soongsc said:
But this affects the music as a whole - not just the occasional note. EnABL *gains* depth - yet not noticeably so on-axis. I know the effects of global damping - the second coat of Microgloss did that for me, and the receded soundstage was accompanied by loss of high frequencies and detail. EnABL was an entirely different experience.
When I booted Windows - with the sound through my keyboard combo - to my surprise Eno's naff little boot-up tune came at me from behind the speaker. So it's not just in my more revealing system.
And it was entirely unexpected - so IMO unlikely to be psycho-acoustic.
FrankWW - makes sense, I must google "waveguide" and educate myself a bit here!
OK you COULD design and do a statistically valid randomised double-blind controlled trial. But a horrible amount of work with not much benefit to those who do it.
How about asking a loudspeaker company if they are interested. Outlay is low - just the time / effort. But surely their R&D guys are paid to do this sort of thing. Or is it all just market-economics?
I think putting an enabl pattern on a speaker panel, particularly the front panel, could make an audible difference but not for reasons discussed here. Lots, perhaps most, speaker enclosure panels radiate some sound from their surface. Enabl pattern may very well damp some of that sound.
Also:
Surface finishes do have a big effect on radiation characteristics. The German violin maker I referenced some pages back (and who is definitely a scientist) notes finishes used on violins have a great effect on their radiation characteristics.
Finishes can have have a damping effect of between about .75 and 3.00. Yes, some finishes can actually have an undamping effect of as much as 25%. Of course he is in the instrument making business and what he sees as desirable we might not, but I will take research where I can find it.
See "Acoustic Analysis of Violin Varnishes" in the Acoustics Research Section
http://www.schleske.de/index.php?la...eske.de/06geigenbauer/en_akustik3schall.shtml[/url]
Also:
Surface finishes do have a big effect on radiation characteristics. The German violin maker I referenced some pages back (and who is definitely a scientist) notes finishes used on violins have a great effect on their radiation characteristics.
Finishes can have have a damping effect of between about .75 and 3.00. Yes, some finishes can actually have an undamping effect of as much as 25%. Of course he is in the instrument making business and what he sees as desirable we might not, but I will take research where I can find it.
See "Acoustic Analysis of Violin Varnishes" in the Acoustics Research Section
http://www.schleske.de/index.php?la...eske.de/06geigenbauer/en_akustik3schall.shtml[/url]
Hey Alex and Terry
I am only 1 hr from Canberra and I am there almost every week (2 days) teaching digital workshops, it would be great to get together, or perhaps even in Goulburn where I live, I can provide facilities. Currently building a full OB based system with enabled drivers, plus all the rest of the system as well, including TT/tonearm/cart, Preamp, Powe ramps, Power supplies, Dac etc 15 lots of casework in total, it will be up and running in the next 2 months I hope. It would be good to share.
I also have some local audio guys who would like to listen, in fact they asked my just a couple of nights ago at a radio meeting if I could run some demos for them.
I must post some progress pics in the next couple of days.
I am only 1 hr from Canberra and I am there almost every week (2 days) teaching digital workshops, it would be great to get together, or perhaps even in Goulburn where I live, I can provide facilities. Currently building a full OB based system with enabled drivers, plus all the rest of the system as well, including TT/tonearm/cart, Preamp, Powe ramps, Power supplies, Dac etc 15 lots of casework in total, it will be up and running in the next 2 months I hope. It would be good to share.
I also have some local audio guys who would like to listen, in fact they asked my just a couple of nights ago at a radio meeting if I could run some demos for them.
I must post some progress pics in the next couple of days.
Alex from Oz said:
In my best 'Mr Burns' impersonation (twiddling my fingers)
"eexxxcelleeeent!'
Zero One said:
Good one Zero, the Goulburn/Canberra/Bathurst triad is pretty bloody good, no? I too can offer facilities and accomodation, but alas (apropos to this thread) no enable facilities just yet. Can provide some nice crankin tri amp goodness if desired, but that's for another thread.
soongsc said:
It does Soongsc, good onya for being 'world aware' if that is a valid description. It is an amazing building.
