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Horn-Loaded Speakers
Topic: Why I do not like La-horns. The tomatoes…

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Posted by Romy the Cat on 05-02-2011

The Jean-Michel Le Cléac'h’s horns or as I call them La-Horns get a lot of popularity among people who are trying to build horns loaded systems. But as anything else in audio the Morons hear any noise and they has no idea how to associate the noise with anything else, so, instead of sensibly deal with noise they just brainlessly mimic what they do not understand.

The Jean-Michel enthusiasm about the subject is appealing but only to degree. If one have objectives to endless chewing over of the same irrelevant things then Mr. Cléac'h’s view are good playground for it. It similar if you like tomatoes. You love them and you feel that   tomatoes salad is something that you can’t live without them. You decided to grow your own tomatoes and to do so you but, seeds, cultivate seeding lend, buy a tractor, fertilizers, fight with animals and insects, so do who any other tomato-grower would do. What is very important is to understand that you go over all of your agrarian waves because you want to have better tomatoes. In contrary you might get hooked with a perfect geometry and perfect angle of the spikes of your plow. For the next 15 year you are obsessed with angle of the “perfect spike” and behind your new hobby no one, even you, see the smell and taste of tomatoes.

The reason I write this note is an email that I got last night from a person who is trying to build a big horn system and he asked if I suggest him to buy La-horns.  He said that he read all that I expressed about the subject but he still does not get to home believe: to me or to Jean-Michel. I was surprised with shaping of the question like this as I do not see any conflict or rivalry between Jean-Michel and myself. The difference between Jean-Michel and me is in our approach. Jean-Michel approaches subjects of horns as a self-contained entity. He is way more intelligent, educated and much more scientifically minded then me. He is able to dissect the horn theory to the level that I not able to understand. This is fact. Also, it is a fact that I do not find 95% of what Jean-Michel says a relevant to anything that I value in audio. It is not that he is incorrect, in fact I feel that he is very accurate but it is all about a “perfect spike” that has no, or very little relation to the final Sound of Tomato. If we doctors then my view of horns is a health of enter body. A doctor Le Cléac'h look like think that developing the best method to test some kind of Bilirubin in blood is a way of practicing the healthy well-being. It is not that I find that Bilirubin testing is not important but I do find that from a perspective of general medicine it is pretty much irrelevant subject.

I never read Jean-Michel’s view of playback, audio, sound of music at that mater. I am sure they exist but he does not find it worth to expose at least. Without it I have no reference and no context of many of Jean-Michel’s commentaries.  Why for instance I feel that Jean-Michel’s view about playback organization I find are important? Because the La-horn profile in many ways conflict with ideas of about playback organization. Look at the picture.


You see the La-horn profile with two points A and B. From the throat of the horn to the point A the La-horn implements a tractrix profile. Then there is a section from points A to point B that I call “negative opening”.  This negative opening adds SIGNIFICANTLY to the diameter of the horn. Do I consider that negative opening is beneficial for sound? Yes, I do. At HF it is beneficial, event though I did see the idiots make upperbass La-horns. Why in such case I am not convinced that for MF the La-horn is preferable? Because the sonic practical benefit that might or might not come from the La-horn negative opening are in my view well offset by the system design compromisers that negative opening force you to endure. When idiots stick Yellow Drivers in 150Hz La-horn and use it as full-range channels then I do not talk about negative opening advantages/disadvantages as this setup is idiotic anyhow. In context of multichannel installation   I would only think about the La-profile disadvantage. It might be different if somebody would think about the whole acoustic system setup with La-horn employed. However, no one does it. Jean-Michel draw endless recommendations for big La-profile with ported bass driver at the bottom and the folks who sell La-profiles juts sell individual horns. I did not see the La-profile to be tested and challenged at any installation that I would find offensive or interesting.

It would be a good idea for somebody to try come up with a 5-6 channels when the channels atop would have max La-horn negative opening and gradually to decries the negative opening as the frequency goes down. To make all of it work sonically, make the frame and horn arrangement that it would look attractively would be a very interesting and challenging task. I think this is what Jean-Michel need to do in order to get any credibility for his La-horn profile. Until I see this attempt is undertaken I would insist that I see no deferens between Tractrix and La-horn but find that Tractrix has a lot of real-estate advantages.

Rgs, Romy the Cat

Posted by Romy the Cat on 05-15-2011

Here is a good illustration for people who do not get it why La-profile is suck a damn idea with lower then MF channels. There is a guy in AU who makes the La-profile horns from some kind of plasmas and sell horns separately, not organized into complete installations.  The people buy into it and here is what they have:

Pay attention that the upper-bass horn in this installation has in that room and in those frequencies absolutely no benefit from La-horn negative opening. In fact the negative opening act as HUGE impediment as it waste a lot of very needed in this configuration vertical and horizontal space.  The owner is not expressed person in the subject and he apparently followed the advice or instance of the horn maker. There is nothing wrong in negative opening but it not suppose to be brainless  demagogy the has no relativity to practicality. Read my notes in the provided link and you will get the idea why.

