EnABL - Technical discussion

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John K,
White and orange are with and without the Enable like ring.

I am not certain I understand your application of this ring. Is this a contiguous ring or was it made up of block sets? What was the diameter that caused you to arrive at the particular width used?

The size of blocks applied to a baffle do correspond to the peripheral dimensions of that surface. In a subjective sense, these patterned block sets have very little effect when applied at locations away from the baffle edge. At most, when applied around two drivers, a slightly closer location for the blending distance in free air is noticed.

Bud
 
Two possible outcomes

- makes a difference (+) (reject null hypothesis, makes a difference)

- Does not make a difference (-) (do not reject the null hypothesis, no difference)

Not quite, John L. If you reject the null hypothesis, you can largely say it makes a difference. On the other hand, if you can't reject the null hypothesis, you can't really say there's no difference. Just that you can't reject chance as the cause of any difference that's found. There's a big difference. Too many people misunderstand statistics.

Carl
 
Carlp said:

Dave, not really disingenuous - more like cheeky, trying to bring some levity. Note the smilie wink! Plus, I didn't say anyone said NOTHING happens, just virtually nothing (relative to audibility), but maybe I've misunderstood what some people are saying. Is everyone saying there IS or COULD BE a dramatic change due to EnABL?

Carl

Sorry, my mistake, I took the tone wrong. As if that was the first time!

I would refer you to the bulk of the original thread on the latter question. Certain contributors should stand out as to how emphatic they are. Which category they fall into ought to be obvious as well.

Dave
 
BudP said:
John K,


I am not certain I understand your application of this ring.

I'm not surprised.

At most, when applied around two drivers, a slightly closer location for the blending distance in free air is noticed.

Bud

Sure, and you've documented that, what ever it means, I'm sure.

Let me tell you how it's doing to be. This is a technical thread. I'm not going to response to much of anything, just present the results of carefully performed experiments with my interpretation of them and allow other to come to there own conclusions. I'm not going to engage in speculation, or respond to it. I'm not going to get in a ****ing contest with you and you distortions. I'm not going to response to the three musketeers, M, M and M... Misdirect, Misrepresent and Misinform.

What we have here is clear evidence that when an acoustic wave in the aduible frequency range encountes a surface perturbation with width and height on the order an enable patch applied to a driver the acoustic wave passes over it unaltered. This experiment was never really about edge diffraction. It was about isolating the effect of the patch as the wave passes over it.
 
Excellent!

Carlp said:


Not quite, John L. If you reject the null hypothesis, you can largely say it makes a difference. On the other hand, if you can't reject the null hypothesis, you can't really say there's no difference. Just that you can't reject chance as the cause of any difference that's found. There's a big difference. Too many people misunderstand statistics.

Carl

You picked up on it! Someone is actually paying attention... at least we're starting to talk about test methods.

You're right, of course... chance is the key here....:)

Lots of people have claimed boundary layer is the cause. The name itself is an acronym for said explanation. Read back early posts...

Maybe a new acronym like E.I.E.I.O. for Enhanced Inferred Effects of Interference on Objects...:D ;)

John L.
 
Re: No one is grasping the import of john's posts

dlr said:


This may be the cause of one of the primary differences in perception. It is still, though, simply a change in the frequency response as either a mic or the would detect at some nominal distance x from the driver. That is, it's the integrated output of the driver on that axis. The change, whatever it is and however it occurred, is without doubt measurable, as has been made clear a number of times. We know this to be a fact.

Are we going to go back to pure speculation on something that no one involved in this thread has the resources to determine, but has been shown (by john, again) to be without support through analysis of the physics? How about a bit more focus on that which we do know and that shows direct support for the classical mechanics (oops, sorry, there's another inadvertent hint).