I will never forget that trip which was the hardest rain I've ever experienced in my life. That picture was teken a few hours before we experienced the rain heading towards Melbourne (I think). We were in the middle of nowhere, the rain was falling so hard it sounded like hail falling on the car, we could see about 3 meters in front of the car.terry j said:
soongsc said:
Ahh, your own personal photo eh? I hope you enjoyed your trip here, and if you ever do it again please let us Aussies know and I'm pretty sure we can offer you accommodation etc, might be of some small use to you.
Funny re the rain, most of Australia has been in drought for nearly a decade, now in some places it's starting to break. In Mackay (is it?, don't really recall) we have heavy flooding...something like 600 mm in six hours. Boy, that's hard to imagine. Real tropics type stuff.
typical Australia, drought, then bushfires, then flood.
then the cycle starts again.
t-head said:
It's an open forum, or so I thought. If you want a private discussion, email is the way to go.
Dave
Alex from Oz said:
There will not be any measurable changes. I've spent enough time over years of measuring and testing for diffraction specifically to know that it will make no difference whatsoever.
Dave
BudP said:
Bud, again, please open even a basic text book. As an acoustic wave propagates through air it imparts a pressure and velocity variation to the air (air molicules if you like). The energy flux is just
E = Pu
where P is the pressure and u is the velocity of the air molecules in the direction of the wave propagation.
We typically write
P = Po + dp
where Po is the undisturbed pressure and dp is the pressure perturbation caused by the acoustic wave and the energy flux is written as
E = Po u + dp u
For a wave in free space, dp and u are related by the characteristic impedance of air,
dp = Z u
so
E = Po u + Z u^2
For a periodic wave the average energy flux over a period is then given as
Eave= Z (u^2)ave
where (u^2)ave is the mean-squared particle velocity. The Po terms drops out over a period because the average velocity is zero (but not so for u^2). So when you are talking about energy flow, or energy flux, you are most definately talking about the fluid motion.
When we consider energy transfer from material to material (cone to air) we are again considering the velocity of the air in contact with the moving surface and the surface pressure variations this generates. This energy transfer takes place at the interface, not off the interface or somewhere above or below the interface.
FrankWW said:
Excuse me for replying to a post not directed to me (that upsets some folks), but I agree with pretty much everything you've said. This is the approach that I had hoped some might take, logical reasoning. The enabl pattern is unique and adds mass in distributed fashion with some localized stiffening and possibly damping. The relative levels of each is unknown and will change with every diaphragm. The mechanism has all the empirical evidence of distributed mass altering resonances due to the mass and is borne out by literally every measurement posted. The physics support that fully. Other mechanisms have no support in the physics presented, neither by proponents (none to date) nor by skeptics.
The point about stiffening is, I think, the key to the tweak I add to the surround, the one manufacturers started using decades ago. It seems to be primarily a stiffening at the surround roll/flat area section. This causes the flexing to occur higher up into the roll rather than down low near the bottom of the roll section. Some newer drivers have more expensive surrounds such as most of those by Scan-Speak and the Vifa PL series that have a gradual curve on the cone side rather than being a pure half-roll surround. This looks to be designed for the same purpose.
The one problem is that as can easily be seen in the tests I posted and as you point out, adding mass may indeed worsen a driver. Until it is measured, there is no way to know precisely what changes were introduced.
Dave
There was a reasonably smart guy once who came up with a theory. F=m x a. And so it was, and that was the way the world worked. You could prove it with MEASUREMENTS. Except then along came improved technology and some other smart folks who found out, to a certain amount of derision, that this little handy equation wasn't the whole story. Yet now we accept those theories as facts of life. What next?
I'm not at all surprised there might not be an easy explanation, using current theory, for what EnABL does (IF it does). Maybe there's a simple explanation or maybe we need to question our underlying assumptions and rules. But if you're stuck in your textbooks and your theoretical comfort zone, or refuse to accept there might be a change, you won't be the one to find the answer.
I hear two primary voices on this thread; those who accept that there is or might be an effect and seek explanations, and those who seek to discredit the others. Challenges to the first group are crucial. It's just too bad that it's being done with such personal attacks here. I don't consider those who resort to personal attacks as scientist. It suggests an insecurity in your ideas.
