Walsh termination
Just in case you folks would like to step outside of the normal mass loaded cone termination regimen, please read this.
http://www.positive-feedback.com/Issue21/standingwaves.htm
The entire process was developed on a pair of Ohm F's and turned them into point source radiators, in a spherical sense. Also eliminated the reflections from the materials joints.
Bud
Just in case you folks would like to step outside of the normal mass loaded cone termination regimen, please read this.
http://www.positive-feedback.com/Issue21/standingwaves.htm
The entire process was developed on a pair of Ohm F's and turned them into point source radiators, in a spherical sense. Also eliminated the reflections from the materials joints.
Bud
Hi Bud
Any idea on how the pattern was applied and what material was used? Conformal coating should not be a big problem but gluing on all of those little squares is really going to take some time!!
How in the world did they do it?
Could not find any other development of the concept - did / has anyone employed the design?
Interesting idea (the pattern) - but I think that mamboni has allowed for this with his design of the felt pads applied to the cone material - but he is the one to pose an answer to that question. His design looks doable in the DIY sort of way - so I'm headed that way 1st.
But the science looks very interesting! I can feel my mental gears turning - but then there is a lot of rust there!
Any idea on how the pattern was applied and what material was used? Conformal coating should not be a big problem but gluing on all of those little squares is really going to take some time!!
How in the world did they do it?
Could not find any other development of the concept - did / has anyone employed the design?
Interesting idea (the pattern) - but I think that mamboni has allowed for this with his design of the felt pads applied to the cone material - but he is the one to pose an answer to that question. His design looks doable in the DIY sort of way - so I'm headed that way 1st.
But the science looks very interesting! I can feel my mental gears turning - but then there is a lot of rust there!
Secrets revealed
Crank up the WD 40 machine... here we go.
The first thing done was to remove all of the internal foam damping material. Second was to "letter" this block pattern , on the inside, using a flat acrylic model paint, right out of the bottle . This paint was applied directly to the titanium surface, aluminum surface and the bottom edge of the paper using Speed Ball A series, 1 to 5, calligraphy pens (the ones with a bent tip). The pattern template is supplied by printing on a sheet of paper, with printing and scaling provided by Corel Draw 4 or later. Cut the round pattern out, apply it to a thin cardboard stiffener and you are ready to "letter". The scaled pattern needs to be a bit smaller than a direct size, so it settles deeper into the top of the cone than where you are going to apply the pattern. This pattern application location is the bottom edge of each material stage. The same process is applied to the outer surfaces, in the same places, though moved up a bit due to the glue overlap. In this case the ring printed by Corel needs to have the center cut out and it needs to be slightly larger than the applied pattern so that it will sink towards the bottom, underneath where the pattern is to be lettered.
The pattern does not need to be particularly precise so skill needs are rudimentary and if you can hold a calligraphy pen you can perform the needed activity. Best to learn on cheap paper speakers first. And, you will be amazed by how good these things really are.
Application of the conformal coating, on metal surfaces is only over the pattern, not the entire metal surfaces. For the paper you can apply it over all of the cone material, for much deeper bass as it will stiffen the paper, or just over the pattern for what has always been available.
Since this process adds mass only on the transverse wave boundary layer, the amount of mass needed is infinitesimal compared to what is needed to mass damp the entire driver surface. This is true regardless of materials or frequencies being controlled and works as well in infrasonic as it does in ultrasonic, though the pattern is comprised of really tiny blocks of printed material in the ultrasonic realm.
To experiment with dome tweeters and other small radiators you will need to acquire a range of technical lettering pens from the days of yore when mechanical drawings were done by hand on vellum paper. Since this is a scalar architecture, with the same number of blocks for any given ring diameter you will need some pretty fine points and to cut the acrylic paint with water by 10% or so.
Yes, I am the mad fool who developed this, so I can provide you with a Corel file should you be interested in experimentation.
The claims I can make are quite extensive but the one that I really like the benefits of the most are the resulting infinite resolution of micro dynamic signals and the addition of many dB of headroom before compression sets in. All of the information revealed by the process has always been there, just unintelligibly presented as noise, due to corruption by standing waves.
