BudP said:
Hi,
I have no doubt EnABL does something on cones which varies with
the actual driver and that that change is testable and subjectively
apparent.
I do have doubts about EnABL on solid edges. I suggest that it
will not be possible to objectively show reduction / elimination
of diffraction effects, end of story. It may have some minor
effect which may be subjectively apparent but technically
speaking it does not do what is claimed.
I have no issues with the EnABL process- its a described process.
I do have issues with the claimed "technical" details. Its mumbo-
jumbo and not much to do with real world physics and acoustics.
Ignoring the subjective claims for the effects of EnABL, the objective
descriptions of the how EnABLing works are pure fantasy. I can only
assume you wrote the patent with your tongue firmly stuck in cheek,
and its the proponents of this "theory" I have a problem with.
It is futile to try and analyse something whilst at the same time
making up theories for phenomena that are not known to exist
and reinventing the laws of physics as you go along to suit.
EnABLing technically does not do any of the things described in
the patent so said technical details cannot be demonstrable.
Consequently as a process it is nowhere near as radical as a process
that would achieve some or any of the claimed technical details,
of the ones that do make some sense as opposed to the ones
that are innaccurate, irrelevant or nonsense (as in no sense).
People try EnABLing and they say it gives worthwhile improvements.
Fine.
How it does this is and quantifying what it actually does is going
to turn out to be far more mundane that the rather spectacular
gobbledygook in the patent.
/sreten.
Sadly we see few people using this technology to improve sound. It is not easy to obtain the best possible results for each driver.
There have been some experiments that I made that seemed to improve sound under certain circumstances, but then when I get to certain music, the defficiencies appear. Not knowing what sources others use, I normally try to identify certain specific tracks that seem to reveal difficiencies more easily. In each of these sources, I like to take much time to appreciate the music, the techniques of the performer, and the specific qualities of the instruments being used. If instruments are the point of focus, I like to choose the kinds I can easily/ or have already experienced live and unaplified performance.
In some of the graphs I have posted, there is cone breakup 18KHz~22KHz which extends beyond 0.38ms. This becomes tolerable when the level is about 15db below the main signal level, but still audible. In this particular case, the cap is the main source of the problem, and I suspect it would also be for other designs with VC caps as well for very good reasons if one understands how energy is dissipated.
For drivers that do not show very concentrated cone breakup modes, these are probably the drivers that will benefit most from the EnABL process.
There have been some experiments that I made that seemed to improve sound under certain circumstances, but then when I get to certain music, the defficiencies appear. Not knowing what sources others use, I normally try to identify certain specific tracks that seem to reveal difficiencies more easily. In each of these sources, I like to take much time to appreciate the music, the techniques of the performer, and the specific qualities of the instruments being used. If instruments are the point of focus, I like to choose the kinds I can easily/ or have already experienced live and unaplified performance.
In some of the graphs I have posted, there is cone breakup 18KHz~22KHz which extends beyond 0.38ms. This becomes tolerable when the level is about 15db below the main signal level, but still audible. In this particular case, the cap is the main source of the problem, and I suspect it would also be for other designs with VC caps as well for very good reasons if one understands how energy is dissipated.
For drivers that do not show very concentrated cone breakup modes, these are probably the drivers that will benefit most from the EnABL process.
soongsc said:
Why? Isn't the reduction or elimination of resonances the sole purpose of EnABL? Re-reading the patent would indicate that drivers with significant breakup modes would be more appropriate for treatment, not less. I'm puzzled by how often changes are made iin various areas in this thread related to what should or should not be done.
The patent also states
This due to standing wave reduction (all of the above measurable, of course).
Hmmm, I recall having responded to a question very early on that a full set of standard on- and off-axis frequency response measurements along with a full set of standard, well-known and used distortion tests, both linear and non-linear, be made and/or provided. Somehow, back when I suggested this, I was taken to task, pretty severely I would add, for having asked for the same tests that I now see are specifically designed to provide evidence for what is outlined in the patent.