Carl
I'm not at all surprised there might not be an easy explanation, using current theory, for what EnABL does (IF it does). Maybe there's a simple explanation or maybe we need to question our underlying assumptions and rules. But if you're stuck in your textbooks and your theoretical comfort zone, or refuse to accept there might be a change, you won't be the one to find the answer.
I hear two primary voices on this thread; those who accept that there is or might be an effect and seek explanations, and those who seek to discredit the others. Challenges to the first group are crucial. It's just too bad that it's being done with such personal attacks here. I don't consider those who resort to personal attacks as scientist. It suggests an insecurity in your ideas.
Carl
Thanks John.
I am willing to set aside the Boundary Layer question. This was given to me by Ned Nestorovic, one summer afternoon. At the time he was doing graduate level studies, in boundary layer research at Stanford. He was pretty emphatic that what I had just shown he and his father, a fully EnABL'd pair of Mark 5 speakers, exhibited drivers that were utilizing a boundary layer to effect the pretty obvious, audible changes.
He offered to "do the math" if I could provide the tests. Mile' immediately said no. That EnABL was going to provoke the most astonishing sort of warfare imaginable and he did not want Ned in the middle of it, as his reputation would be permanently damaged.
Up to that point I had no theory that might predict what to do to further use the patterns. It was at that point that I first treated a baffle and shortly thereafter, in a visit to my home town the band shell. That these treatments worked exactly as well as treating a speaker just reinforced my acceptance of a boundary layer as the operating mode.
Let me offer a compromise here. It is fairly obvious by now, that if we can fit EnABL into accepted theories, you will be delighted to move the investigation further. Is this a correct assumption?
If so, I will set aside Ned's very seductive model. In exchange I want you and dlr to listen carefully to my descriptions of observed phenomena. Then we must look for what might be the mechanism, in a cooperative fashion.
The EnABL patterns are like some kind of audio Swiss Army knife. They solve some very real problems. More of them than we have discussed to date.
Just like anything that solves many problems, it is unlikely to be the best tool for any particular one. However it does give an avenue into solutions for all of them. I do not expect the EnABL patterns to be anything more than a road map for what can be done, but it will have to be accepted for what it does.
Since all of the initial descriptions are going to be observed, anecdotal reports, you are going to have to take them at face value and Dave is going to have cease denying an observed phenomena as a reality, because it does not fall within his current level of experience. Each of them must be questioned carefully and closely so that we can be certain that all of us have the same definitions for the words we use. Then we can actually look into the events.
EnABL does not fall within anyones current level of experience, until you have actually experienced it. I don't care how hard this may be to accept. What is likely even worse is that there are some aspects of observable phenomena, that EnABL brings about, that are really mystifying. That appear to require a reciprocity with the environment that is not comprehensible in a rational fashion, based upon any physical model I have found. Yet, they, like all of the already argued over phenomena, are observable.
It is entirely possible that EnABL is altering the structure of the emitted sound waves in such a fashion that they are just more easily interpreted by our correlator. And that this is done without actually doing anything different than the classical model of a direct radiator as a bending wave device, with pistonic characteristics over a small portion of it's operating range. That is fine. But, it is still a startlingly effective avenue, into solutions for current problems with audio transducers and their support structures that it is quite novel and far reaching.
Can we all agree to this organizational model?
Bud.
I am willing to set aside the Boundary Layer question. This was given to me by Ned Nestorovic, one summer afternoon. At the time he was doing graduate level studies, in boundary layer research at Stanford. He was pretty emphatic that what I had just shown he and his father, a fully EnABL'd pair of Mark 5 speakers, exhibited drivers that were utilizing a boundary layer to effect the pretty obvious, audible changes.
He offered to "do the math" if I could provide the tests. Mile' immediately said no. That EnABL was going to provoke the most astonishing sort of warfare imaginable and he did not want Ned in the middle of it, as his reputation would be permanently damaged.
