Nordic said:
Rope caulk - the brand 'Mortite' - also does wonders for driver baskets IME
Here's lots of it -
An externally hosted image should be here but it was not working when we last tested it.
Off Topic
Sorry for going off-topic...
This whole thread saw alot of wonderful people in different domains. Now since EnABL is kinda a cone "mod", I'm just making a list of guys here at DIYaudio who can "mod" cones with success.
MarkMcK
john k...
soongsc
BudP (still controversial to me, but worthwhile to make the list for sure)
Who could I add to this list ?
Sorry for going off-topic...
This whole thread saw alot of wonderful people in different domains. Now since EnABL is kinda a cone "mod", I'm just making a list of guys here at DIYaudio who can "mod" cones with success.
MarkMcK
john k...
soongsc
BudP (still controversial to me, but worthwhile to make the list for sure)
Who could I add to this list ?
Magnetar said:Sure looks prettier then stock or 'enable' - How big were the dots? Maybe small dabs of silicon glue would be similar but permanent. I can see a drum roll coming on and little dots of mortite being propelled at me
The decay is generally faster with the mortite 1, with the exception of the ~2khz to ~7khz area, which may turn out to be the more critical impact area as far as music and imaing benefits.
Also, in this same area, the enable decay is considerably flatter and smoother, with more regularly spaced lines, though I'm not sure how that would tranlate into music. Perhaps this is reflective of the "increased information" that many have witnessed.
I'll try to answer all the questions here.
1) Mortite patterns. a) I tried an enable like patterns and saw now significant differences form acrylic. b) The remainder were just random placement, but the more successful were when the applications were more or less at about 1/2 the cone radius as opposed to near the VC or surround. This would be contrary to the Enable approach.
2) The Mortite dabs were between 1/8" and 1/4" in diameter. maybe 1/64" or less thick (more of less). Some bigger, some smaller.
3) Placing the dabs on the back of the cone seemed to have the same qualitative effect. I believe this discounts any consideration of any fluid dynamics boundary layer playing a roll as any BL on the front side would be unaltered. The concept of a fluids BL didn't make much sense to me from the start.
4) Mortite, like modeling clay. As mentioned, it's a brand name. Originally used as a weather stripping when, for example, installing aluminum storm windows.
Dick Sequerra used to do this type of thing back in the '70s with some of his Metronome speakers. Specifically on the Met III speakers I auditioned at the time. I wrote to him about poor midrange clarity on the Met IIIs I listened to. Next thing I knew I got a letter from him inviting me to audition the speakers again at the same dealer. When I went to the 2nd audition this treatment was visible on the mid cones. Unfortunately it didn't solve the problem. While the speakers did sound different the mids were still unacceptably clouded.
My personnel opinion of all this is that if you want better damping then maybe you should be looking at cones with higher internal damping. The old Polyprop, Bexterene and Aerogel cones come to mind. It seems the pendulum swings in audio. Cones with high internal damping don't seem to be so popular today. Supper rigid cones are more accepted. Maybe the pendulum is about to swing back the other way. Ofcourse, I doubt there will be any full range drivers that don't use fairly rigid cones.
1) Mortite patterns. a) I tried an enable like patterns and saw now significant differences form acrylic. b) The remainder were just random placement, but the more successful were when the applications were more or less at about 1/2 the cone radius as opposed to near the VC or surround. This would be contrary to the Enable approach.
2) The Mortite dabs were between 1/8" and 1/4" in diameter. maybe 1/64" or less thick (more of less). Some bigger, some smaller.
3) Placing the dabs on the back of the cone seemed to have the same qualitative effect. I believe this discounts any consideration of any fluid dynamics boundary layer playing a roll as any BL on the front side would be unaltered. The concept of a fluids BL didn't make much sense to me from the start.
4) Mortite, like modeling clay. As mentioned, it's a brand name. Originally used as a weather stripping when, for example, installing aluminum storm windows.