Also, what is really being done here is to speed up, or slow down, the wave front speed over the entire surface, to exactly that speed needed to emit a coherent wave front into the air, as the impulse traverses the driver surface. The white paper tests, shown on the last two pages, clearly indicate that more energy is getting off of the driver surface, before the final terminus of the tweeter in use.
Bud
Crank up the WD 40 machine... here we go.
The first thing done was to remove all of the internal foam damping material. Second was to "letter" this block pattern , on the inside, using a flat acrylic model paint, right out of the bottle . This paint was applied directly to the titanium surface, aluminum surface and the bottom edge of the paper using Speed Ball A series, 1 to 5, calligraphy pens (the ones with a bent tip). The pattern template is supplied by printing on a sheet of paper, with printing and scaling provided by Corel Draw 4 or later. Cut the round pattern out, apply it to a thin cardboard stiffener and you are ready to "letter". The scaled pattern needs to be a bit smaller than a direct size, so it settles deeper into the top of the cone than where you are going to apply the pattern. This pattern application location is the bottom edge of each material stage. The same process is applied to the outer surfaces, in the same places, though moved up a bit due to the glue overlap. In this case the ring printed by Corel needs to have the center cut out and it needs to be slightly larger than the applied pattern so that it will sink towards the bottom, underneath where the pattern is to be lettered.
The pattern does not need to be particularly precise so skill needs are rudimentary and if you can hold a calligraphy pen you can perform the needed activity. Best to learn on cheap paper speakers first. And, you will be amazed by how good these things really are.
Application of the conformal coating, on metal surfaces is only over the pattern, not the entire metal surfaces. For the paper you can apply it over all of the cone material, for much deeper bass as it will stiffen the paper, or just over the pattern for what has always been available.
Since this process adds mass only on the transverse wave boundary layer, the amount of mass needed is infinitesimal compared to what is needed to mass damp the entire driver surface. This is true regardless of materials or frequencies being controlled and works as well in infrasonic as it does in ultrasonic, though the pattern is comprised of really tiny blocks of printed material in the ultrasonic realm.
To experiment with dome tweeters and other small radiators you will need to acquire a range of technical lettering pens from the days of yore when mechanical drawings were done by hand on vellum paper. Since this is a scalar architecture, with the same number of blocks for any given ring diameter you will need some pretty fine points and to cut the acrylic paint with water by 10% or so.
Yes, I am the mad fool who developed this, so I can provide you with a Corel file should you be interested in experimentation.
The claims I can make are quite extensive but the one that I really like the benefits of the most are the resulting infinite resolution of micro dynamic signals and the addition of many dB of headroom before compression sets in. All of the information revealed by the process has always been there, just unintelligibly presented as noise, due to corruption by standing waves.
Also, what is really being done here is to speed up, or slow down, the wave front speed over the entire surface, to exactly that speed needed to emit a coherent wave front into the air, as the impulse traverses the driver surface. The white paper tests, shown on the last two pages, clearly indicate that more energy is getting off of the driver surface, before the final terminus of the tweeter in use.
Bud
Hi Bud
Thanks for the info - and I personally would replace the phrase "mad fool" with "mad scientist". I'm a bit familiar with standing wave theory in airfoil designs - but that is a different application. In electronics and waveguide theory there are some applications especially used in phased array radar systems the traveling wave tubes - again a different application. But air can be considered as a "fluid" when considering the physics involved with compression and resistance to flow. The added problem with air is that it can be compressed where most fluids cannot. I understand your theory on the break-up of the standing waves with your EnABLE pattern which you have patented and I have taken the time to look over your patent at the USGPO. I took particular interest in the application of the pattern around the baffle of the speaker and on the surface of a dome shaped speaker - which might be of use in this type of project. I also took note of the math calculations used in the patent and considered doing just what you said when you stated to draw it up Coral Draw (or something of that sort). I was considering printing it out on a thin sheet of vellum and adhere it to the speaker cone but I was unsure as to what type of material was being used to perform the actual mechanical breakup of the standing wave. I was considering using some speaker dope and powered felt as a place to start and was also considering material to use on the speaker baffle - perhaps some cut up sections of felt pad. But 1st things 1st - I think Covey said that - Build a reference speaker as a base from which to work and compare and mamboni's design seems to be a very good starting point. I should also point out that I haven't been fooling around with audio since the mid 70's when I used to repair them. I used to have a complete set of those nice pens when I designed PWB's the old fashioned way - with Bishops red & blue tape on a precision grid - then I touched up the photo dropouts with the pins.
