D-MAN Posted March 23, 2005 Share Posted March 23, 2005 I ran across a patent that referenced a catenoid horn, but reported that the LEE CATENOID mentioned in "How to Build Speaker Enclosures", Baedmaeiff and Davis, Sams Publishing, 1978 (but not disclosed therein) could not be found. I'm not sure that the patent office even knew it was there, being 1958 and all. That's because the patent was owned by Labratory of Electronic Engineering, Inc. in Mass. (not LEE) as US Pat# 2819772. It's a corner horn that uses a catenoid expansion, a rare animal indeed. These were marketed in the late 50's and evidently went extinct, and I would sure like to hear a couple! Here's the link: USPTO But a word of warning, you have to download some sort of "reader" from the USPTO website in order to view the pictures, which is the best part of course. Otherwise, all you can do is read the text. But anyone interested in horn design NEEDS to get into the patent lookup anyway! DM Quote Link to comment Share on other sites More sharing options...
D-MAN Posted March 23, 2005 Author Share Posted March 23, 2005 oK, i downloaded a copy and hacked it down to size and converted it to a jpeg file, it won't look too good, but it'll give you a clue... DM Quote Link to comment Share on other sites More sharing options...
m00n Posted March 23, 2005 Share Posted March 23, 2005 Don't laugh, but who is Lee Catenoid? Quote Link to comment Share on other sites More sharing options...
D-MAN Posted March 23, 2005 Author Share Posted March 23, 2005 mOOn, is this a trick question? The LEE CATENARY (I previously said CATENOID) is the tradename that the speaker was sold as. I have heard the name, but have never even seen a picture of one before, they evidently were quite obscure. Horn afficianados are the only interested parties, I suppose. Hoped to give somebody besides myself a thrill. ...and it can only be a thrill to bonified, dyed-in-the-wool, hardcore horn-heads, that's for sure! I guess I'm finally one of those, now, because I actually got excited that I'd finally seen one! DM Quote Link to comment Share on other sites More sharing options...
m00n Posted March 23, 2005 Share Posted March 23, 2005 SO my guess is that this design was somewhat of a KHorn knockoff? Quote Link to comment Share on other sites More sharing options...
D-MAN Posted March 23, 2005 Author Share Posted March 23, 2005 No, I wouldn't consider it a knockoff by any stretch, you can't patent a knockoff. It has to be explicitly different or has to be an improvement on something else. The only 2 things that the LEE CATENOID has in common with the Klipschorn is that: 1) they both go in the corner 2) they both are folded horns After that, they are completely separate and unrelated animals. Hence the patent on each. DM Quote Link to comment Share on other sites More sharing options...
m00n Posted March 23, 2005 Share Posted March 23, 2005 Ok... I can see your point. Perhaps knockoff was used a little loosely. What I should have said, was this design inspired by the works and findings of Paul's KHorns. Quote Link to comment Share on other sites More sharing options...
Klewless Posted March 24, 2005 Share Posted March 24, 2005 D-MAN Was the Lee a hyperbolic expansion? If so, it seems to me like an excellent choice for horn loaded sub. Especially with the Klipsch woofer? Quote Link to comment Share on other sites More sharing options...
D-MAN Posted March 24, 2005 Author Share Posted March 24, 2005 John, no, it's a "catenoid" type of horn also called a catenary, I believe. That as far as I can tell is an extreme flare rate, way more than a normal tractrix or an exponential or even a hyperbolic type. I only have read of one other horn that uses this type of expansion, and it is meant to be placed up against a wall, that is, it's not a corner horn like the LEE one shown above. Fact is, two inventors have determined this type of horn to be "better" than others, and because of the low number of references available, I have never heard one. mOOn, I suppose that the design was intended to directly compete with the Klipschorn, and that could explain the corner-horn aspect of the design, but other than that, I don't see much relationship-wise to PWK's bifurcated exponential horns. Of course, if it goes in a corner, its going to be compared to the Khorn. But the inventor (I'm guessing here) probably understood the competion, though. It also was competing against the JBL Hartsfield, another cornerhorn made at the time (which went extinct also). So this design was evidently capable (I'm assuming) of holding its own against the competition, but hearing would be believing. Interestingly, it is abundantly clear to all that it failed to effectively compete with the Klipschorn, but there could be other reasons for this other than performance. In particular, it looks larger to me than the Khorn, so that would be a hard sell, of course. DM Quote Link to comment Share on other sites More sharing options...
