Hey John, I hope you don't mind but it occured to me that it was a bit of an effort going back a page to compare the data sets so I'm sticking them together here for those that, like myself, are curious(and lazy!).
BTW Which driver have you shown in your tests?
FR:
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BTW Which driver have you shown in your tests?
FR:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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An externally hosted image should be here but it was not working when we last tested it.
CSD:
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An externally hosted image should be here but it was not working when we last tested it.
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An externally hosted image should be here but it was not working when we last tested it.
Thanks Dave and John.
The Baffle diffraction question is just getting more interesting, at least to those who have applied EnABL to baffle edges and actually found an audible improvement.
What does a baffle diffraction consist of, and then, what does it sound like? I ask this because it is as likely as not that what EnABL is forcing to happen at baffle edges is not relevant to all of the diffraction components.
Here is a statement I would like you to think about with respect to what portion of a baffle diffraction might be at work here.
When you put an EnABL pattern on a baffle, the immediately noticeable effect is a displacement of the entire "plane of origin", back, with a front edge seemingly at least a meter behind the baffle plate. And, that "plane of origin" becomes a volume with very distinct cues about depth of given individual elements.
Do we have a handle on what causes us to perceive depth of field and what sorts of diffraction elements contribute to that sense of origin of a sound field coming from the plane of the baffle?
I am aware that rounded corners, in the neighborhood of 2 inches in radius, are about as effective as EnABL is, with a right angle baffle edge, in respect to this depth of field perception and also the perceived point of origination of that field. Though, with a large radius edge and the EnABL'd baffle, that becomes a volume of depth rather than a plane of emission, as it is with an uncontrolled baffle with a right angle.
A baffle with a significantly smaller radius than 2 inches, perhaps 3/4 inch, can still be influenced by EnABL patterns, in the same depth sense. Even though it already has less of the specificity of a single plane of emission, than a hard edged baffle.
So, is this a time related perception? Is this very early in the reproduced event or later on?
On a slightly different tack. How large a circular baffle should I use? A 14 inch diameter gives me a 1K wavelength. Should I limit the signal to just 1 kHz and would an off axis map be of any use?
Lot's of questions, I know.
Bud
The Baffle diffraction question is just getting more interesting, at least to those who have applied EnABL to baffle edges and actually found an audible improvement.
What does a baffle diffraction consist of, and then, what does it sound like? I ask this because it is as likely as not that what EnABL is forcing to happen at baffle edges is not relevant to all of the diffraction components.
Here is a statement I would like you to think about with respect to what portion of a baffle diffraction might be at work here.
When you put an EnABL pattern on a baffle, the immediately noticeable effect is a displacement of the entire "plane of origin", back, with a front edge seemingly at least a meter behind the baffle plate. And, that "plane of origin" becomes a volume with very distinct cues about depth of given individual elements.
Do we have a handle on what causes us to perceive depth of field and what sorts of diffraction elements contribute to that sense of origin of a sound field coming from the plane of the baffle?
I am aware that rounded corners, in the neighborhood of 2 inches in radius, are about as effective as EnABL is, with a right angle baffle edge, in respect to this depth of field perception and also the perceived point of origination of that field. Though, with a large radius edge and the EnABL'd baffle, that becomes a volume of depth rather than a plane of emission, as it is with an uncontrolled baffle with a right angle.
A baffle with a significantly smaller radius than 2 inches, perhaps 3/4 inch, can still be influenced by EnABL patterns, in the same depth sense. Even though it already has less of the specificity of a single plane of emission, than a hard edged baffle.
So, is this a time related perception? Is this very early in the reproduced event or later on?
On a slightly different tack. How large a circular baffle should I use? A 14 inch diameter gives me a 1K wavelength. Should I limit the signal to just 1 kHz and would an off axis map be of any use?
Lot's of questions, I know.
Bud
ShinOBIWAN said:
No problem. I was thinking of doing it myself, but....
It’s a Vifa MG10MD09. A cute little 4" driver with glass fiber cone. The entire MG series was discontinued when DST merged with Tymphany. I don't know exactly why. The MG series was one of the best Vifa ever had. I was going to use them in the ICTA. I haven't found anything nearly as good in terms of linearity and transient response. As A result the ICTA has been delayed several times and the design approach completely changed.