Isn't something similar to your EnABLE pattern being used to breakup rip tide currents? I seem to remember something like that in Popular Science. BTW - have you ever looked into an application for use with SONAR - might be something there.
Thanks for the info - and I personally would replace the phrase "mad fool" with "mad scientist". I'm a bit familiar with standing wave theory in airfoil designs - but that is a different application. In electronics and waveguide theory there are some applications especially used in phased array radar systems the traveling wave tubes - again a different application. But air can be considered as a "fluid" when considering the physics involved with compression and resistance to flow. The added problem with air is that it can be compressed where most fluids cannot. I understand your theory on the break-up of the standing waves with your EnABLE pattern which you have patented and I have taken the time to look over your patent at the USGPO. I took particular interest in the application of the pattern around the baffle of the speaker and on the surface of a dome shaped speaker - which might be of use in this type of project. I also took note of the math calculations used in the patent and considered doing just what you said when you stated to draw it up Coral Draw (or something of that sort). I was considering printing it out on a thin sheet of vellum and adhere it to the speaker cone but I was unsure as to what type of material was being used to perform the actual mechanical breakup of the standing wave. I was considering using some speaker dope and powered felt as a place to start and was also considering material to use on the speaker baffle - perhaps some cut up sections of felt pad. But 1st things 1st - I think Covey said that - Build a reference speaker as a base from which to work and compare and mamboni's design seems to be a very good starting point. I should also point out that I haven't been fooling around with audio since the mid 70's when I used to repair them. I used to have a complete set of those nice pens when I designed PWB's the old fashioned way - with Bishops red & blue tape on a precision grid - then I touched up the photo dropouts with the pins.
Isn't something similar to your EnABLE pattern being used to breakup rip tide currents? I seem to remember something like that in Popular Science. BTW - have you ever looked into an application for use with SONAR - might be something there.
damping vs damping
I have not used any materials except the acrylic paint to create the blocks with. I suspect others will work as this does seem to be a local mass interruption, in an area that is inherently low mass and high energy per sq CM. The paint has always performed well on every surface I have tried, and since I have been fooling around with this since 1973, there are a lot of treated surfaces by now.
That it works on incident surfaces is also quite interesting. Relieves the normal diffraction at the edges of boxes and other deflection plates. Use in horns and drivers is quite noticeable with more energy density in the air, very few reflection artifacts in the horns and a general lack of horn "cry" due to the standing waves that populate most horn flares.
With the average speaker box treated and all drivers also treated the box disappears from the sound field and no artifacts give rise to it's reappearance, and the perceived sound field is immense. Done properly there are no "hot spots" at any frequency and images with multiple frequencies or a range of frequencies extending across more than one driver are pin point in their placement, with respect to our ear / correlator / conscious comprehension, and do not wander due to frequency changes, even across differing types of radiators.
This is of course some kind of "speaker holy grail" too good to be true and you can be sure that Not Invented Here has been the only response I have received from those very knowledgeable folks practicing their own form of this black art. To very good results by the way as the EnABL process has far less effect upon modern speakers than it did 30 years ago. Now it pretty much just accomplishes the original goal of eliminating transient standing waves, by making it impossible for them to form in the first place, without altering any of the other tonal and transient events in any way I have been able to measure. Certainly distortion plots and the included traces of various even and odd order HD are not visibly altered.
I was cautioned many year ago by a naval engineer not to mention Sonar in conjunction with this process as the government would and easily could co opt it, without paying me a penny and enforce my silence about the process and it's benefits.
Thanks for your thoughts, it is refreshing.
