Romy the Cat wrote:

I can’t see the pictures. What I was thinking to connect the ribbon’s array in series and drive them with one custom better Bad’s transformer. Or perhaps if it were I would say .3R ribbons then 5-6 drivers would make a couple Ohms and this impedance would be possible to drive by a dedicated HF channel with a special OPT, eliminating that, perhaps compromised, China-made transformer in the each tweeter… What do you think?  It might be an interesting project….

Gentlemen,

I suppose it is time to defend my sterling reputation here. The EnABL process does in deed work across the full frequency band. Works on all driver types and permits the very qualities that Romy seems to appreciate in the treated Linneum tweeters.

The process controls the boundary layer, absolutely. Since the boundary layer of any emitter completely describes what can and cannot be emitted into the adjacent air, or water, to control it's spurious ringing, without deconstructing the coherent transient information in both micro and macro signals, is rather important. Since the boundary layer is amenable to lateral control mechanisms, being a carrier of lateral compression waves as they express into the adjacent medium over a period of time, a low mass diffraction grating at both ends of the membrane will perform a multitude of important functions.
The simulation of an infinite length between terminus edges. In this the energy density in the boundary layer, through the flat wave diffraction grating, is far greater than on either side of the grating. This forces energy that has passed through and is now at the edge of the membrane to exit the edge. This remaining energy will exit in phase and time coherence, with the energy already expanding into the adjacent air. Theoretically there are tiny diffraction artifacts from the grating blocks, back into the boundary layer, but they are extremely small in amplitude and have no chance to form a standing wave.
The elimination of null emitter bands within the boundary layer allows phase and time coherent emission into the surrounding air as the wave front crosses the emitter surface.
The amount of mass required to effect this control in a 6.5" mid/woofer is equivalent to writing your name, in script on an 8.5" X 11" piece of paper with a ball point ink pen. This relationship holds true regardless of the size of the emitter being processed. So, this is not a bulk mass damping system. It is instead a mass damping, of sorts, of the boundary layer, in the lateral plane only. Since the boundary layer is a very low mass high energy area, a small amount of mass, relative to the total emitter diaphragm mass, is all that is required for complete control of reflected energy that would otherwise form standing waves.

What has always fascinated me about this process is that it works on woofers, well below their natural piston point, so it even controls the emitted energy with wave lengths far greater than the dimensions between rows of the applied pattern.

What it removes is exactly what Romy is complaining of, the uncorrelatable sound that is left over as transient ringing, from the passage of a wave across an emitter surface. It also brings some other benefits but this is the most important one and a full range system controlled in this fashion does not emit ANY spurious information. Nor does it exhibit ANY colorations from the drivers. Nor does it have any "location" perceivable in a stereo spread. And last but not least, there are no limits to the resolution available.

I am aware that this sounds fishy, many others have made the same claims and then failed to perform. I welcome any audiophile, who cares to journey to the west coast, to come by and listen to a full range system treated in this fashion.

You can even poke and prod around, looking for the hidden alternate reality generators.

This is real and it does work.

cv wrote:

Ok, I managed to get my measurement setup running. Behringer ECM8000/PC soundcard kind of thing. I measured the following tweeters: Focal TLR TAD PT-R9 Aurum Cantus G1 Fane 5022 I don't have an absolute level calibrator and I need to take time to try and make the measurements accurately, ensuring the distances are correct in each case. But having said that, if we assume each of these drivers is an 8 ohm load (I left the signal level and gains untouched), then I measured, in relative terms, sensitivities commensurate with the makers figures. In other words, the TLRs (rated at about 95db/W and coming with individual calibrated response plots) were a db or two less sensitive than the PTR9s, which in turn were a bit less sensitive than the G1s. Early indications are that the 102db/W is off for the G1. They don't sound like 102db either. But I think the PTR9 spec would seem to be honest, at least with my units. The Fane has such a crappy humped response it's impossible to draw any conclusions there! Anyway,  this is very rough - will try and find time to take some more careful measurements later in the week, hopefully tomorrow.

