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Old 24th March 2008, 06:40 PM   #141
BudP is offline BudP  United States
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John K,
Quote:
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
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Old 24th March 2008, 06:40 PM   #142
Carlp is offline Carlp  United States
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Quote:
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
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Old 24th March 2008, 06:41 PM   #143
dlr is offline dlr  United States
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Quote:
Originally posted by Carlp

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
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Old 24th March 2008, 07:20 PM   #144
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Quote:
Originally posted by BudP
John K,


I am not certain I understand your application of this ring.
I'm not surprised.

Quote:

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.
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Old 24th March 2008, 07:30 PM   #145
BudP is offline BudP  United States
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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
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Old 24th March 2008, 07:36 PM   #146
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John, please don't try and get around the language censor.
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Old 24th March 2008, 07:55 PM   #147
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Default Re: Belief and interpretations

Quote:
Originally posted by auplater

John K.'s data looks pretty definitive.
In the absence of anything supporting the claims of change, I must agree. Thank you John.
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Old 24th March 2008, 07:55 PM   #148
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Default Excellent!

Quote:
Originally posted by Carlp


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...

John L.
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Old 24th March 2008, 08:04 PM   #149
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Default Re: No one is grasping the import of john's posts

Quote:
Originally posted by dlr


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.
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Old 24th March 2008, 08:42 PM   #150
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Default Re: Re: No one is grasping the import of john's posts

Quote:
Originally posted by ScottG


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?

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