Bud
I have not used any materials except the acrylic paint to create the blocks with. I suspect others will work as this does seem to be a local mass interruption, in an area that is inherently low mass and high energy per sq CM. The paint has always performed well on every surface I have tried, and since I have been fooling around with this since 1973, there are a lot of treated surfaces by now.
That it works on incident surfaces is also quite interesting. Relieves the normal diffraction at the edges of boxes and other deflection plates. Use in horns and drivers is quite noticeable with more energy density in the air, very few reflection artifacts in the horns and a general lack of horn "cry" due to the standing waves that populate most horn flares.
With the average speaker box treated and all drivers also treated the box disappears from the sound field and no artifacts give rise to it's reappearance, and the perceived sound field is immense. Done properly there are no "hot spots" at any frequency and images with multiple frequencies or a range of frequencies extending across more than one driver are pin point in their placement, with respect to our ear / correlator / conscious comprehension, and do not wander due to frequency changes, even across differing types of radiators.
This is of course some kind of "speaker holy grail" too good to be true and you can be sure that Not Invented Here has been the only response I have received from those very knowledgeable folks practicing their own form of this black art. To very good results by the way as the EnABL process has far less effect upon modern speakers than it did 30 years ago. Now it pretty much just accomplishes the original goal of eliminating transient standing waves, by making it impossible for them to form in the first place, without altering any of the other tonal and transient events in any way I have been able to measure. Certainly distortion plots and the included traces of various even and odd order HD are not visibly altered.
I was cautioned many year ago by a naval engineer not to mention Sonar in conjunction with this process as the government would and easily could co opt it, without paying me a penny and enforce my silence about the process and it's benefits.
Thanks for your thoughts, it is refreshing.
Bud
Hello Bud:
You're EnABL approach to transverse wave termination is ingenious. Forgive my simplistic analysis, but your pattern of squares is behaving like a virtual diffraction grid, cause optimal phase cancellation in as much as the speed (and phase) of the wave are shifted as it traverses the stiffer lower impedance square-treated cone surface. Now, this in effect blurs the virtually cone-surround boundary, making the cone appear as an infinitely long transmission line. Your solution is elegant and simple. And I think I would be most interested in utilizing it in a future Walsh driver. I admit that I do not understand how the distribution of the squares is calculated for the woofer cone however.
I wanted to discuss the felt approach I implemented vis-a-vis a comment you made about it being mass loading. When I conceived the felt approach, the idea of adding progressive mass to the cone to achieve wave termination and simulate an infinite transmission line was the intuition. However, I discovered something unexpected - the felt fabric is incredibly light. In fact, after the felt treatment the Fs of the woofer is lowered no more than 1-2 hz. Yet the wave terminating ability of the felt is extraordinary. I believe there is something else at work here, far more important than mass: the felt consists of thousands of fibers. I believe the fibers are acting as a huge surface and providing for a much more efficient coupling of vibrating cone surface with air. Normally, the cone-air interface is a very inefficient due to the very different acoustic impedances of solid paper and air. The felt dramatically increases the effective surface area of the cone - many tines over. The best analogy I can think of is the small intestine, which to the naked eye is lined my a smooth pinky mucosal surface. But, under the microscope the surface is covered by billions of tiny hairs (villi), and ultrastructurally, each of these villi have thousands of microvilli. The result is that the effective absorption area of the small intestine is increased over 100-fold.
One might ask: if the felt is increasing the efficiency of acoustic radiation from the cone surface, why does the woofer not become louder per input watt? The answer is that all these thousands of fibers each cause random sound cancelling phase shifts and are behaving more as a low Q reactive impedance. In a way, the felt fibers are acting as thousands of tiny versions of your EnABL squares. Of course, the low Q results from the fibers coupling well with air and efficiently wicking acoustic energy away from the cone into the air.
Based on listening, the felt surface treatment seems exceptionally selective in damping out the resonant stored energy and perceived white noise that normally plagues the paper cone in its upper pass band. The felt has little effect on the woofer when operating in it's lower pistonic band. The result is an incredibly quiet soundstage and exceptional clarity of midrange separation. Of course, this must be heard first hand to be judged for oneself. Do you per chance live near Pennsylvania?