Rgs, Romy the Cat

Posted by T3GGG on 05-16-2011
Romy, what is your thought on using a Tractrix flare on a Midbass horn, Fc 140HZ then maybe a Le Cleah horn above, say 400hz. To me this looks on paper to be the best of both worlds and avoids the 1metre plus midbass Le Cleac'h horn.

I am putting together a set up such as this ATM.

Posted by Romy the Cat on 05-16-2011
 T3GGG wrote:
Romy, what is your thought on using a Tractrix flare on a Midbass horn, Fc 140HZ then maybe a Le Cleah horn above, say 400hz. To me this looks on paper to be the best of both worlds and avoids the 1metre plus midbass Le Cleac'h horn.

I am putting together a set up such as this ATM.
Yes, to use no negative opening at midbass is always a good idea as La-profile is wordless at Midbass. You might run La-profile at your 400Hz midrange but you still will have 30% of space wasted for negative opening. At high frequency the negative opening is a good thing but here is what no one will ask you – how much practical benefit the negative opening will server and how much will it be compromised that your MF channel become much larger then it has to be? No one would answer this question and I am VERY convinced that it if you put Mr. Le Cleac'h himself and let him blindly to hear his La-profile form and Tractrix with the same driver then it will not be much difference. The La-profile is Tractrix + negative opening; it does work better at HF if you use only one driver but, in my view, if you a combination of multiple drivers per channel then La-profile become an impediment. Do not forget that it is not only you MF will be larger – you can overlap the negative opening of your La-profiles (which is very good). You tweeter, if you use it will be much further from you MF and much higher in your setup. If in case the Midbass/MF intersection you can overlap the negative opening of the neighboring horn then you can’t do it with tweeters as tweeters will be behind the MF to keep time alignment.

So, the point that I keep making is that whatever Mr. Le Cleac'h pitchers lock holistic vision of multichannel system. If a person use a single “full-range”  horn with yellow driver and W bass bin at the bottom then La-profile is fine, I think this is how Le Cleac'h  started advocate the advantage of the La-profiles. However, in context of multichannel in my view the advantages of La-profile are questionable.

What I call for is not listen Le Cleac'h or me but to make doings, circulate the space and distance and make you own judgment. You need to do a LOT of sketches (hand or by a commuter) and a lot of planning. We all have more or less the same rule – the main souses of MF/HF must be more or less at ears level or a very slightly higher. If you have your upperbass horn (140HZ is upperbass NOT midbass horn) sitting UNDER the MF then all your results are very predictable and conventional.

So, do you own planning. Rooms are different, the way how people ingrate playback into rooms are different. Take everything in consideration, not only some absentminded ideas that this of that is better.  It has to be practical better in context of your specific application and your specific configuration. But to get there you need to do pre-build planning of the entire acoustic system, not just one horn…

The Cat

Posted by Romy the Cat on 05-16-2011

Jean-Michel posted a reply in response to my commentary:

 Jean-Michel Le Cléac'h wrote:


Romy is totally wrong on that.

( a parte: I hypothesize that Romy's sentence: "why I don't not like Le Cléac'h (La) horns " doesn't find it's origin in any theorical nor technical consideration... please note that one of Romy's reproach against me is that, in his not humble opinion, I don't share enough my own philosophical considerations about what a good sound should be nor I share enough my own ideas about the proper setting up of a complete audio system... )

At high frequency, the waves takes off from the wall of the horn at a shorter distance from the throat than for the lower frequencies, therefore, at HF the roll-back mouth has no effect.

At low frequency, the wavefronts leaves the wall of the horn at a large distance from the throat. with an unbaffled tractrix horn this means that the low frequency waves will be partly reflected at the edge of the mouth.

Give a look to:

You can see the effect of the reflected waves on the half upper part of the polar graph corresponding to a truncated Le Cléac'h horn.

Then, you can see in the lower half of the graph the increased smoothness of the polar graph of the "complete roll-back" Le Cléac'h horn .

Then there is the problem of the integration with the bass channel and with the highs. I don't think that the eventual integration problems associated with the increased diameter of the Le Cleac'h horn are of the same importance level than the benefits of the reduction of the reflected and diffracted waves at the mouth.

Best regards from Paris, France

Jean-Michel Le Cléac'h

Of cause I very much disagree with his concussions. If we accept the Jean-Michel’s assumption that anything beside pressure travels(!) physically across a horn then frequency while they take off from the walls of the horn obey the rules of diffraction - or  bending themselves to the region of geometrical shadow. At HF the bending is “too violent” as the HF slide of the age of the horn, here is what the La-profile works very good providing a smooth transition to decaying HF. BTW, if you look at the shape of my “Water Drop” tweeter then it will be the same La-Profile with negative opening only extended at full 190 degree. BTW, the constant directivity horns are built in the very same way, introducing diffraction edges and they work only at HF.