Kind of makes me wonder why there was so much resistance to the suggestion that there exists today a method to prove/disprove the effects regardless of the mechanism and even more curious now that I see that it was laid out in the patent by implication in the "Summary of Invention".
Dave
dlr,
The only part of the discussion you leave out is the portion where I and also those who have also run tests, said we could not find a result that even remotely correlated with the audible effects. Since that time you have pointed to two isolated changes in a FR/CSD plot that you otherwise strongly challenge, as indicative of a significant change brought about by an EnABL pattern. I am certain you meant what you said.
Jon Ver Halen provided test data that showed no change or in some instances an actual deterioration of response, when EnABL was applied. In a later subjective test, numerous people were exposed to an A/B test of the drivers used in the quantitative tests Jon ran. The A/B comparison was just that, no scientific rigor was intended. The results have been reported on the thread and they have caused a few able folks to decide to test for themselves, both qualitatively and quantitatively.
The patent and the white paper both refer to transient standing waves, not systemic standing waves. A systemic standing wave is what is typically known as "breakup mode" We saw four of these modes in John K's CSD of an untreated aluminum driver and EnABL dispersed one completely and in general smoothed and removed other erratically arising energy, throughout the frequency range. I still applaud his work. This is the first CSD, other than the one performed for the white paper, done with a program that used a chirp rather than a known noise field for stimulation, that seems to display what EnABL has always been aimed at doing.
I am now reasonably sure we can at least find evidence of what the patterns are doing. I am not yet convinced we can find out the actual mechanism or how related to subjective response these tests are. John K has already stated that he does not think that the typical battery of tests is going to show us much more than it already has and he is moving on to FEA, just as Dan Wiggins has already done.
Sreten,
Were you involved in this thread when John K posted his mass loaded cone CSD plots?
John K,
Would you object to someone else mounting the plots of the EnABL and plain cone CSD again? I would strongly prefer that all of the results be put up, just to present a fair comparison, but this is your data and I do not want to assume ownership of it unless you are willing.
Bud
The only part of the discussion you leave out is the portion where I and also those who have also run tests, said we could not find a result that even remotely correlated with the audible effects. Since that time you have pointed to two isolated changes in a FR/CSD plot that you otherwise strongly challenge, as indicative of a significant change brought about by an EnABL pattern. I am certain you meant what you said.
Jon Ver Halen provided test data that showed no change or in some instances an actual deterioration of response, when EnABL was applied. In a later subjective test, numerous people were exposed to an A/B test of the drivers used in the quantitative tests Jon ran. The A/B comparison was just that, no scientific rigor was intended. The results have been reported on the thread and they have caused a few able folks to decide to test for themselves, both qualitatively and quantitatively.
The patent and the white paper both refer to transient standing waves, not systemic standing waves. A systemic standing wave is what is typically known as "breakup mode" We saw four of these modes in John K's CSD of an untreated aluminum driver and EnABL dispersed one completely and in general smoothed and removed other erratically arising energy, throughout the frequency range. I still applaud his work. This is the first CSD, other than the one performed for the white paper, done with a program that used a chirp rather than a known noise field for stimulation, that seems to display what EnABL has always been aimed at doing.
I am now reasonably sure we can at least find evidence of what the patterns are doing. I am not yet convinced we can find out the actual mechanism or how related to subjective response these tests are. John K has already stated that he does not think that the typical battery of tests is going to show us much more than it already has and he is moving on to FEA, just as Dan Wiggins has already done.
Sreten,
Were you involved in this thread when John K posted his mass loaded cone CSD plots?
John K,
Would you object to someone else mounting the plots of the EnABL and plain cone CSD again? I would strongly prefer that all of the results be put up, just to present a fair comparison, but this is your data and I do not want to assume ownership of it unless you are willing.
Bud
BudP said:
This is subjective interpretation that is not related to the objective reality. As John has said more than once (attempting to paraphrase here) the problem is that the subjects basing changes on perception were unable to make a correlation. That has nothing to do with what observable changes occurred, regardless of where or how. Denying the objective changes or being unable to make a correlation to known changes does not alter the facts.