You're EnABL approach to transverse wave termination is ingenious. Forgive my simplistic analysis, but your pattern of squares is behaving like a virtual diffraction grid, cause optimal phase cancellation in as much as the speed (and phase) of the wave are shifted as it traverses the stiffer lower impedance square-treated cone surface. Now, this in effect blurs the virtually cone-surround boundary, making the cone appear as an infinitely long transmission line. Your solution is elegant and simple. And I think I would be most interested in utilizing it in a future Walsh driver. I admit that I do not understand how the distribution of the squares is calculated for the woofer cone however.
I wanted to discuss the felt approach I implemented vis-a-vis a comment you made about it being mass loading. When I conceived the felt approach, the idea of adding progressive mass to the cone to achieve wave termination and simulate an infinite transmission line was the intuition. However, I discovered something unexpected - the felt fabric is incredibly light. In fact, after the felt treatment the Fs of the woofer is lowered no more than 1-2 hz. Yet the wave terminating ability of the felt is extraordinary. I believe there is something else at work here, far more important than mass: the felt consists of thousands of fibers. I believe the fibers are acting as a huge surface and providing for a much more efficient coupling of vibrating cone surface with air. Normally, the cone-air interface is a very inefficient due to the very different acoustic impedances of solid paper and air. The felt dramatically increases the effective surface area of the cone - many tines over. The best analogy I can think of is the small intestine, which to the naked eye is lined my a smooth pinky mucosal surface. But, under the microscope the surface is covered by billions of tiny hairs (villi), and ultrastructurally, each of these villi have thousands of microvilli. The result is that the effective absorption area of the small intestine is increased over 100-fold.
One might ask: if the felt is increasing the efficiency of acoustic radiation from the cone surface, why does the woofer not become louder per input watt? The answer is that all these thousands of fibers each cause random sound cancelling phase shifts and are behaving more as a low Q reactive impedance. In a way, the felt fibers are acting as thousands of tiny versions of your EnABL squares. Of course, the low Q results from the fibers coupling well with air and efficiently wicking acoustic energy away from the cone into the air.
Based on listening, the felt surface treatment seems exceptionally selective in damping out the resonant stored energy and perceived white noise that normally plagues the paper cone in its upper pass band. The felt has little effect on the woofer when operating in it's lower pistonic band. The result is an incredibly quiet soundstage and exceptional clarity of midrange separation. Of course, this must be heard first hand to be judged for oneself. Do you per chance live near Pennsylvania?
Hi Bud
Reading your bio I see that we share magnetics in common - but thread isn't about those sort of things. Perhaps I will PM you about a couple of thoughts there. I was thinking about baffles and the use of some paint mixed with fine sand silk screened on with a finish similar to fine sand paper. Silkscreen might also be a method with which to apply your pattern onto a speaker or other surface. I can feel the old mental rust beginning to break free. Retirement - I love the freedom - but it's a bit of a drag to not have all of my technical toys around to play with.
Reading your bio I see that we share magnetics in common - but thread isn't about those sort of things. Perhaps I will PM you about a couple of thoughts there. I was thinking about baffles and the use of some paint mixed with fine sand silk screened on with a finish similar to fine sand paper. Silkscreen might also be a method with which to apply your pattern onto a speaker or other surface. I can feel the old mental rust beginning to break free. Retirement - I love the freedom - but it's a bit of a drag to not have all of my technical toys around to play with.
Mamboni / EnABL
I have no doubt that you are actually providing what my EnABL process simulates, an infinite boundary to a cone terminus, by actually providing an essentially infinite boundary layer.
Very clever, and the first specific instance of the use of this powerful lever, an effective control of the boundary layer, to enforce this effect I have seen other than the process I worked out so long ago.
Hooray!!!!!.
A number of folks around the commercial side of the speaker industry are becoming aware of the problem with boundary layers and that the boundary layer is the only place to control it. As an example Dynavox uses filled polypropylene cones in their large diameter voice coil woofers. Of course this solution just eliminates any sort of boundary layer active control without actually eliminating the transient ringing, just it's duration.