Dick Sequerra used to do this type of thing back in the '70s with some of his Metronome speakers. Specifically on the Met III speakers I auditioned at the time. I wrote to him about poor midrange clarity on the Met IIIs I listened to. Next thing I knew I got a letter from him inviting me to audition the speakers again at the same dealer. When I went to the 2nd audition this treatment was visible on the mid cones. Unfortunately it didn't solve the problem. While the speakers did sound different the mids were still unacceptably clouded.
My personnel opinion of all this is that if you want better damping then maybe you should be looking at cones with higher internal damping. The old Polyprop, Bexterene and Aerogel cones come to mind. It seems the pendulum swings in audio. Cones with high internal damping don't seem to be so popular today. Supper rigid cones are more accepted. Maybe the pendulum is about to swing back the other way. Ofcourse, I doubt there will be any full range drivers that don't use fairly rigid cones.
John K,
Obviously I don't agree with that assessment about BL effects.
However the reciprocity from front to back is well known and used in the EnABL process. One of the problems inherent in EnABL pattern treating both sides of a cone is the increased transparency to reflected sounds exiting into the front load space, as coherent information, rather than the usual noise with little information content. This is one of the reasons I was and still am interested in the Mamboni process.
That a backside treatment affects the front side only shows that the transverse wave is being attenuated and attenuation on one side is going to attenuate the other, emitting side also. This shows nothing about boundary layer events. Ohm used the same sort of attenuation of one side, to both slow down the wave propagation speed and control resonances of their pure bending wave drivers, the Ohm F and A.
Vifa has long used a direct application of attenuation material, on the emitter side of interest and EnaBL is just as effective on those drivers, as it is on uncoated or internally damped polypropylene diaphragms.
Please keep in mind that we are looking a bit further than random "improvements" to FR or CSD. EnABL is not claimed to provide alterations in those commonly tested events. It obviously does some of this work and it is also obviously tied to it's distributed mass, tiny as that actually is. The real importance of EnABL is in coherency of information, that comes from the drivers.
I guarantee you that EnABL would have cleared up the information content of that Metronome driver, in a very significant fashion.
On the EnABL pattern, did you apply the pattern to both edges for these tests? Not a quibble, just a query, as I used to apply the pattern only on the terminus edge, rather than to both diaphragm edges.
When looking at the clean to EnABL I notice that, above the resonant peaks, that EnABL is specifically not supposed to alter or at least it wasn't until Soongsc showed it could, I see a quicker dispersal of the resonances above those main peaks. I see a quicker loss of energy and less adjacent frequency bleed, within the main peaks and, the already noted by dineubec, smoother and faster energy shed in portions of the FR below the peaks.
If this were an applied signal, with an information content that was supposed to be similar in shape to the initially expressed FR plot at time zero, rather than a flat line, I would have to say that the EnABL 'd driver would be considerably less confused in it's presentation.
I still emphatically agree with your earlier comment about random application of undirected measures for control of diaphragms. I also applaud your experiments into this zone of the unknown. So far, I think EnABL is more than holding it's own, even in this sort of random emitted energy test. Random only in that the signal does not exhibit an information content, which is the basis of the subjective EnABL "improvements.
I hope you push further here and continue to explore.
Bud
Obviously I don't agree with that assessment about BL effects.
However the reciprocity from front to back is well known and used in the EnABL process. One of the problems inherent in EnABL pattern treating both sides of a cone is the increased transparency to reflected sounds exiting into the front load space, as coherent information, rather than the usual noise with little information content. This is one of the reasons I was and still am interested in the Mamboni process.
That a backside treatment affects the front side only shows that the transverse wave is being attenuated and attenuation on one side is going to attenuate the other, emitting side also. This shows nothing about boundary layer events. Ohm used the same sort of attenuation of one side, to both slow down the wave propagation speed and control resonances of their pure bending wave drivers, the Ohm F and A.
Vifa has long used a direct application of attenuation material, on the emitter side of interest and EnaBL is just as effective on those drivers, as it is on uncoated or internally damped polypropylene diaphragms.
