cc1091 Posted July 18, 2001 Share Posted July 18, 2001 I have heard Cornwall speakers and regretted that at the time that I bought my Heresys, that I could not afford a pair of Cornwalls. The Cornwalls that I had heard were from around 1982, and had the horizontal squawker. Since I have started visiting this board, I have read of the older model of Cornwall that had a vertical squawker horn. My question is: was the horn shaped differently in the two models of the Cornwall speaker, or were they essentially the same horn. If anyone has a picture of the two different horns (if there are indeed any differences) it would be appreciated. just curious. Thanks again. Quote Link to comment Share on other sites More sharing options...
Dan-OH!~ Posted July 20, 2001 Share Posted July 20, 2001 They used the same drivers and horns, their orientation and placement is the only difference...., I'm going to have to see about getting some images of my oldie II's one of these times and post them... the orig. cane grills have at least by become, see through enough, that you could easily distinguish the spkr placement. The I's and later II's have the horns mounted horiz. and on centerline of the cabinet (inline with and directly above the Woofer). The old time, (special order) II's have the Woofer offset to one side (but at appr. the same hieght), while both the Squawker & Tweeter Horns are rotated 90 deg. and offset to the opp. side of the woofer (and to my eye and perception, are mounted slightly higher). They were made in matched "Mirrored" pairs..... I most certainly LOVE the sound from mine...., but they ARE needing an estetic upgrade... Dan-OH!~ Quote Link to comment Share on other sites More sharing options...
cc1091 Posted July 20, 2001 Author Share Posted July 20, 2001 Thanks Dan-OH!~ The next logical question is: Is the sound with the vertical squawker overly directional, or does it disperse adequetely so that the "sweet spot" is spread over an area as wide as with a normal (horizontal horn) Cornwall. Yes I have ideas cookin' for a mod to a non-Cornwall (don't fret, everything except money & time spent will be reversable if things don't work out as well as planned). Back to the lab... Quote Link to comment Share on other sites More sharing options...
cc1091 Posted July 20, 2001 Author Share Posted July 20, 2001 Oh yeah... Same drivers and horns...same crossover too?? Thanks again in advance Quote Link to comment Share on other sites More sharing options...
Ray Garrison Posted July 20, 2001 Share Posted July 20, 2001 cc1091, Actually, while this may seem counterintuitive, the way the horn works the dispersion is BETTER in the direction of the SMALLER axis. That is, if you orient a squawker horn so that it is mounted with an up and down, rather than left to right, long axis, you will get BETTER horizontal dispersion and NARROWER vertical dispersion. That's why the earlier horns were made this way - it works better. This is not a night and day difference, mind you, but there is an improvements. However, when you do this, you have to make the speakers in mirror image pairs, which increases the manufacturing costs significantly, and they, uh, look weird. Ray ------------------ Music is art Audio is engineering Quote Link to comment Share on other sites More sharing options...
cc1091 Posted July 21, 2001 Author Share Posted July 21, 2001 Yes that does seem counterintuitive. I'll have to think about that one for a while. Fortunately the part about the difference between the two not being great is the part I really wanted to hear. Now I need to go back to the lab, dismount the squawkers from my Heresys, make some minor modifications to the crossover and do some listening tests before I really dig into my project.. Thanks for the help. Anyone else who has a comment about this issue, please leave it here. I'll be checking back again before I have my first final design, and certainly before I build anything significant. (hmm..does anyone have a shop I can use??) Quote Link to comment Share on other sites More sharing options...
Klipschguy Posted July 21, 2001 Share Posted July 21, 2001 Greetings Klipsch fans, I've been reading about the horn dispersion pattern being "counterintuitive" a number of times on this board, but I'm not convinced. When you look at manufactures' horn lense dispersion characteristics, they ALL give the wide dispersion spec to the widest part of the mouth, and conversely, the narrow spec to the narrow, i.e. the JBL 2382A horn lense gives a 120 degrees x 40 degree dispersion with the 120 from the widest part. The specs hold true across the board for bi-radial, exponential, and diffraction horn lenses from a bunch of manufacturers. The only exception I could think of is possibly an exponential tweeter functioning as a diffraction horn above a certain frequency that one might follow "the counterintuitive" rule, but again I'm not convinced. Anyway, just an observation, and I'm certainly no expert in horn dispersion characteristics. If anyone else wants to chime in, please do so. Regards, KG This message has been edited by Klipschguy on 07-21-2001 at 07:34 AM Quote Link to comment Share on other sites More sharing options...
jdm56 Posted July 21, 2001 Share Posted July 21, 2001 Chiming away! Counterintuitive? I'd say so. I thought that was what the "controlled dispersion" was all about - limiting vertical dispersion to minimize floor and ceiling reflections, while achieving broad enough dispersion in the horizontal plane to effect good coverage in the listening area, yet minimize side wall relections (with proper toe-in). I thought these goals were achieved by the horizontal orientation of the horns. ------------------ JDMcCall Quote Link to comment Share on other sites More sharing options...