I suspect that a combination of our processes would either be a spectacular success or an equally spectacular failure. I think we should collaborate.
Your description of the silence of the sound field around instruments, with no loss of reverberant information nor micro dynamic detail is very familiar to me. I listen to it almost daily, as I work with speaker cables and interconnect cables that can be tuned for how much dynamic color they preserve and, with excess, add to the energy passing through them. Both of these tools aid greatly in the design and vetting of the audio transformers that I am currently in the middle of the third round of R&D activity on.
Should we ask for a separate thread to continue this discussion on? I suppose we will have to have some private communications also.
I live in the Seattle area and am elderly enough that I do not travel much, so we may never meet. But what fun!
Bud
I have no doubt that you are actually providing what my EnABL process simulates, an infinite boundary to a cone terminus, by actually providing an essentially infinite boundary layer.
Very clever, and the first specific instance of the use of this powerful lever, an effective control of the boundary layer, to enforce this effect I have seen other than the process I worked out so long ago.
Hooray!!!!!.
A number of folks around the commercial side of the speaker industry are becoming aware of the problem with boundary layers and that the boundary layer is the only place to control it. As an example Dynavox uses filled polypropylene cones in their large diameter voice coil woofers. Of course this solution just eliminates any sort of boundary layer active control without actually eliminating the transient ringing, just it's duration.
I suspect that a combination of our processes would either be a spectacular success or an equally spectacular failure. I think we should collaborate.
Your description of the silence of the sound field around instruments, with no loss of reverberant information nor micro dynamic detail is very familiar to me. I listen to it almost daily, as I work with speaker cables and interconnect cables that can be tuned for how much dynamic color they preserve and, with excess, add to the energy passing through them. Both of these tools aid greatly in the design and vetting of the audio transformers that I am currently in the middle of the third round of R&D activity on.
Should we ask for a separate thread to continue this discussion on? I suppose we will have to have some private communications also.
I live in the Seattle area and am elderly enough that I do not travel much, so we may never meet. But what fun!
Bud
Thomas and Mamboni,
Please do email me with thoughts we can share.
Thomas, I have literally cracked the code on E/I transformers. I can build a push pull output that does not exhibit hysteresis induced remanence, no zero crossing distortion nor loss of micro dynamic coherence. This has allowed me to explore coil construction formats and dielectric barriers with an eye to matching core material B field permitivity to coil E field / D field permitivity. First results are "voiced" guitar outputs. But now I have really hijacked the thread and apologize to all.
Bud
Please do email me with thoughts we can share.
Thomas, I have literally cracked the code on E/I transformers. I can build a push pull output that does not exhibit hysteresis induced remanence, no zero crossing distortion nor loss of micro dynamic coherence. This has allowed me to explore coil construction formats and dielectric barriers with an eye to matching core material B field permitivity to coil E field / D field permitivity. First results are "voiced" guitar outputs. But now I have really hijacked the thread and apologize to all.
Bud
Hi Bud & Mamboni
I'm thinking: 1) design pattern for 10" cone (for use in this project using mamboni's existing speaker development). Designs or patterns could be developed for other cones as required. 2) print pattern on thin paper using large format printer. You could use a regular printer but large cones would require printing on more than one sheet of paper - or being broken into segments if printed on a single sheet of paper. Those segments would need to be joined and aligned. (Well maybe not - if you only did a section of cone at a time.) 3) remove paper material where printed leaving a stencil pattern in the paper. (Where is my 10KW laser CNC when I really need it!)
4) apply a "tacky" type of spray adhesive to the back of the paper. 3M makes one that I have used to tack up plastic sheeting when spray painting my rooms during remodeling - available at hardware stores. If applied to the paper stencil - not the speaker cone - it should leave little if any residue. 5) apply stencil to speaker cone. 6) mask off areas not to be painted 7) air brush on chosen material (paint, speaker dope, etc.) 7) remove stencil. 8) hook that bad boy up and let it GO - GO - GO!! 
BTW - Bud - Got anything that will do 8 T's for 100ms at 5cps and not require cryo cooling?