I meant what I said, but that is not what I said. I did not provide a detailed analysis at all, I pointed out what should have been obvious, that being the gross changes, not all good, either, as you have been leaving out. There was an introduction of a significant resonance as well as other changes higher in frequency. The rest was left without comment as the point was made, that being to show the glaringly obvious changes that every proponent missed entirely or preferred to let pass without comment. That post simply highlighted the fact that there are objectively measurable changes that up to that point were being denied.
That is all good. If anyone cares to modify their drivers, it's their choice. I have never said that they should not. I have said that they should be aware that it could be detrimental, the latter usually remains unsaid.
A standing wave (resonance) is a standing wave. It takes time to establish since it is due to a reflection. There are various modes in a driver (radial and concentric) with multiple orders, but they are all simply standing waves and should be controlled if EnABL controls standing waves as claimed. It does not, it alters them, as John has pointed out. If they were eliminated, you would see a driver's response change as he described in his much earlier post demonstrating what a driver's response would look like if standing waves actually were controlled.
We do know, they alter the resonances, but do not eliminate them all and they can introduce new ones. This has been supported in all data presented to date.
I believe as John, unless there is some proof presented that the mechanism is anything other classical mechanics, I certainly am not going to believe it to be anything but that. Others may believe what they want to believe. So far, there's not a single bit of evidence that it is other than classical mechanics. All data to date support classical mechanics to be the cause.
Dave
BudP said:
I have no objection to someone else posting them. But since many of them are not enable patterns, I don't know that they are particularly relevant.
With regard to standing waves, I would differ in any qualification of whether they are transient or steady state. Standing waves only occur at resonant modes. The resonant modes are just a consequence of the structure of the vibrating system. The modes don't change under transient or steady conditions. What we really have here, and what breakup is, is a limit cycle. If energy is feed to a system at the frequency of a resonant mode the amplitude of vibration at that frequency will build over time (transient) until the dissipation of energy per unit time is equally to the influx of energy per unit time at which point the resonance reaches a steady state amplitude (limit). The characteristic of the resonance, for example Fs and Q, indicate both the transient and steady state behavior. The decay of the vibration after the energy input is cut off is also dictated by the Q of the vibration. When the behavior of a standing wave is analyzed in the time domain there is always a transient rise to the steady state value followed by a decay when the input is removed. If the input is removed before the steady state amplitude is reached the decay just starts when the input stops. The figure below shows an example of these two cases. At the left the input is curtailed after 5 cycles of a sine wave. At the right the input signal is constant. Note that the rise in the signal after 5 cycles is the same for both cases. The rise in the output is greater than the input because energy is building up in the system since initially it is dissapated at a rate below that for which it is input. Since the dissapation is proportional to the amplitude of the system output, the steady state amplitude represents the amplitude at which enery input per cycle = energy dissapated per cycle.
An externally hosted image should be here but it was not working when we last tested it.
Please realize that the phase in the right figure is inverted compared to the left and the input starts 1/2 cycle later. Neither alters the result.
I'm sorry Bud, but your attempt to distinguish between symmetric (steady) and transient standing wave behavior once again obfuscates reality. It's just more technobabble.
john k,
The abrupt nature of your response is perplexing.
I simply asked for clarification on whether you applied EnABL inside the ports.
At this stage there is no ideal or correct method for doing this.
If you did put EnABL inside the ports and there was no audible difference, that's fine.
But, why are you refusing to answer any of my questions?
Good graphing John.I am still unbiased.
I had a tech run the drivers thru several different frequencies at 100 Hz increments from 500 Hz to 1 Khz.
Now heres the tickle. The noise changes in two(2) different axis in relation to the position across the cone(previous test). The noise also changes in position across the cone surface according to the frequency input. I do not believe this is a break up position as the same result would occur at a 90 degree measurement.