Klipschguy Posted July 21, 2001 Share Posted July 21, 2001 Greetings JD, That's the "intuitive" position! Wide mouth = wider dispersion, narrow mouth = narrower dispersion. When I say "wide dispersion" I mean the wider of the contolled dispersion specification of the horn lense, i.e. the 120 degree spec verses the 40 degree spec. I think we're in agreement and saying the same thing. KG Quote Link to comment Share on other sites More sharing options...
TBrennan Posted July 21, 2001 Share Posted July 21, 2001 Klipschguy--Well no, not all horn specs relate wide dispersion to the wide axis. The EV 8HD was a popular 800hz diffraction horn that had it's widest dispersion from the narrow axis. Compare a K-600 to an 8HD, very similar. Quote Link to comment Share on other sites More sharing options...
Klipschguy Posted July 21, 2001 Share Posted July 21, 2001 Huh...That's interesting. Intuitively, it doesn't seem that a Klipsch exponential horn would differ from a JBL exponential (or any other manufacturer) in their fundamental dispersion characteristics, i.e. the widest part of the horn gives the widest dispersion in a JBL, so it should in a Klipsch (I understand they will have different flare rates, etc). Any acoustic engineers have any enlightenment on this subject? Please try to make explanations jibe with properties of physics. I don't doubt the info, but as a man of science, I need to understand and the numbers must add up. None of this "Atlas used a magic elixer" stuff. LOL. KG This message has been edited by Klipschguy on 07-21-2001 at 08:23 PM Quote Link to comment Share on other sites More sharing options...
djk Posted July 21, 2001 Share Posted July 21, 2001 It is easier to examine straight sided horn behavior so I will do it first. A horn with its sidewall set at 90* will be 90* as long as the wavelengths are reasonable.An example would be the Klipsch K5J,Altec 511,JBL 2350, all 30" wide straight sided 90* horns.They will all be 90* in the horizonal plane down to about 370hz.Below there they will start to open up.At a half oct above the 370hz point, or about 500hz, they will narrow to about 60* due to mouth reflecions.Above about 700hz they will be back to 90* again and hold this all the way up to the throat opening size.A 1" neck in the throat will cause it to narrow above about 11Khz.This is why the newer horns pinch down to about 1/2", to get the horizontal dispersion up there. Obviously if we are making a three way speaker this is of little concern. Actually this narrow pinch sounds bad at high volume levels and is a real problem with these type of horns.The sound takes on a "quacking" or "frying bacon" quality that is quite unpleasant.In the vertical plane these straight sided, or radial type horns, have a dispersion angle that is again a function of the size and wavelengths involved.These horns are advertised as being 40* vertically. At what frequencies are they even close to this? With a 10" height dimension they will be 40* in the octave centered at about 2.5Khz.Below this they will open up to 180* as defined by the baffle board of the speaker box and then open up again as the wavelengths become longer than this dimension.So in the 1Khz oct they will be about 90* and at 500hz about 180* .The 36" height of a Cornwall type speaker front will keep the vertical dispersion to about 180* down to about 200hz.If the horn is on the top of the box like an Altec Model 19 or a Klipschorn there won't be as much low frequency loading.Above 5Khz the dispersion continues to narrow and the 1" or so dimension gives 20~40* dispersion in the top octave. Those little "vanes" on the K77/T35 horn are meant to act like a smaller horn at high frequency and are only partially effective.The older version had a much narrower horn.The old Klipsch price sheets show the "rotated" horn version of the Cornwall as being intended for "Lowboy" use, ie: with the 36" dimension in the horizontal plane.While I do think these horns do sound better with the long axis in the vertical plane, I must point out that they also sound best with their center axis in a vertical line with the other drivers.I have built many of such and the tall tower look goes well with big screen televisions. Quote Link to comment Share on other sites More sharing options...
cc1091 Posted July 22, 2001 Author Share Posted July 22, 2001 djk- I wish I understood physics as well as you. I think what your telling me is that: 1. The horn experiences many different types of reflections and diffractions before it leaves the horn and enters the environment of your local room, and 2. The horn also has functional characteristics that are based upon the box in which it is housed. and 3. axial alignment becomes important as you limit the horizontal dispersion of the driver (another Klipsch fan sent me a pic from ebay that also shows the tweeter of the older Cornwall in a vertical alignment next to the vertical squawker, which I was not aware of). I may have to look you up when I'm back in CR visiting the parents. Quote Link to comment Share on other sites More sharing options...