BudP said:
Bud, forget it. I with draw my involvement. I don't want the drivers sent to me. DON'T SEND THEM. If you do, I accept no responsibility for returning them. Why? Because just about every post you make starts out with some BS sales pitch about who hears what and then go on to say why the laws of physics don't seem to apply in your neighborhood. Please, why don't you tell us? Please enlighten us as to how the laws of physics work in you neck of the woods. There are a lot of people living on this planet that would desperately like to leave it. Unfortunately the laws of physics as we understand them will not allow us to make the journey to what ever planet you are living on. We desperately need your help.
It is clear that if I were to continue to be involved in any driver evaluation any result that I found would be dismissed as not relevant if it did not agree with your forgone conclusions. Count me out.
john k... said:
Ouch Xmax looks very limited at 0.65 mm peak. No one expects a 4" to cover the lower octaves but even considering thats still awfully low. Apart from that it looks to be a nice driver for mids.
http://www.madisound.com/catalog/product_info.php?products_id=1116
dlr said:
Hi Dave, Tell me if I'm missing something, but don't panels vibrate modally because the sound waves in the panel reflect from the impedance boundary at the edge? No reflection, no energy storage, no mode? Whether modes are created due to speaker mounting or interior resonances isn't directly relevant, I think.
So if damping is placed near the edge, would it not damp the sound waves? Placed right on the edge is obviously not a good idea (zero velocity) but a bit away from it would damp higher velocity waves. Seems to me higher frequencies would be damp-able.
Damping those waves gives less energetic modes. No?
If the damping is in the right place, how much is actually needed? A reasonably distributed pattern might be effective for some frequencies.
Not true John. I have not discounted any negative experience, even those caused by what I consider a misapplication of the patterns.
No one knows how you will respond to the A/B comparison and you are not required to respond in a particular fashion. It just seemed the only way to allow you to subjectively evaluate whether or not you thought the changes you could hear, assuming you did, were reflected in the CSD tests you put up on your web site. Personally I think they are clearly shown there, but I do not have a wealth of experience with test results and using them to track down changes in driver behavior.
As for the baffle diffraction. I really am curious to find out why I have the experiences with them I do, and why others report the same results, in an anecdotal fashion. Both you and Dave were kind enough to inform me where to start, to see if I can find a shred of evidence of alterations. I intend to pursue the course suggested, At least, due to both of you, I have some idea of what scale of change I am looking for.
To me this is different from the baffle questions I have and I had no intention of involving you in that beyond asking how to get the nuts and bolts at least aimed in a useful direction for testing. You have provided that and I appreciate your information and will use it. If I find anything you will know about it. If I find nothing you will know about that too.
Will you please reconsider?
Bud
FrankWW said:
Consider this. It there were any damping or modification to the vibration characteristics, then the same principle should apply to room modes and wall vibrations. A room is just a big, relatively unbraced box. All I would need to do to control those pesky, 20,30,40,60Hz or whatever room modes impinging on the walls and any frequencies related to unbraced walls is to enable all edges (corners) of the walls (appropriate size and pattern, of course). If it works for box panel vibrations, it must therefore work in all like situations.
I know what I think of this.
Dave
FrankWW said:
Why not do some calculations and determine what the degree of this proposed effect might be. Could make a stronger argument, don't you think?
The term "grasping at straws" comes to mind here. Lots of "what if's", "perhaps", "maybe this is happening' ad nauseum. Why not apply the so called damping at the maximum? That should have even more effect,no?
John L.
I came from a perspective of scepticism with regard to EnABL and its effects.
Your dismissal of EnABL’d baffles may well be on the basis of ‘known science’ but is inconsistent with good scientific investigation.
It’s like arguing - “The well known scientific fact is that the world is flat. Therefore, we don’t need to sail to the edge of the earth because we already know the outcome.”
Thankfully, Christopher Columbus was prepared to test ‘known scientific facts’.
I have heard an EnABL’d baffle - yourself, dlr and others have not.
My only claim with EnABL on baffles is that there is an audible effect that is able heard by others who have listened.
As to why there is an audible difference when on baffles I offer no explanation – diffraction or otherwise.
I think there is more to EnABL than simply ‘added mass’.
The laws of physics as we understand them do not allow for the possibility of any effect of EnABL on baffles.