Up to that point I had no theory that might predict what to do to further use the patterns. It was at that point that I first treated a baffle and shortly thereafter, in a visit to my home town the band shell. That these treatments worked exactly as well as treating a speaker just reinforced my acceptance of a boundary layer as the operating mode.
Let me offer a compromise here. It is fairly obvious by now, that if we can fit EnABL into accepted theories, you will be delighted to move the investigation further. Is this a correct assumption?
If so, I will set aside Ned's very seductive model. In exchange I want you and dlr to listen carefully to my descriptions of observed phenomena. Then we must look for what might be the mechanism, in a cooperative fashion.
The EnABL patterns are like some kind of audio Swiss Army knife. They solve some very real problems. More of them than we have discussed to date.
Just like anything that solves many problems, it is unlikely to be the best tool for any particular one. However it does give an avenue into solutions for all of them. I do not expect the EnABL patterns to be anything more than a road map for what can be done, but it will have to be accepted for what it does.
Since all of the initial descriptions are going to be observed, anecdotal reports, you are going to have to take them at face value and Dave is going to have cease denying an observed phenomena as a reality, because it does not fall within his current level of experience. Each of them must be questioned carefully and closely so that we can be certain that all of us have the same definitions for the words we use. Then we can actually look into the events.
EnABL does not fall within anyones current level of experience, until you have actually experienced it. I don't care how hard this may be to accept. What is likely even worse is that there are some aspects of observable phenomena, that EnABL brings about, that are really mystifying. That appear to require a reciprocity with the environment that is not comprehensible in a rational fashion, based upon any physical model I have found. Yet, they, like all of the already argued over phenomena, are observable.
It is entirely possible that EnABL is altering the structure of the emitted sound waves in such a fashion that they are just more easily interpreted by our correlator. And that this is done without actually doing anything different than the classical model of a direct radiator as a bending wave device, with pistonic characteristics over a small portion of it's operating range. That is fine. But, it is still a startlingly effective avenue, into solutions for current problems with audio transducers and their support structures that it is quite novel and far reaching.
Can we all agree to this organizational model?
Bud.
Dave, it depends on what you're looking for, I think. It may well be, for instance, that front mounting plate is itself radiating sound. (It wouldn't be a first.)
Alex has a pretty sophisticated damper - double sided tape with gold foil on top, and arrayed in a pattern could well damp sound radiated by that plate. How you might measure that could be a tricky thing.
It certainly is nice to see positive experience posted here. For those that are skeptical, I would recommend just listening first. If the results are what you think you enjoy, then try it. The reason behind listening first is to make sure that we can understand what the optinion of others truly mean compared with our listening experience.
I've been visiting a CD store quite often, and the pair or Raurk (did I get that right?) speakers they have there just makes most CDs sound real nice. I doubt it will measure well in technical terms, but certainly fits it's purpose quite well and enjoyable to listen to even if the fidelity is not perfect.
I've been visiting a CD store quite often, and the pair or Raurk (did I get that right?) speakers they have there just makes most CDs sound real nice. I doubt it will measure well in technical terms, but certainly fits it's purpose quite well and enjoyable to listen to even if the fidelity is not perfect.
dlr said:
dlr,
OK, lets set aside the 'measurement' issue for now.
The primary issue is whether there is an audible difference when EnABL is applied.
You still have not answered my first question: 'Have you listened to an EnABL'd driver?'
You lack of response leaves me to assume that you have not.
I proposed a straightforward and fully reversable method for applying EnABL specifically to your system that completely eliminates the involvement of added mass to the driver.
This could easily be done in around 1 hour.
Then I asked: 'Are you prepared to try this?'.
You haven't clearly answered this question.
It is obvious from your webpage that you spent considerable time and energy applying 'dots' to your cones and measuring outcomes.
So let me again ask directly:
Are you are prepared to apply EnABL as I have described and simply listen for any audible changes?
Alex from Oz said:
Hi,
You have confidence that painting the pattern on the plastic ring that surrounds the driver will make a difference?
THAT would really be something.
Oh, but gold foil will shift the BL to the right and lower FR bypass syntax...in a measurable way of course!
🙄
🙄
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