Now i have no idea what the additional coating effect can be(mass loading?), and without having a treated/untreated cone all i am doing is establishing a data base.
ron
( I may be slow, but i am steady and usually pound away at a question until i have a workable answer)
I had a tech run the drivers thru several different frequencies at 100 Hz increments from 500 Hz to 1 Khz.
Now heres the tickle. The noise changes in two(2) different axis in relation to the position across the cone(previous test). The noise also changes in position across the cone surface according to the frequency input. I do not believe this is a break up position as the same result would occur at a 90 degree measurement.
Now i have no idea what the additional coating effect can be(mass loading?), and without having a treated/untreated cone all i am doing is establishing a data base.
ron
( I may be slow, but i am steady and usually pound away at a question until i have a workable answer)
From John K:
From Sreten:
And from dlr:
OK, I get it. Nearly 3,000 posts later, there is fairly broad agreement that there IS a change that is audible, and Bud's "mental model" of the forces at work isn't correct. Great! Now can we move on to trying to figure out just what IS going on, and drop all the hoo-hah over Bud's theories? That might actually advance this thread.
Until that happens, I'm outta here.
Carl
PS - John K, I agree, Bud's model certainly doesn't suggest any greater significance and is probably not any more accurate. I just asked out of curiosity, since the implication I thought I heard in your post of the model was that it could be a definitive tool for evaluating EnABL. I get tired of scientists misusing and misunderstanding models and statistics, hence my questions.
Well...maybe not. See below.
From Sreten:
And from dlr:
OK, I get it. Nearly 3,000 posts later, there is fairly broad agreement that there IS a change that is audible, and Bud's "mental model" of the forces at work isn't correct. Great! Now can we move on to trying to figure out just what IS going on, and drop all the hoo-hah over Bud's theories? That might actually advance this thread.
Until that happens, I'm outta here.
Carl
PS - John K, I agree, Bud's model certainly doesn't suggest any greater significance and is probably not any more accurate. I just asked out of curiosity, since the implication I thought I heard in your post of the model was that it could be a definitive tool for evaluating EnABL. I get tired of scientists misusing and misunderstanding models and statistics, hence my questions.
I simply asked for clarification on whether you applied EnABL inside the ports.
I am sorry to have to include here, but common sense must prevail.
A port is a resonant structure that is driven by a pressure front. An acrylic dot will have so little effect that it would be very hard to measure and IMHO have no effect. Same with baffles, the wavelength is longer and to affect any wavelength to a given degree requires a given height/Z value/angular interface/position/volume/area.
EnABL may work ( i have no idea yet) but as to how it works it has to be approached with a given degree of logic and common sense.
ron
believe as John, unless there is some proof presented that the mechanism is anything other classical mechanics,
classical mechanics= my belief
I am sorry to have to include here, but common sense must prevail.
A port is a resonant structure that is driven by a pressure front. An acrylic dot will have so little effect that it would be very hard to measure and IMHO have no effect. Same with baffles, the wavelength is longer and to affect any wavelength to a given degree requires a given height/Z value/angular interface/position/volume/area.
EnABL may work ( i have no idea yet) but as to how it works it has to be approached with a given degree of logic and common sense.
ron
believe as John, unless there is some proof presented that the mechanism is anything other classical mechanics,
classical mechanics= my belief
ronc said:
What you report is interesting, but I've never been clear on what it is exactly that you are measuring or how. I'm also unclear what you mean by different axis. Perhaps you might explain in a little ore detail. I'm not an expert in laser velocimetry, but I do have some experience in the field and have been part of a research project making some pretty fancy measurements.
"Author(s): Tse, D. G. N.; Kreskovsky, J. P.; Shamroth, S. J.; Mcgrath, D. B.
Abstract: Laser velocimetry was utilized to map the velocity field in a serpentine turbine blade cooling passage at Reynolds and Rotation numbers of up to 25.000 and 0.48. These results were used to assess the combined influence of ...