I'm thinking: 1) design pattern for 10" cone (for use in this project using mamboni's existing speaker development). Designs or patterns could be developed for other cones as required. 2) print pattern on thin paper using large format printer. You could use a regular printer but large cones would require printing on more than one sheet of paper - or being broken into segments if printed on a single sheet of paper. Those segments would need to be joined and aligned. (Well maybe not - if you only did a section of cone at a time.) 3) remove paper material where printed leaving a stencil pattern in the paper. (Where is my 10KW laser CNC when I really need it!)
4) apply a "tacky" type of spray adhesive to the back of the paper. 3M makes one that I have used to tack up plastic sheeting when spray painting my rooms during remodeling - available at hardware stores. If applied to the paper stencil - not the speaker cone - it should leave little if any residue. 5) apply stencil to speaker cone. 6) mask off areas not to be painted 7) air brush on chosen material (paint, speaker dope, etc.) 7) remove stencil. 8) hook that bad boy up and let it GO - GO - GO!! BTW - Bud - Got anything that will do 8 T's for 100ms at 5cps and not require cryo cooling?
Thomas,
I do have an Auto Cad 14 lisp program already written, that will turn cone outer diameter, inner diameter and length between termini into a pattern set, that could be used for this purpose.
I was originally going to use this, laid out flat, to make a photo sensitive negative from, so that I could make a photo resist print on silk screen, use that to print on paper material, (Hemp?) cut them out and form them into cones. With a bit of edumacation the program works quite well.
I did forget to mention that applying the pattern at both terminus edges of a treated surface is very beneficial. I wonder what a pattern of Mambonis's neat felt, applied to the EnABL pattern would provide?
Bud
I do have an Auto Cad 14 lisp program already written, that will turn cone outer diameter, inner diameter and length between termini into a pattern set, that could be used for this purpose.
I was originally going to use this, laid out flat, to make a photo sensitive negative from, so that I could make a photo resist print on silk screen, use that to print on paper material, (Hemp?) cut them out and form them into cones. With a bit of edumacation the program works quite well.
I did forget to mention that applying the pattern at both terminus edges of a treated surface is very beneficial. I wonder what a pattern of Mambonis's neat felt, applied to the EnABL pattern would provide?
Bud
Hi Bud
Hemp paper or cardboard (thin) is great stuff - very though and friendly to the environment. I checked ebay and about the closest I could get was hemp rolling paper - and if we start using that stuff it'll take like 5 or 6 years to get things finished - if we remembered what we started doing in the 1st place. I think the combo of felt and hemp would be a natural - I was checking into Gore-Tex but it looks to be hard to get unless I want to destroy a $160.00 jacket from REI. But if you think that felt has some fibers in it then the fiber count in Gore-Tex will blow you away. But this approach gets us into the area of speaker cone replacement - which while doable can be tricky. Plus we would need to fabricate the cones. That could be done but would present problems to others that follow and want to duplicate this project. Might be tempted to do a prototype for personal use tho
Visited Seattle on my trips to Boeing - loved it - loved the seafood. Have some buds in VC/BC. So what's the latest odds on Mt. R blowing it's lid? My buddies would always throw things at me when I asked them that one
Hemp paper or cardboard (thin) is great stuff - very though and friendly to the environment. I checked ebay and about the closest I could get was hemp rolling paper - and if we start using that stuff it'll take like 5 or 6 years to get things finished - if we remembered what we started doing in the 1st place. I think the combo of felt and hemp would be a natural - I was checking into Gore-Tex but it looks to be hard to get unless I want to destroy a $160.00 jacket from REI. But if you think that felt has some fibers in it then the fiber count in Gore-Tex will blow you away. But this approach gets us into the area of speaker cone replacement - which while doable can be tricky. Plus we would need to fabricate the cones. That could be done but would present problems to others that follow and want to duplicate this project. Might be tempted to do a prototype for personal use tho
Visited Seattle on my trips to Boeing - loved it - loved the seafood. Have some buds in VC/BC. So what's the latest odds on Mt. R blowing it's lid? My buddies would always throw things at me when I asked them that one
Hey BudP:
These guys are up in your neck of the woods and do laser and dye cutting. http://www.mag-knight.com/diecutting/
I don't have your pattern so really can't talk to them about a bid - plus - it's your pattern and your patent so for me to discuss anything without your permission would be way out of line
But I'm thinking that if enough interest in your EnABLE pattern is generated it might be worth considering having a pattern cut on to a vellum mask that could be applied to the speaker cone and removed once the pattern is applied with chosen material - say adhesive and powered felt - or paint, ink, speaker dope - whatever. These guys might be able to cut the lam's for your xformers too.