Dave

I think that "simply a change in the frequency response as a mic would detect at some nominal distance x from the driver" - is to simple. While our ears may pick up the sound in this fashion, it IS not only a combination of dual horizontally opposed "mic's" (aka ears), but also an overlay of pinna cues - and *massive* processing by the brain. Even from the most basic perspective then we don't simply hear a discreet "axis". In fact, depending on the degree of rotation, our ability to hear horizontal "dispersion" is nearly as good as our ability to hear the primary axis. In this instance then it would need to be more than one measurement, and NOT an average of multiple displaced measurements.

Of course none of this is to say though that there won't be some change in linearity, and I fully agree that such a change is measurable.

IMO then the next "steps" in the question process are:

1. (In context with the above..) Have we done enough measuring to determine if there is a change?

and,

2. If there is a change, will we be able to perceive it as being relevant?


"1" is bad enough, but "2" can sometimes be incredibly illusive. The best analogy I can think of here are from people that have played with turning their own (solid-block) conical horns. (..and again, its a matter of upper freq. response.) Same flare, same driver, same system - DIFFERENT MATERIAL. Measured difference even at most axis's - seemingly negligible, but perceived differences were not. The measured data's there to say *something* is different, but its "weight" to form a conclusion is MIA.
 
Re: Re: No one is grasping the import of john's posts

ScottG said:


While our ears may pick up the sound in this fashion, it IS not only a combination of dual horizontally opposed "mic's" (aka ears), but also an overlay of pinna cues - and *massive* processing by the brain. Even from the most basic perspective then we don't simply hear a discreet "axis". In fact, depending on the degree of rotation, our ability to hear horizontal "dispersion" is nearly as good as our ability to hear the primary axis.


I don't know if anyone has attempted to plot the polar pattern of human hearing. If so, I would assume that it is in fact cardioid shaped, which would then allow the brain to determine whether a sound is directly to the side of you, in front of you, or in back of you, due to time vs amplitude roll off's of the cardioid pattern.

If the EnABL treatment shows up as doing more to the off axis sound than the on axis sound (which I can't fathom it doing), it will show up when measured with a microphone. There's no doubt in my mind. Condensor microphones are extremely sensitive. I mean, look at JohnK's overlays of 2 successive tests.

On the topic of EnABL'd baffles. I don't feel that the BL theory is valid. In my limited understanding of fluid dynamics, wouldn't there need to be a certain amount laminar flow before the appearance of a boundary layer?

If EnABL were affecting the BL of the wave moving across the baffle, would then the EnABL pattern blocks actually be causing turbulence (due to vortices or eddy currents) and actually be causing "distortion"?

It does seem to me that at the height of the EnABL blocks, and given the (in context) low frequencies and velocities, that the blocks can't possibly have any noticeable effect. They're just too "invisible" to a boundary layer effect.

Comments?

Am I visualizing that correctly?

Cheers
 
Re: Re: No one is grasping the import of john's posts

First, let's be sure that we don't lump everything together. There's the application to drivers that have moving mass and the application to immobile surfaces, two entirely different considerations.

ScottG said:


I think that "simply a change in the frequency response as a mic would detect at some nominal distance x from the driver" - is to simple. While our ears may pick up the sound in this fashion, it IS not only a combination of dual horizontally opposed "mic's" (aka ears), but also an overlay of pinna cues - and *massive* processing by the brain. Even from the most basic perspective then we don't simply hear a discreet "axis". In fact, depending on the degree of rotation, our ability to hear horizontal "dispersion" is nearly as good as our ability to hear the primary axis. In this instance then it would need to be more than one measurement, and NOT an average of multiple displaced measurements.

It's not too simple. If there is a change, a mic will detect a frequency response change better than the ear can, though I agree that it takes a set of measurements of one desires to make a correlation between measurements and perception. You've made the point that I have since day one. But interpretation as to the perceptual nature doesn't matter at our level of discussion. If there is a change large enough to be detectable by ear (proof of which is extremely difficult at times), the perception of that change is irrelevant to the core of the discussion.

And now, note that the purely subjective side is not supposed to be in this thread. They split it off.


Of course none of this is to say though that there won't be some change in linearity, and I fully agree that such a change is measurable.

