of these placements do any good. I don't know. I used the standard above the mid in my home made set.

PWK allowed some advocates of tri-amping and active crossovers to demonstrate that very expensive set up. There was no difference to be heard.

There was also an experiment with getting the K-77 driver at the back and using a pipe to bring the sound up to a horn at the front. After some equalization there was no difference.

My understanding is that PWK would indeed entertain tweeking. He wanted the K-Horn to be the best. OTOH he was not about to implement the tweek in production unless there was a real difference.

Now you know what I know.

I say tweeking is fun and may be worth the money in terms of entertainment. But most are not really making the system better . . . just different . . . and probably not too different.

Gil

[greg928gts]

Thanks Gil, for a very nicely thought out and detailed response to my question.

Just bear with me here on this next question, and please don't ask me why I'm asking. O.k.? O.k.. If you're gonna ask why, please don't expect an answer!

On the Khorn, what if the K-77 tweeter was mounted at the top side of the front of the bass bin, mounted vertically? The top edge of the tweeter would be flush with the top of the bass bin and the front edge of the tweeter horn would be flush with the front of the bass bin, and it would be lined up so it was pointed in exactly the same direction as standard mounting. Do you think the difference in sound would be as negligible as the other options you mentioned?

I'd really like to see that polar response you talked about. If it's what I think it is, it shows how the sound travels and is dispersed from the tweeter. For instance, I would be able to tell at 6" out from the front of the tweeter, where to keep any obstructions from interfering with the sound. Is that correct?

Greg

[ZAKO]

McDermott.....K77 upper bandwith 17k? JBL 2404 upper bandwith 21.5? is not better? Just different? HOW ABOUT IMPROVEMENT. That K77 needs to be retired.

[Tony Reed]

Can the average human hear up to 21.5?

Tony

[greg928gts]

Mine certainly can't!

Anyway, I'd like to keep things all Klipsch. I own Klipsch, I'm not going to put a JBL component in them. Maybe I'll own JBL's someday and I can enjoy the JBL sound. Right now, I'm a Klipschophile!

Greg

[ZAKO]

FFFnnnnuuuuuuuufffffffffff What? ..you dont want to improve the sound? Then why did you ask? Klipschophile? SNORT!!!!! Dont wake me up again.

[D-MAN]

Speakerlab NEVER sold a plastic EV T-35 or T-80.

Both were the real EV production models. They were mounted vertically on the model K (the Khorn knock-off).

So if you see a Speakerlab model 6 or 7 or even a K for sale, don't hesitate to pick them up, as the horn tweeters are a verbatim replacement for Klipsch Heritage tweeters.

DM

[JohnA]

The T-35 is called a diffraction tweeter. It has wider dispersion if the long axis is vertical. However, it is only wider below about 6k. Since it is usually crossed over at 4500 to 6k, the difference in dispersion is normally moot.

[cwm]

I never did understand how Speakerlab was able to manufacture and sell the Khorn clones/knockoffs, was there a patent expiry involved or was this done under some sort of licensing arrangement??

[djk]

"McDermott.....K77 upper bandwith 17k? JBL 2404 upper bandwith 21.5? is not better? Just different? HOW ABOUT IMPROVEMENT. That K77 needs to be retired."

I'm with Maron, even if you can only hear 10K the 2404 will sound better.

"Anyway, I'd like to keep things all Klipsch. I own Klipsch, I'm not going to put a JBL component in them. Maybe I'll own JBL's someday and I can enjoy the JBL sound. Right now, I'm a Klipschophile!"

PWK bought whatever was cheap, he didn't make anything. Mids from University, Atlas, Hepner, EV. Tweeters from University, EV, Hepner, even Motorola piezos in one model. Woofers: to numerous to keep track of.

"Speakerlab NEVER sold a plastic EV T-35"

Of course not, they used an EV made plastic horn they called the W4000 in their Klipschorn copy.

"I never did understand how Speakerlab was able to manufacture and sell the Khorn clones/knockoffs, was there a patent expiry involved or was this done under some sort of licensing arrangement??"