D-MAN Posted March 24, 2005 Author Share Posted March 24, 2005 mOOn, one more thing, you may have a point about PWK's teachings... The element that I see is that the LEE is also using a front-loaded horn (i.e. the back chamber is sealed). This is practically a trademark for PWK, he used it in all of his front-loaded designs. So that COULD be a PWK influence, it's hard to say. Since PWK was the earliest patent-holder and was there in the market place first with the most-est, he was certainly going to have an influence on horn designers of the time, I think that's going to be inarguable. The Hartsfield also used a front-loaded approach so was that another PWK-instigated approach? Who knows... It may not really mean anything - just a thought. DM Quote Link to comment Share on other sites More sharing options...
D-MAN Posted March 24, 2005 Author Share Posted March 24, 2005 Here's the 1945 Klipschorn patent drawing for a comparison. Note that the drawings are using a 12" field-coil woofer, not the 15" that we are used to today. But aside from being a little larger the modern Khorn still adheres to the layout in the drawings for the most part. DM Quote Link to comment Share on other sites More sharing options...
Dylanl Posted March 25, 2005 Share Posted March 25, 2005 Do you have any idea of the specs. on that folded horn. I have the book you referenced. Quote Link to comment Share on other sites More sharing options...
Marvel Posted March 25, 2005 Share Posted March 25, 2005 The document indicates a front panel width of 25 inches and height of 36 inches. Marvel Quote Link to comment Share on other sites More sharing options...
D-MAN Posted March 25, 2005 Author Share Posted March 25, 2005 I was thinking that that would have been a 15" driver, but now I'm thinking 12" or less. Also the dimensions are quite intriguing. There is enough room to produce a horn length of over 5 feet, and that could allow an Fc as low (maybe lower) as 40Hz quite nicely, due to the smaller size of the driver and therefore, the throat. I didn't see any reference in the text as to the design Fc, so that remains a question. DM Quote Link to comment Share on other sites More sharing options...
ajsons Posted March 26, 2005 Share Posted March 26, 2005 It uses a University 6200 (12") woofer, JBL P8RX mid and University 4401 tweeter. Dr. Edgar gave me a copy of the enclosure plans years ago. Here's the first page. Quote Link to comment Share on other sites More sharing options...
djk Posted March 26, 2005 Share Posted March 26, 2005 CATENOID is misleading, nothing in there resembles one. A catenary is simlar to a parabolic horn, the worst type for LF response. The first taper off the woofer looks catenary. http://www.3d-meier.de/tut3/Seite23.html Quote Link to comment Share on other sites More sharing options...
D-MAN Posted March 29, 2005 Author Share Posted March 29, 2005 Here's my take on it, I hacked the catenoid model described in the previous reference to better describe my interpretation of the LEE design. If in fact a true catenary expansion demands that the throat be the same relative size as the mouth, then the LEE is not a true catenoid horn, of course. The question remains, why would somebody bother to patent a known "bad" design? That is not to say that there are no useless patents, but regardless, it costs quite a bit of money to do so... DM Quote Link to comment Share on other sites More sharing options...
ajsons Posted February 5, 2006 Share Posted February 5, 2006 Drivers. Quote Link to comment Share on other sites More sharing options...
ajsons Posted February 5, 2006 Share Posted February 5, 2006 The rest of the sheets were in bad shape, so I redrew them by hand and dimensioned the pieces based on what were readable. Quote Link to comment Share on other sites More sharing options...
ajsons Posted February 5, 2006 Share Posted February 5, 2006 (Don't trust these dimensions). Quote Link to comment Share on other sites More sharing options...
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