At LF the wavelength becomes too long and the negative opening not even being recognized. From my photography time I remember that diffraction increases as the diameter of boundary approaches the wavelength. For 2000kH-3000kH and the wavelength of 4 -6 inches the extra 2-4” of La-profile negative opening is working fine. But at 100Hz and wavelength of 135 inch the 2-4” of La-profile negative opening are negligible. You do not need to have special knowledge but just a common sense to understand that as frequency drops the effectiveness of the La-profile negative opening drops as well. BTW as 40Hz and with much more longer wavelength the edge of the horn has no difference at all…

Sure, in response to it the scientific-minded Jean-Michel posts the graph that demonstrates that La-profile at LF has “increased smoothness of the polar graph”. Well, what Jean-Michel forgets however that at LF is not negative opening of his La-profile begin to work but the fact the he has larger baffle around his horn/ If you remember in 30s WE, Klangfilm and other did the same by increasing the forward LF output and smoothing the of-axis response by building small open baffles around the horn mouth.  There is nothing wrong with that approach (for LF only) but you pay by using larger mouths per each channels, larger then it is necessary for given cut off rate.

So, to have a graph is one thing but to interpret the true applied meaning of the graph is a bit other thing. A mouth of horn does act at LF baffle. So, if one wants to do the comparative graph then the max diameters of Tartaric and La-profile hors need to be identical.  I hope everyone understand that it happens then La-profile will have a good half-octave less in profile rate.

Now is the elephant in the room: “I don't think that the eventual integration problems associated with the increased diameter of the Le Cleac'h horn are of the same importance level than the benefits of the reduction of the reflected and diffracted waves at the mouth.” The integration problems associated with the increased diameter is a HUGE problem, really HUGE and if Mr. Le Cléac'h do not spend time to collect graphs, build theories but play with practically of playback then he would not deny it.  The reduction of the reflected and diffracted waves at the mouth is good but in my estimation it is way less important, not to mention that it work ONLY at HF. I personally feel that randomizing mouth edge is way more effective then negative opening and it takes no extra toll of the size of individual channel.

In the end I do not accuse Jean-Michel that he “I don't share enough his own philosophical considerations about what a good sound should be nor I share enough my own ideas about the proper setting up of a complete audio system”. I do point out the fact that whatever Jean-Michel express has absolutely completed view about audio system. Jean-Michel dissects a frog, sees some bones inside and claims that since human and frogs have bones then we are all the same species. Well, it is a bit more complex then that…, but at the same time it is much simpler if to use the Oakum's Razor burden of proof …

Rgs, Romy the Cat

Posted by Corallus on 12-28-2013

Posted by Romy the Cat on 12-29-2013
Very sad news. I never meat him and we never listened anything together but I did read a lot of his internet posts and his thinking. Jean Michel was for sure in many ways data-only oriented person, it is the domain where I do not particularly strong or caring. Nevertheless, he was for sure a great horn theorists and horn universe did lose a lot of weight with Jean Michel’s departure. Well, we all will be there… My condolences to Jean Michel’s family and to all community of French audio folks who was close to Jean Michel.

Posted by Romy the Cat on 01-22-2016
Jean-Michel Le Cléac'h is RIP and it is not a good idea to talk bad about dead people. However, it is not a personal commentary against Jean-Michel but rather my attempt to point out a huge harm that he did with his idea of what I call La-horns or the Jean-Michel profile. The irony is that Jean-Michel was not wrong advocating negative opening of La-horns. However, his teaching land on the shoulder of many foolish audio morons who read silent white papers and converted everything, even own toilets into La-profiles. The last was the retard From Moscow who insist that even his stupid midbass horns has to be Le Cléac'h 
The reality is very different. Jean-Michel was a wonderful and dedicated to horn subject man and he was what I call theoretic. He did not build any practical installations and according to the people who knew him personally he did not particularly care or like to listen the things. So, conceptually, Le Cléac'h horn are the best possible horns and all empirical data clearly proves it. Then we enter a more murky territory. Get two identical 500-7000 drivers and load them in identical Tratrix and La-horns. I would estimate that no more than 1 % of listeners would recognize any practical difference. If we are taking about 2000-12000 range then the percentage people who would prefer La-horns would grow to 30-40%. However, there is a “kink” in that. Take 4 horns: 2 Tratrix and two La-horns, lower and upper MF and do the same experiment. Now the advantages of La-horns will be gone, moreover anybody with brain and ear would prefer Tratrix and it will be not because Tratrix are better profile but because in case of multichannel and time aligned systems they are better integrateable. Take a look at the image below and pretend that we are losing the integration waste with each of 4-5 channels and end up not with acoustic system of 6 feet but rather 8 feet. Further drivers more lobbing, more intermodulations problems, more comb filtration, more narrow listening position, more timing problem. All of it very much offsets the general advantage of Le Cléac'h profile, the advantage that is very questionably practically benefit you… even with one horn. There is many way to deal with edge of Tratrix profile and do not give up to the unpractical French theories.


BTW, here is good example of very smart and thoughtful use of Tratrix. “Komodo” employed within playback the La-Horn. 
The large horn are Tratrix, then his has upper MF horn, 4500hz to 9000hz, the horn where excessive Le Cléac'h opening would not affect anything negatively as he “lost” probably  no more than 1”.  I am not a big advocate to use upper and lower MF driver, I prefer the whole MF to be cared by one driver but for what Komodo wanted the use of LaHorn at upper MF is perfectly justifiable.

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