Please keep in mind that we are looking a bit further than random "improvements" to FR or CSD. EnABL is not claimed to provide alterations in those commonly tested events. It obviously does some of this work and it is also obviously tied to it's distributed mass, tiny as that actually is. The real importance of EnABL is in coherency of information, that comes from the drivers.
I guarantee you that EnABL would have cleared up the information content of that Metronome driver, in a very significant fashion.
On the EnABL pattern, did you apply the pattern to both edges for these tests? Not a quibble, just a query, as I used to apply the pattern only on the terminus edge, rather than to both diaphragm edges.
When looking at the clean to EnABL I notice that, above the resonant peaks, that EnABL is specifically not supposed to alter or at least it wasn't until Soongsc showed it could, I see a quicker dispersal of the resonances above those main peaks. I see a quicker loss of energy and less adjacent frequency bleed, within the main peaks and, the already noted by dineubec, smoother and faster energy shed in portions of the FR below the peaks.
If this were an applied signal, with an information content that was supposed to be similar in shape to the initially expressed FR plot at time zero, rather than a flat line, I would have to say that the EnABL 'd driver would be considerably less confused in it's presentation.
I still emphatically agree with your earlier comment about random application of undirected measures for control of diaphragms. I also applaud your experiments into this zone of the unknown. So far, I think EnABL is more than holding it's own, even in this sort of random emitted energy test. Random only in that the signal does not exhibit an information content, which is the basis of the subjective EnABL "improvements.
I hope you push further here and continue to explore.
Bud
John K,
I beg your pardon John, my question on which EnABL patterns were applied where was already answered.
OT
Would you, or some other savvy soul, please provide a short tutorial on how to place these plots in Javaa Script, for we who are illiterate and itinerant single finger typists and indifferently skilled mice herders? Please?
Thanks,
Bud
I beg your pardon John, my question on which EnABL patterns were applied where was already answered.
OT
Would you, or some other savvy soul, please provide a short tutorial on how to place these plots in Javaa Script, for we who are illiterate and itinerant single finger typists and indifferently skilled mice herders? Please?
Thanks,
Bud
BudP said:
Fair enough, but my experience if theoretical and experimental fluid dynamics is quite to the contrary. There simple isn't any physical, fluid mechanical process which could have any such effect over the length scales involved.
Actually, based on the discussion previously presented it has a lot to do with BL effects. Previously statements were made, and supported by you, that the Enable process "lifts" the surface wave outside the BL and this has some resultant contribution to what is going on. But if there is no enable pattern on the front surface then there is nothing to lift the surface wave out of the BL, yada, yada, yada....
Having owned Ohm F's, and have the drivers exchanged 3 times by the factory, and even having an Ohm rep at my home on one occasion to see if he could determine the source of the problem I was having, I am well versed in the design of the Ohm A and F, and the failure there of.
We'll never know, will we?
Bud, please! I'm a research scientist (or was before I retired). I did tests with the pattern applied only at the outer edge and with the full treatment, full meaning near the surround and around the VC/cone junction. I tried to match the pattern posted some time ago in a pdf file. Probable wasn't perfect, but as good as would be expected form the average DIYer.
John k, how would you sum up the results of your findings of this process? I keep following this thread and would like your overall summation strictly from the science.
I respect all of the subjective responses and consider this process something that can produce a difference in what we hear. I would like to compare a treated driver to a non treated one if the opportunity arises to determine if I can appreciate the difference made.
On another note, I really enjoy the sound of my Fostex 165k even tho in one of your comparison tests you did not like it. But I did like your review and appreciate your time and effort logging your results.
http://www.zillaspeak.com/bib-godzillabib.asp
Godzilla
I respect all of the subjective responses and consider this process something that can produce a difference in what we hear. I would like to compare a treated driver to a non treated one if the opportunity arises to determine if I can appreciate the difference made.
