be wrote:

I know they knew a lot in those days and could have dealt with the nonlinearity of air if they wished to or if there attention was drawn to it.

Actually, you are right. The problem during those days was not with shortage of knowledge but with absent of needs to do better then they did.

be wrote:

Actually air is nonlinear with a uneven order nonlinear connection between pressure and volumen by audio frequencies at least. An uneven order nonlinearity produces even order distortions, this might explain our preference for single ended devices, that predominantly produces distortion of the same nature as air. Our brain have due to natural selection been optimised, with ease, to filter out excactly the kind of distortions that dominates the medium that we are in: Air. It would be to our disadvantage if we just by being, would get a headache due to the overload of our signal processing device between our ears.

I understand it very well, but you also have to take under consideration that no one even approach to construct of driver-horn as Sound source but they rather treat it as a pressure transducing system.

be wrote:

More down to normal engineering: Manufacturers of compression drivers have in the "recent" years introduced drivers with short throats and larger flare rates to measurebly minimize the amount of produced distortion that stems from airs pressure nonlinearity.

Yes, I know about it, but at the same they a lot of other “inventions” that do not work out… Anyhow, Erick, let keep this thread dedicated to Jessie’s project.

While not qualified to comment on the subject at this depth, I am very much following the discussion, and though it may seem slightly "off-thread", it does not go unappreciated. A technical understanding is necessary and I am always trying to learn more...

That said, I tend to agree with Romy’s statement:

"...It is my believe that NO one TRULY knows what the hell it going on with horns and no one has any idea how a driver will sound when it will be horn loaded..."

While I am wary of those who speak with absolute certainty on subjects like the genesis of man, life after death, and to some extent, horns, horns are something we might one day understand. Just how much of this might be helpful is another question.

The grace with which one descends a flight of stairs does not depend on his ability to consciously solve in real-time the pages of logarithmic (?) equations describing his movements.


jd*

jessie.dazzle wrote:

A technical understanding is necessary and I am always trying to learn more...

Romy,

Thanks for the thoughtful writing... Sorry my response is not exactly "time-aligned"... I've been meaning to reply for the past few days, but my other life has been in the way...

Romy's quotes in blue :

In  a few month, after you installed your 6-chenals, power it -  is the most interesting, the most complex and the most thrilling things will take place – you would need from an array of “frequencies pushing channels” to teach your acoustic system to play sound PROPERLY.

This is a moment I have been anticipating for a long time, and will address it as sincerely as possible; taking no shortcuts... It is the reason I designed so much versatility into the horn locating frame and into the horn making process.

Unfortunately this step, the most important step among all, is not just undermined by the Morons out there but even the discussing the methods that might be used to do so is a semi-banned subject among the most audio people.

Yes... Things might be different if there were a manufacturer that squarely addressed these issues while at the same time educating his elected communicators (his distributors and the press), and then built a comprehensive data base (a web address) that skillfully educated potentially interested customers in terms they could easily grasp. This may in fact already exist, but if so, it is the super-rare exception.

That all might eventually bring you to a very complex question: how you would like Sound to be…. and ultimately it might lead you to the biggest subject of the entire audio: who we are. It might take a year or two to learn experiencing and reacting to the needs and capacity of your “6-chennals”. During that time the evolution of your “6-chennals” will follow the substance of your personality and depth of your musical/sonic interests.

I believe that any serious audio installation will absolutely reflect the character of the user.

What would be the most interesting is that you might discover that you do not need to know a lot of technical things in order to “know” them. Some purely technical aspects will become an organic extension of your sonic interests.

Instinct and intuition are my main tools. Developing them (and my confidence in them) is the result of their continued use. Both are in fact based on technical experience and the ability to project and extrapolate from it and from that of other domains.

Do not be surprised if at that time you might loose any interest to a cookie-cutter audio industry’s offering.

Well this weekend a buyer came for the speakers of my previous life. I had kept them until now as a reference. I have owned them for eight years in 4 locations; I know their performance very well... They have been one of few audio devices that I would consider educational in a long-term sense. I would not have sold them so early if they had not been so clearly dwarfed by the indicated potential of this project.

You might feel then that if a person does not practice his own “tailored sound” (and it has NOTHING to do with DIY movement) then the person does not deserve your audio interest

The typically-primitive audio people conduct random events and then talk about consequences

By comparison to the rest of society, I have observed that people who "do audio", are in general quite intelligent, articulate, and literate... Those who spend big money continually swapping components do what they do, knowing deep down that they are playing a game of chance, but they do have the cash and they do get some satisfaction (sometimes even sonically speaking) from this game. They frequently cannot defend their actions on logical grounds, but can easily afford to go on this way. Because they are otherwise intelligent, it is normal that they become emotional when asked to defend their illogic... Though it is kind of moronic, I find it human. They may even believe they have found absolute truth in audio... There are worse things to do with one's cash and time. I am however convinced that if given the chance to have their ears pointed in a more right direction, these people would take the event very seriously... It is a question of exposure. For now, they are trying to make sense of a lack of information. The sort of exposure that might help is not easily organized. I believe that in sound reproduction, any person can naturally recognize large-scale right from wrong, if presented with something that is more or less right...