Well, Chris, I need to check out my other PT-R9 driver. Perhaps the one that I tried was discharged … I do not think so but I will do it within a day or so.

BTW, currently my completion for more interesting high sensitively ribbon tweeter looks like coming to the end and it is possibly that you will be the winner. I spoke today for a quite long time with the proposed by you RAAL’s Alex and I like the guy quite a lot. He has very valuable from my point of view combination of knowledge and desire to use his expertise in applied manner to benefit the objectives of my project. I have very-very pleasant feeling about him and I very much like how he thinks. We did not decided yet but perhaps we can cook a custom 107dB ribbon driver. If we move forward then you will be declared a winner and that BMW Z4 Roadster will be shipped to you.

Thanks,
Romy the Cat

PS added in a few hours: Chriss, I juts got another PT-R9 from the box. I did not measure it but just A/B the subjective output of the both tweeters and I confirmed that they are identical. I was pretty convinced that it would be the case. The only explanation that I might see is in the efficiency of my room at HF. I have, as you remember, quite a lot of going on in my room that reduces the room response at HF (all that hanging thing, the book and record shelves, the cats t-shorts and so on…) Perhaps it is that eats the affectivity HF in my room. 9dB, Hm, quite a lot! I never consider my room over-dumped but it defiantly never was “live”. I really am not wiling to change anything with the sound of my room. Probably it is better to continue beaching about the tweeters manufactures….

Paul S wrote:

I can report that the G2Si loses the "glycerin" at 10k with the ML2s….

I concur with this finding. Any ribbon tweeter that I heard has "glycerin" tone but it is because the ribbon mostly crossed too low. I would say that I still head some trace of the "glycerin" at 10K with second order but I have no trace of it at 13K. It would certainly wary from driver to driver but definitely a ribbon sharply closed at 10K sound nothing like a ribbon crossed at 6K. I still do not know what I will end up but I at this point do not worry about the ribbon's alien glycerin tone. Cross ribbon higher and use HF capable MF drivers -  it would be the best solution do not poison system’s sound with the “ribbonninnessththzzz”….

Paul

The entire pattern shrinks and grows geometrically, based upon the physical length of the edge of diaphragm involved. Please understand, this is not just a theoretical idea, I do and have done this process on many different types and sizes of drivers. I even have a basic amount of pattern application that is quite generic and has worked with equal success in all cases.

Please look above, for either the PDF or the link to a published copy and read the white paper for the EnABL process. It discuses the various types of causes for driver induced transient standing waves. There are some standing waves that cannot be treated with this process, but, since the driver engineering revolution two decades ago, there are very few drivers left with this sort of endemic limitation.

So, the pattern is applied with a technical pen, using a scaled pattern based upon the physical sizes involved, for the normally tiny drivers used in high frequency applications.
When the driver sizes scale beyond these pens I use calligraphy pens for their uniform flow rate and variety of sizes. With these simple tools I can treat anything from .5" in diameter dome to an 18" in diameter woofer with the same materials, though the material when used in the technical pens is thinned by a specific amount.
I am only interested in the few thousandths of an inch on any driver surface that comprises the boundary layer. And that few thousandths of an inch does control the rest of the drivers standing wave characteristics. This is really just a matter of having found the proper fulcrum.

I am located in the Seattle area, so we are quite far apart by horseback. UPS and FED EX do a pretty good job of carrying boxes full of speakers back and forth though......

Paul S wrote:

Piezos, anyone?Paul S

I have a local friend of mine lent me PHY TW37 tweeter. It is French-made piezo driver:

http://www.phy-hp.com/English/Products/TW37_E.html

I was running it last night and it was not as horrendous as I was expected. In fact it was almost nice. I do feel some “heaviness” in the sound of this driver, perhaps because it has fixed 12db/octave filter at 10kHz (too low for me) of because it users a relatively heavy paper cone. Also, the topmost region is kind of “dullish” to be a tweeter. I would feel more comfortable to use this driver as a “lower HF tweeter” then the “all-around tweeter”. I think that the “heaviness” in this tweet might be also because it futures a cone that sits in the moth of a little horn-like… horn and effectively acts as a reentry horn. The “horn-like horn” is filled with cotton that does absorb the highest frequency but should be less absorbent for lower knee of the HF.