On another note, I really enjoy the sound of my Fostex 165k even tho in one of your comparison tests you did not like it. But I did like your review and appreciate your time and effort logging your results.
http://www.zillaspeak.com/bib-godzillabib.asp
Godzilla
One thing to keep in mind that has been absent in this thread is that if one is going to compare a treated driver against a non-treated driver for whatever treatment is under consideration, both of those drivers must be shown to be very, very close in response prior to one being modified. The differences between two raw drivers must be considered as a possible influence and taken into account.
Variability in drivers is not an insignificant issue, even in those of high quality. The verification cannot be done strictly using purely the on-axis response either, because much of our perception is based on everything we hear that includes the power response, that is, the influence of the off-axis response of the driver. I suspect that full-range drivers have more variability in the off-axis between drivers.
Dave
On aluminum cones, the EnABL pattern needs to be optimized. If you are using the original way of laying out, then it will not have so much effect. I have mentioned this very early in this thread.john k... said:
Whether placing any pattern have the same effect depends on the shape of the cone and the amount of damping material. I discovered this proabaly two years ago when I did some tests in the from and asked the factory to do it on the back. The results were significantly different. With a large cone and the small amount of mortite you use, it may have no difference.
You driver response does not allow the effects of the boundary layer to be significant as I have already addressed, and which is due to the way the your driver uses the cone resonance to reach the higer frequencies. If you want to see the boundary layer effect, probably a different driver should be used.
If you are using a commercially available driver, I'm sure many people would like to know which make and model it is.
Ted Jordan had appropriately addressed the principles and effects of cone shapes and material openly in Wireless World. Most cone material losses much detail because of the internal loss. Metal cones allow you to hear more detail, but the cone resonances need to be controlled. The key is good damping without loss of the onset detail transients.
There are many ways to find more effective treatement.
One is FEM analysis based using the appropriate material qualites during the analysis. I would normally prefer this way if I could.
Next is a rough educated/calculated guess, and then some small adjustements as tests are conducted. I normally take this approach.
Then one could also just to a series of pattern shifts to try and discover some trends to find the right pattern. Time consuming, but still rewarding.
One is FEM analysis based using the appropriate material qualites during the analysis. I would normally prefer this way if I could.
Next is a rough educated/calculated guess, and then some small adjustements as tests are conducted. I normally take this approach.
Then one could also just to a series of pattern shifts to try and discover some trends to find the right pattern. Time consuming, but still rewarding.
Bud, please! I'm a research scientist
All i am is an engineer, a PE with over 40 years experience. In your evaluation John, i would have no worthwhile input.(its obvious)
Please dont live on what you did , but what you can do in a pratical , applical sense. Otherwise its nothing more than ego.
ron
All i am is an engineer, a PE with over 40 years experience. In your evaluation John, i would have no worthwhile input.(its obvious)
Please dont live on what you did , but what you can do in a pratical , applical sense. Otherwise its nothing more than ego.
ron
soongsc said:
Well my position on BL effects is the same as on the added mass effect. Before I will, or anyone should accept that BL effects are part of the problem ask what the possible effects could be and then see if it is reasonable to assume that they would be of a magnitude to affect a change. So the first thing to ask is what is a BL? The simplest answer is it is a thin layer near the surface where the effect of viscosity and heat conduction alter the behavior from that of an ideal, frictionless fluid to a real fluid. In simple terms this means we go from a situation from where the fluid partial velocity parallel to the radiating surface goes from a full slip condition to a no slip condition. Since we know that the fluid partial velocities will be very small compared to the speed of sound, even with large cone excursion, and since we know that viscous effects in air at audible frequencies are purely dissipative, then we are left with the observations that consideration of viscous effect will not change the speed of propagation of acoustic waves for this problem and over the length scales of the possible BL thickness there can be no significant dissipation. Thus consideration of BL effects seems inappropriate for this problem and, furthermore, it isn't BL effects that would be relevant, it is changes in the BL effects due to the application of the surface treatment.
Like I said in my response to ronc, I'm not a sheep. I'm not going to accept the BL physics as significant just because someone says so. I'll consider any arguments, but they would have to be a lot more than hand waving. Show me some hard evidence or alt least provide a counter argument that has some basis in physics.
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