And yet there IS an audible effect that is observable and repeatable.
why can't someone defending enabl do a blind test. just invite some people, don't tell what you are testing (very important, coolest looking speaker will always win) . put a few pairs of speakers in front of them, not telling which one is playing and let them pick sound that they like most.
MisterTwister,
We were hoping SY was still going to do that. He did declare an intent to do so, but life does change your mind for you pretty often and we haven't heard from him in a few hundred posts.
The four raw Fe 127's are on their way to me. Perhaps I will put a low visibility pattern on them, as I did for the Lowther PM6A demo at RMAF.
Unfortunately that test has been set aside by skeptics, because folks who went might have gone to hear a difference. So, your observation is a good one.
Also, unfortunately, anything I do is also immediately suspect, so any test I might run will also be set aside. I don't have a problem with this, but if the skeptics won't even listen to them they aren't likely to do the tests either.
Cilla, if you are listening, do you know enough housewives in England that you could set up a test? By now, that may be one of the few groups that would not be pre biased, by contact with this thread.
Bud
We were hoping SY was still going to do that. He did declare an intent to do so, but life does change your mind for you pretty often and we haven't heard from him in a few hundred posts.
The four raw Fe 127's are on their way to me. Perhaps I will put a low visibility pattern on them, as I did for the Lowther PM6A demo at RMAF.
Unfortunately that test has been set aside by skeptics, because folks who went might have gone to hear a difference. So, your observation is a good one.
Also, unfortunately, anything I do is also immediately suspect, so any test I might run will also be set aside. I don't have a problem with this, but if the skeptics won't even listen to them they aren't likely to do the tests either.
Cilla, if you are listening, do you know enough housewives in England that you could set up a test? By now, that may be one of the few groups that would not be pre biased, by contact with this thread.
Bud
dlr said:
I know what I think about it, also.
For 20 - 60 Hz and so forth, the widget is called a bass trap. It's a matter of scale isn't it?
I did think about bass traps as a sort of model. You put them away from the wall so as to catch waves of interest at some velocity. At the wall is maximum pressure, zero velocity.
Last I looked, a bass trap is a pretty skinny thing compared to the length of the wave it's supposed to trap. Often they're not effective enough because there's not enough coverage - lots of energy in those long wavelengths. Not the same with high frequencies.
With shorter wavelengths, on the other hand, it's extremely easy to over damp a room long before the walls are all covered up.
My point is that a bunch of reasonable people did something and reported what they heard of a better than just noticeable difference. I'm not saying that what they did in this case is optimum or most desirable way of doing things; what I am saying is that there is a possible way of explaining what happened without doing any violence to physics. And it doesn't require armchair psychologizing about placebos.
John L,
One gets access to maximum velocities all around the panel's periphery but not at the periphery.
I'm really bad at math and it's horribly time consuming for me. It's something I want to do, though. Maybe next week I'll get something done and you can have lots of fun digging out the inevitable mistakes - just too busy for anything more this week.
(Personally, if I had a plywood or MDF speaker panel radiating grunge, I'd stick a really thin sheet of aluminum (like what they use for rain gutters) to the whole thing with some permanently tacky adhesive. That's what I'd do. That takes care of maxima and minima and I don't have to calculate zip.)
dlr,
Doesn't that I know of. Just disperses the lobes that I used to be familiar with, before I started applying it, some distance back from a sharp edge, or the beginning of a round over. Also displaces the perceived location, for the generation of the sound, back behind the speaker, in a volume rather than as specifically arising from the baffle plate. I don't see how EnABL patterns could provide any attenuation to energy ringing in the panel, unless maybe they were divots filled with damping goo.
This is why I asked earlier what was considered baffle diffraction. What the various components were, that had been lumped in the category.
Bud
Doesn't that I know of. Just disperses the lobes that I used to be familiar with, before I started applying it, some distance back from a sharp edge, or the beginning of a round over. Also displaces the perceived location, for the generation of the sound, back behind the speaker, in a volume rather than as specifically arising from the baffle plate. I don't see how EnABL patterns could provide any attenuation to energy ringing in the panel, unless maybe they were divots filled with damping goo.
This is why I asked earlier what was considered baffle diffraction. What the various components were, that had been lumped in the category.
Bud
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