Klipschguy Posted July 22, 2001 Share Posted July 22, 2001 DJK, Thanks for the explanation. So it seems that a horn works intuitively at certain frequencies (the ones towards the middle of the horns' own response curve), and then widens as frequency drops (wavelengths are longer), and then narrows as frequency increases (wavelengths are shorter). The baffle also having an effect on dispersion. From reading your explanation, it also appears quite important to operate the horns within a certain bandwidth to avoid various types of bad sound: honking, sizzle, poor dispersion, etc. Also, I found it interesting that some of the old Cornwalls were meant to be used on their sides (lowboy). Warm regards, KG Quote Link to comment Share on other sites More sharing options...
Dan-OH!~ Posted July 23, 2001 Share Posted July 23, 2001 going back through this thread..., and catching up on some responces ... cc1091 - back to the question of common components.., it would appear that the only component that's diff. between the orig. Cornwall, and "old" II's would be the "motor-board" (love that term for it, must be of Brit origin)..., the panel which the spkr's are mounted to. all other components including the crossover are the same.... Ray - that "wierd" look, must be one of those "eye of the beholder" things..., to me they look logical. Speakers having to look just alike (rather than mirror images of each other), must be a product of conditioning. On another note, After reading one of your other posts a while back....., I tried swapping my mirrored II's around, so that the Horns were inbound (as you had stated something about that being the rec. positioning) and found that, at least in my listening room, to my ears....., I went from having FANTASTIC (your setting in the same room with the artist.....) "Imaging", to nearly none (it was much more like you were just listening to a couple of stereo spkr's in a room....). Thus I pulled the 2 wheeled hand truck, back into the house, and swapped 'em back to Horn's outbound (don't like to drag those metal feet across our tile floor...., and I sure don't lift these without some form of assistance....). djk - it would seem to me, to be a bit of a stretch, to say that early Cornwall II's were "intended" for Lowboy usage. They did offer them in either version (although as I recall, the Cornwall II was the only Klipsch with this Lowboy offering). I believe I saw that same literature on ebay and the Lowboy was shown to the right of the std. upright model (infering to me, that it was another option). I would assume that these Lowboy's may have been preffered in some theater or auditorium type applications. I can't imagine that it was a very popular home item. I've been searching the web a little, to see if I could find the spec.s including dispersion patterns for these horns, but I haven't had any luck finding that level of detail...., does anyone else have such in "soft" form??? Dan-OH!~ Quote Link to comment Share on other sites More sharing options...
Klewless Posted July 24, 2001 Share Posted July 24, 2001 Low Boy speakers, If you look into older books on hi-fi you'll find that many speakers were of this design. People bought furniture first and speakers second. I remember some of them as a youngster and they sounded as good as the upright style. It all depends on the room, etc. Low Boy where the width is greater than the height have a bigger footprint and probably look better in a big wide room. Times have changed and many people seem to prefer narrow towers and little boxes for speakers today. With today's five to seven speaker systems footprint is a big issue. This probably accounts (in addition to cost) for the declining sales of the large heritage speakers. It seems to me that when it comes to uncompressed and natural bass, nothing comes close to big speakers. Just my 2 cents ..... ------------------ John P St Paul, MN Quote Link to comment Share on other sites More sharing options...
Shock-Late Posted July 24, 2001 Share Posted July 24, 2001 Well, maybe I'm completely wrong, but i would say that the "vertical-mounted" mid and high horns, as well as the mirror-imaged construction, were made for an "horizontal" placing of the cornwalls, as you can see with some studio monitors...the mids being then in their logical horizontal dispersion... Frans Quote Link to comment Share on other sites More sharing options...
Shock-Late Posted July 24, 2001 Share Posted July 24, 2001 Well, maybe I'm completely wrong, but i would say that the "vertical-mounted" mid and high horns, as well as the mirror-imaged construction, were made for an "horizontal" placing of the cornwalls, as you can see with some studio monitors...the mids being then in their logical horizontal dispersion... Frans Quote Link to comment Share on other sites More sharing options...
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