My opinion is that there is simply a lack of "right" out there. This leaves those who "do audio" to extract "audio truth" from what is a pre-polluted base... Basically, subtly varying levels of what is in any case fundamentally wrong... Imagine the objective in Audio were to produce pure yellow (a primary color)... Its like we have been presented with a short cut to simulate pure yellow, which involves starting with brown and adding copious amounts of "negative violet" (violet being the compliment or opposite of yellow). And so rather than being subjected to varying levels of rightness, we get varying levels in the quality of the disguise which masks a nevertheless perverted origin.

Interestingly that at this point you might discover a completely new definition of the very common audio words: resolution, soundstage, imaging and the similar, however, then those words will have absolutely DIFFERENT meaning then for other people and you will push completely different buttons to get your new understanding of “resolution” or “imaging”.

You might discover a new ways to think and to talk about acoustic systems, or about audio generally

I have always been very uncomfortable using (or processing) "the accepted" audio vocabulary and perceptions... I think it has to do with a general dislike for code-heavy communication (all codes, including visual)... When forced to adopt too much code that is foreign to my own constitution my body starts leaking acid. This has been a source of unimaginable problems since birth! On the other hand, I admit that I can't resist employing these codes in a humorous context!

jd*

Romy quotes in blue (pulled from the "Adding one more channel to the Macondos" thread)

"1) Make sure that your cone is properly center in a gap. It is very important as misaligned cone will do compression at bottom end"

I feel confident that I am able to get the diaphragm centered... I don't fight it. It is also important to apply the same torque to all screws securing the diaphragm calmping plate. Those having experience with mechanical assembly will have developed a good feel for this sort of work.

"2) Make sure that the driver’s center are absolutely in the center of the horn and absolutely parallel to the horn’s axis. That is also very important with MF driver. If the driver does not sit in a perfect optical center of the horn then it will have very sever anomalies, particularly when the horn is towed in or out. With the spherical, low throat horns, as we have, it is very simple to misalign the center of the driver for a few fractions of mm"

To locate the S2s I use a plate made from 10mm thick aluminum, which is cut and trued on a lathe... the large central hole for the S2 is bored and threaded while still on the lathe. Six mounting holes are then drilled in the plate using a mill. This plate is then paired with a concentric spacer which allows establishing the axis of the horn as it is "turned". Once done, the S2 has no choice but to be centered.

Here are some images of the mounting plate and the process :


S2 with mounting plate (rear view)


S2 with mounting plate with spacer (front view)...
This spacer is of a thickness that corresponds to the
non-threaded tip of the nose of the S2.


Mounting plate with anchor (plates cost a fortune to
have machined, but the result is worth the cost)


Critical step part I : Verifying that the plate is centered
before locking it in place with hemp and plaster...
To do this the entire assembly is rotated on its axis while 
measuring and adjusting the clearance between the plate
and the stationary template (at right)


Critical step part II : Locking the plate
anchor in place with hemp and plaster


Plate and upper stabilizer amr (horn is done in this
image)


Done and waiting for the core to drop out

This horn required that I do a special little dance involving candles, insence, and a big rubber mallet before it would release the core... Next time I will film the ritual and post it on YouTube.

jd*

Ah, your horn this way does not have own axis and the axis of the back plate become actually the axis of the horn? This way you get rid the ugliest element of co-axising – the integration of the axis of horn and the back plate. Very-very cool indeed! I wish I was able to do it. My MF driver has two metal plates that have a few mm freedom between each other allowing them to be re-centered.

It looks like a very elegant solution of the centering problem but in practice it is not so elegant and more pain in ass. 

BTW, in your scenario the center pipe that is sitting in the throat looks like smaller then 1.5”. Does it mean that you will eventually open up the horn intake diameter with sand paper until the throat hit the S2’s output diameter?

Do not tell me that in order to do so you will be using the methods that Zeiss used in 30s when they polish their Leica!  Well, it will be one way to assure your new horns’ Wife Acceptance  :-)

jessie.dazzle wrote:

Very simple... The WAF has had enough of the horns... She's met a new guy and is throwing me and a few tons of plaster out of the house! Worst of all, she has custody of the cats! This will delay the project, as I have to find a new room that is large enough, then figure out how to move it all. This will not stop the project... Though I have not done much for the past month, I should be back to work soon. The exWAF and I are now "roommates" (!!!), and I have negotiated the continued use of the space to get the project (with the exception of the 45Hz horns) to a more or less finished state before moving it. I will post more soon (I'll see if I can get a shot of her throwing things... Clearly the new guy is not measuring up!... Meanwhile I'm doing my best to get him interested in horns...)