IMO then the next "steps" in the question process are:

1. (In context with the above..) Have we done enough measuring to determine if there is a change?

With regard to drivers, from day one I don't think that there's been any disagreement. There is a change, it's easily measured (though that took time to achieve consensus). The debate focused on why (mechanism). I think that john k's answered that one definitively.

As to immobile surfaces, until John post his hard data, it's all been subjective opinion, except for those of us who've spent years measuring and studying diffraction. At some point is becomes useless to measure for what is obviously futile. John's data confirms that position.


2. If there is a change, will we be able to perceive it as being relevant?

Again, the two different considerations must be addressed separately and this question is more appropriately in the other thread. There's too much lumping of them together. But your last question is relevant in both cases, though I think that there's agreement that the changed FR in drivers is real and relevant, whether considered good or bad. As a tweak to a driver it certainly does make a change. Good or bad, that's up to each individual, none of us has contested any preferences on that.

Dave
 
BudP said:
Jon K,

And I was asking politely what the EnABL patch was comprised of? Is it a single solid ring, is it two solid rings or is it an actual EnABL pattern?

Bud


I'm no longer interested in being polite. I'm only interested in data and facts. My description of what I did was quite clear, as is the result. A patch the size of an enable patch on any surface has no impact on the propagation of an acoustic wave in the audible frequency range as it passes over the patch. I'm am no longer interests in verbal jousting.

I remain open minded to the reported observations that a positive change may occur for drivers. But I am not interested in entertaining speculation. There was too much of that in the old thread. So excuse me for being curt.


Cal Weldon said:
:cop:

John, please don't try and get around the language censor.

Sorry Cal. But p:censored:contest is a technically accepted term. :) I din't think it worthy of censorship. :cannotbe:

But I take it to heart.
 
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Re: No one is grasping the import of john's posts

dlr said:
It is interesting that for those in this thread who are doing any current mods to drivers in their own, personal systems, all mods are being done on full-range drivers.

Some people use these up to 2k, personaly i start feeling uncomfortable when things start creeping up over 500 Hz.

dave
 

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Re: Re: No one is grasping the import of john's posts

planet10 said:


Some people use these up to 2k, personaly i start feeling uncomfortable when things start creeping up over 500 Hz.

dave

I would be very interested in before/after measurements raw, then the same with a crossover in place. Got any to show? I'm especially interested in the response with a crossover, since that's how it will be used. If the Fc is 500Hz, changes are likely to be rather far down in level, I'd like to see just how much is changed and how far down it is before/after.

So how about your analysis of John's posted data? So far no one has made an attempt. You've got a modded driver to show, but you leave John's post without response. There's a lot of expressed interest in objective data, yet no one discusses it once it's made and posted. How about you?


John's post

Dave
 
I'm only interested in data and facts. My description of what I did was quite clear, as is the result. A patch the size of an enable patch on any surface has no impact on the propagation of an acoustic wave in the audible frequency range as it passes over the patch.

I agree. On my initial tests i keep seeing the same results. I truly dont believe its a BL affected condition but more of a slight change in mass at a given point that disrupts ,or partially disrupts, the induced low level energies that are moving across the cone surface.
Note! i am still unbiased.

ron
 
Re: Belief and interpretations

auplater said:


Seems to me there are certain belief systems evidently occurring here that are not going to accept factual data unless supportive of the presumptive improvements being touted.

No amount of empirical data will be deemed adequate to sway such beliefs. That's too bad.

John K.'s data looks pretty definitive.

John L.
I just think it weird not to show the diffraction impulse difference but rather use an indirect method to try and conclude what will happen to the diffraction impulse.:confused:
 
I truly hate getting into metaphysics here.
Take anybody in the world who can drive. Give them a Yugo to drive and then let them drive a Porshe 930 turbo to drive. Ask them to define the difference. The difference they describe is subjective. They cant describe the actual physics of the difference. All we (or i) want to do is define the actual physics.

ron
 
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