Patents are for 17 years.

"The T-35 is called a diffraction tweeter. It has wider dispersion if the long axis is vertical. However, it is only wider below about 6k. Since it is usually crossed over at 4500 to 6k, the difference in dispersion is normally moot."

Absolutely correct.

The reason why the vertical mounted tweeter sounds different has to do with the rear mounting on the 3/4" baffle. The rear mounted tweeter sounds better with the long axis vertical. The flush mounted long axis horizontal sounds better than the rear mounted long axis vertical.

This is why Klipsch goes to the time and trouble to flush mount the tweeter in the current Klipschorn.

[greg928gts]

If the flush mounted long axis horizontal sounds better than the rear mounted long axis vertical, then how does the flush mounted long axis vertical sound?

I guess all the people buying new $7K Khorns should run right out and change those cheap tweeters to JBL's? See, I can be grating too.

Some people on this forum should learn to be nicer people.

Greg

[ZAKO]

Im nice if you feed me. otherwise Im an ankle biter. Now can I go to sleep under the table?

[WMcD]

I looked at the SpeakerLab booklet for building the SpeakerLab-K.

The pictures show what sure looks like the mouth of T-35. Even if it is the McCoy, I myself can't say that there was not a plastic version. Or whether what is in the picture is an EV plastic version.

I do know that the more budget tweeter was well below the intracacy of the T-35. A friend has them and I don't complain.

Regarding mounting in that location. I'd think it is impossible to predict with certainty.

Horns are typically tested with no baffle (free space) or set in an infiite plane baffle (or a big plane) which is called half space. The response curve shows the driver-horn itself without the diffraction effects of nearby discontinuities. Even so the raw data is fairly ragged.

My tests of home made units show a ragged response too. This includes when e.g. the Belle type is sitting on a driveway with no other walls close by.

Please note that the mounting of the tweeter in a K-Horn, LS, or Belle is not in free space or a large plane. The midrange mouth sits below and the top of the cabinet is above. OTOH, there is a good bit of real estate to either side.

Now if you move the tweeter to a corner of the top cabinet you're going to have a different dispursion pattern. My guess is that it will be worse.

I will not get into the debate of "better" tweeters. I'd love to see A-B-X comparisons.

We've had a fair amount of traffic about aiming the horns. One school of thought is that it is best to be looking down the throat so you're on-axis.

That will get you the most treble because the T-35 is narrowing its pattern around on axis as frequency goes up. This assumes some symetry in the baffle.

My "brilliant insight" (these usually don't seem brilliant after 10 minutes of reconsideration) is that we also have to consider reduction of reflections from the walls.

Specifically, we wish to reduce reflections from the walls of the room. Hence it may be equally important to aim things directly away from a corner.

This may account for reported improvements where the horns are not aimed exactly at the sweet spot listening position but are either out in the room or aimed away from nearby walls.

Gil

[formica]

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On 3/9/2004 6:20:44 AM djk wrote:

"I never did understand how Speakerlab was able to manufacture and sell the Khorn clones/knockoffs, was there a patent expiry involved or was this done under some sort of licensing arrangement??"

Patents are for 17 years.

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If i recall correctly, there is a mention to the discontinuation of the licensing agreement to manufacture Klipshorn clones in an edition of Dope From Hope. There are no names / brands mentioned but they mention a concern for the quality of the clones. In my opinion, I doubt quality was the driving factor in the decision.

There were speakers which were influenced but not licensed by the Khorn like the JBL Hartsfield, but they were not clones and definitely didnt lack in quality!!

Rob

[John Warren]

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On 3/9/2004 7:13:08 AM greg928s4 wrote:

I guess all the people buying new $7K Khorns should run right out and change those cheap tweeters to JBL's? See, I can be grating too.

Greg

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That is not the point. if Klipsch charged $20k for a pair of Klipschorns would that change the fact that the tweeter is a "low performer"?

[ZAKO]

It still boggles the mind why a better vouce coil/diaphram wasnt made for the K77/T35 Or why Radian didnt introduce one. (aluminum or titanium or Be)