Was she just a women of was she a wife? If you get the new guy interested in horns then you can move in together and… throw her away and then just to “rent” women for a period.

To be a little more serious those “capital” projects do impact social live quite insistently. I sincerely hope that in your case the woman did not juts “had enough of the horns” but the true reasons were somewhere else…

The horns? I, perhaps as many other men, am fantasizing about the woman for whom a definition of happiness would be to have a honeymoon bed installed in a mouth of 18Hz horn. Unfortunately those lowest frequencies affect females in a way that it put them asleep (it is a biologically know phenomena)… so you might have vivid reproduction of cello but you will have vague female that goes along with that cello…

Anyhow, those properly done 50Hz horn projects are always a bitch and a person who do it always end up ether with divorce, or with death, or with hernia, or with bankruptcy. In many instances it is not as important how good the midbass horn was but rather the person ability to integrate the horn into the entire playback system AND into the entire persons’ life. In many instances it is way more “smarter” juts to pay off and to have somebody else to buld the damn 50Hz horns for you. As I understand it was what Ming Su did….

jessie.dazzle wrote:

I don’t have a pair of Melquaid DSETs. I drive the horns with a pair of Lamm ML2s, running full range. I use a second pair of M1.1s for lower bass. The ML2s are hard to fault. In fact at this point, I can only find positive things to say about them. When I finally identify a good reason (sonic) to do it, I will try building a pair of DSETs… If the 45 Hz horns don’t kill me first.

1)    If you are not in very large room and your bass section are not 90dB sensitive then take one of yours left ML2.0, bring it to right channel and drive with it the right’s channel bass system instead of M1.1. It will be mono and it will be ML2.0 driving bass and HF of your right channel. See if you like the result what ML2.0 does with bass. Be careful though. What I did this experiment it cost me $15.000 for another pair of ML2.0. If you do so then post what you discover.

2)    Driving your 4 horn from a single ML2.0 you might feel a need to slightly alter harmonic structure for one of the channels. You still might do it to a degree with a single ML2.0. The ML2.0 has 3 taps: 4 Ohm, 8Ohm and 16Ohm. You might run each channel from own tap. The more ML2.0 will be load then more harmonics and fewer transients you will have. Mitigating between the taps mapping to the channels it is possible slightly optimize the results with respect to the specific drivers.  Of course it would be more fun if ML2.0 expose outside 14-20 re-mapable sections instead of just 3 taps then you would have more leverage but it would be another story…

jessie.dazzle wrote:

Are you suggesting : 1) Running the upper bass horn from a second ML2 ? 2) Running the lower bass enclosures (sealed boxes) from a second ML2 ? 3) Running both the upper bass horn and lower bass enclosures (sealed boxes) from a second ML2 ?

jessie.dazzle wrote:

I don't expect there would be much benefit in running the lower bass enclosures (sealed boxes) from a second ML2s, but I could be wrong.

jessie.dazzle wrote:

I have not tried this... I had been meaning to make sure it would not some how result in damage before doing so (was planning to ask Lamm... Up to now I've been using the 16 Ohm taps).

jd wrote :
"...While I'm at it, here is another attached image showing the core..."

Well its been a long time since I've posted photos of the project... I'll be doing that now.

To start off, I noticed that the link to a previously available photo is no longer posted; this is normal, as I've since moved and no longer have the same ISP.

So, here is the missing image (and a couple more) loaded this time directly onto Romy's server... They are photos showing the core being removed from a 180 Hz horn.


Core dropping out


Core removal


Core ready for production of next horn

More photos coming.

jd*

Jessie, looks nice. I never did it myself and can not appreciate the labor went into it. Horn-wise everything looks well- thought out. I personally would probably go for a monopod frame above the midbass horn (mergeing it in middle) as I feel it make the architecture more elegant, more airy and visually less demanding.

One thing I would like to comment upon, knowing that you vent over the subject of women and playback. I certainly do not claim any expertise in this subject… but show me somebody who do?

Horn installations are ugly from female perspective. What however I discovered is that horns might be nicely camouflaged among plants and women generally love plants. I means the section of room with acoustic system might be presented as garden, with good taste it might look very natural and seems do not interfere with sonic objectives. For whatever reasons females’ psychology works in a way that when we try to humanize playback under the mask of family decor then females feel that we demonstrate care about THEM. So, with good gardening taste and smart lightening is it is possible to softening the “hobby”. Another “softening” might be the explanation that if you spend all your audio time and audio money for heroin then you would never leave rehabs or were dead from overdoes now

BTW, If you consider something like gardening then make sure that your Cats would tolerate in house plants. My Koshka hate anything alive in my home beside her. She hardly tolerates me……