Anyhow, dispute of everything, form this French-made piezo driver sounded more balanced then I expected. The biggest problem, in my case, was that this tweeter does have a deferent sound with my Vitavox S2 driver. If with Linaeum/TAD PT-R9 ribbons I might set them in a way that a deference between S2 and Linaeum/TAD PT-R9 would not be acknowledgeable then with PHY TW37 I was not able to do so It is not only about the fixed crossover point of the TW37 but rather different ability to be accelerated with dynamic and frequency range between this tweeter and my MF driver. All of this creates a different “feeling” of Sound…

Stull, the ribbons so far are leading the race…

Vitavox S2 does OK up to 12.5K ("strong, clean and in character") on it’s center but I never use this driver pointed directly to me but rather at good 20 degree off. (I hardly can tolerate any compression driver point directly to me). At my angle the S2 in my 400Hz horn is well attenuated, more civilized and behaves more or less appropriately. In my listening position S2 does approximately 10K but the numbers are kind of meaningless in there as the HF “transient feel” is still there. In fact juts with S2 and no tweeter is it VERY much listenable, I do not know how to explain it though. Any tweeter, of any topology that I’ve used, if I set it to 10-11K made everything too bright. Or better I would not say “too bright” but rather “too unnecessary” as it screw with the “S2’s transient phantom presents”. I feel that in the world of HF it is not exactly about measurements (at least to me) but rather to dial-in the exact necessary amount of HF’s touch – juts a very-very slight inflection atop and it is it. The S2 is not Altec and not JBL and it does not need “help with HF” but rather “a complement of HF”. I do not know now other people but when I try to add HF to S2 driver I always have problems with the fact that I drive a tweeter at so low level that it is become not effective at all. In any case, it is relay hard to describe it as it need to be heard to understand how it works. When I turn volume control on my dedicated separate Milq that drives now tweeters and when I set this volume at the level when I feel it is “enough” then my RTA shows many-many db down at 12K (and my instrumental microphone is well calibrated). I never had a tweeter that I would be able to listen at -3dB at 12K. Anyhow, I hope ribbons would help me to fix this tendency…. if it need to be fixed…

Paul S wrote:

I am glad to hear that I am not the only one who is overwhelmed by compression drivers.  I tried the A7s way back when they were current and everyone's favorite, and I tried various modifications with like-minded friends; but I came to the conclusion that the only way to do the horn thing would be with theater-type "dedicated" amps driving narrow band horns that did not really load down into their horns.  It was just too much for me at the time, and I lost interest in the horns.  And now you say that you still have to listen well off axis...

In fact Altec drivers are too soft anyhow. The real secret in this (people juts do not get it) is to make the properly operating horn line-array, properly ingrate them and balance the entire sound, allowing the off axis equalization (particularly with phase plug drivers)…  But it would be a subject for other thread...

Paul S wrote:

I know one can't be certain in advance, but the way you describe your high frequency wants, it sounds like a perfect fit for either a small ribbon or a small 'stat, or an array of either. A lone ribbon may actually have some horizontal dispersion, but the electrostatic panel really benefits from the array, which eliminates that beam-y quality and that stupid in-and-out thing when you move you head at all.  I hate that!

I was thinking about the electrostats for years. I hate how they sound and I think that heard a lot of them. The problem is that to do the electrostats properly - direct couple them to 3kV plate - it juts too much work to do for a driver the will be covering 1/3 octaves…

Paul S wrote:

And I will say again that I'm not in this for DIY; I really would just buy everything if I thought I could wind up with what I wanted that way!

It is EXECLY how I feel. If I have somebody to whom I would pay to renders my requirements then I would never bother to educate myself on the subject HOW it might be done. Somebody who “can” is loosing a lot of money not to having my phone number in his phonebook.