NASA Center: NASA (non Center Specific)
Publication Year: 1994
Report Number: NASA-CR-4584 "
This was an interesting effort. The serpentine passage was milled from Plexiglas. The Plexiglas model was spun on the end of a 2’ radius at fairly high speed to emulate a turbine blade rotating in a jet engine. The working fluid passing through the model was a special mixture which had the same index of refraction as the Plexiglas so there was no refraction of the laser light passing through the Plexiglas/fluid interface. And of course, the control volume for the laser cross beams was focused at a point in space where the measurement point in the passage passed through on each rotation. Data acquisition had to be synchronized with the model spinning. Initially the passages had smooth walls. In later measurements the passage was “enabled”.
That is the walls were ribbed.We are using a monochromatic light source and a reciever that both are collimated and focused at a given point. The frequency is input to the driver. The cone is measured across the horiz plane. The cone is rotated 90 degrees and another measurement is made. The results are filtered to are to exclude the input frequency response.
The only problem i have had is the stepper motor noise, so i had the techs measure in between the step action. We are measuring the residual energy in the cone at different frequencies and position. Note! this position of noise moves across the cone to different positions as the frequency changes.
As stated the only pickle in the results is the difference between the X/Yscans. I can only attribute this to the varing height/mass of the dots.
ron
The only problem i have had is the stepper motor noise, so i had the techs measure in between the step action. We are measuring the residual energy in the cone at different frequencies and position. Note! this position of noise moves across the cone to different positions as the frequency changes.
As stated the only pickle in the results is the difference between the X/Yscans. I can only attribute this to the varing height/mass of the dots.
ron
ronc said:
Maybe you'd prefer I say my "position" or as you, "I am sorry to have to conclude..."? Why one would say "sorry" does escape me, I'm not sure where emotion should enter into arriving at a conclusion if objectivity is the issue. How about "the facts, yet to be contradicted, support the position..."? Would any of that change the facts as we know them? Is semantics that important to you? I suspect that you had grasped my intent, anyway.
Show me some reason to accept something else and I may change my "position". Until then, I accept hard data, the evidence we've seen, all of it supporting classical mechanics, none, nada, zilch, for anything else.
In the absence of anything to show it is not classical mechanics, maybe I should use your words, "common sense must prevail" since classical mechanics can explain and does support the data.
Dave
john k... said:
Thanks john k.
As I have said before, we are all in unexplored territory when it comes to ports and baffles.
Here are some differences in my approach:
a) I have only been able to apply the EnABL pattern at one end of the port.
b) Block materials I have used are:
- foil & double sided tape
- PVC duct tape
- sticky ends of thin, smooth plastic bandaids
I have not used acrylic blocks in ports.
c) Block sizes I use in ports are bigger than would be predicted using the 18 block pairs ideal for drivers.
For a 2" port in a BR cabinet, I would use blocks about 3mm x 1.5mm (which is closer to 10 block pairs).
d) Ports I have EnABL'd have all been front firing (excluding subwoofers).
Cheers,
Alex
G'day ron,
To me the effect of the EnABL pattern defies both logic and common sense.
Yet the audible changes are there, and so far they are all positive.
My experiments with ports and baffles have consistantly produced an audible change.
As to how these audible changes are occuring, I really have no idea.
I haven't used acrylic dots in ports or baffles so I can't comment either way.
I will include very specific details from here on with regard to future applications of EnABL pattern to ports and baffles.
Cheers,
Alex
I think if one focuses on something not entirely correct said in the past, there is not hope in moving forward.dlr said:
When you try to reduce standing wave of a specific frequency like the strong cone breakup modes, you have to design patterns specifically for that mode. Based on my experience is that this is the last resort in treating the driver. Generally if we use the patterns so that the energy in the overall spectrum can be dissipated more quickly, we can accomplish cleaner sound. Once you get cleaner sound, defficiencies at specific points will become dominating factors effecting the quality of the reproduction. If these specific points are not there in the first place, then you really have a good driver.
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