Just a thought
BTW - your xformer ideas could be a big hit with the tube and power supply forums - ya might want to check 'em out.
These guys are up in your neck of the woods and do laser and dye cutting. http://www.mag-knight.com/diecutting/
I don't have your pattern so really can't talk to them about a bid - plus - it's your pattern and your patent so for me to discuss anything without your permission would be way out of line
But I'm thinking that if enough interest in your EnABLE pattern is generated it might be worth considering having a pattern cut on to a vellum mask that could be applied to the speaker cone and removed once the pattern is applied with chosen material - say adhesive and powered felt - or paint, ink, speaker dope - whatever. These guys might be able to cut the lam's for your xformers too.
Just a thought
BTW - your xformer ideas could be a big hit with the tube and power supply forums - ya might want to check 'em out.
Many subjects
Thomas,
Your idea of a "tacky" template is quite a good one. The silk screen sock notion was always just too complicated and rife with Murphy crevices to really interest me. You seem to have enough enthusiasm to carry this off so let's try out your idea.
We need to find out what file format Knight prefer their information in. I will assume a vector file and I can produce most of them. What we also need to pursue is a correct template for the cone dimensions you are working with. Simple measurements of the diameter of the two openings and the length between will suffice for a first attempt. Then some small modifications to the thickness entry in the lisp program should give us a pattern for both sides of the cone.
A pattern applied to the "listening" side of a driver will provide about 70% of the control that treating both sides does. The energy pulse that traverses a free air diaphragm is reciprocal in nature. What you do to one side does have consequences for the emissions from the other side. This is true for all cone materials I have worked with, even the dead plastic diaphragms.
If you will email me at the location noted in my bio and provide pretty tight dimensions on the cone you have in mind, we can proceed. If the tacky template idea works out, it will provide an avenue for DIY's to tackle other cone types and sizes.
I was never able to successfully devise a program for projecting pattern blocks onto a dome surface, though there are still only two pattern rings needed. The solid geometry calculations just overwhelmed my poor brain when I attempted to translate the needed description to Auto Cad lisp.
So, feel free to charge ahead, I will be happy to provide intellectual, practical and even some financial support for the project. This is, after all, a public domain intellectual property and the only key I hold, how to make it work in reality, can be had for allowing me to participate in any commercial venture that arises. I am not a particularly greedy person and the patent runs it's course in six years in any event.
Bud
Thomas,
Your idea of a "tacky" template is quite a good one. The silk screen sock notion was always just too complicated and rife with Murphy crevices to really interest me. You seem to have enough enthusiasm to carry this off so let's try out your idea.
We need to find out what file format Knight prefer their information in. I will assume a vector file and I can produce most of them. What we also need to pursue is a correct template for the cone dimensions you are working with. Simple measurements of the diameter of the two openings and the length between will suffice for a first attempt. Then some small modifications to the thickness entry in the lisp program should give us a pattern for both sides of the cone.
A pattern applied to the "listening" side of a driver will provide about 70% of the control that treating both sides does. The energy pulse that traverses a free air diaphragm is reciprocal in nature. What you do to one side does have consequences for the emissions from the other side. This is true for all cone materials I have worked with, even the dead plastic diaphragms.
If you will email me at the location noted in my bio and provide pretty tight dimensions on the cone you have in mind, we can proceed. If the tacky template idea works out, it will provide an avenue for DIY's to tackle other cone types and sizes.
I was never able to successfully devise a program for projecting pattern blocks onto a dome surface, though there are still only two pattern rings needed. The solid geometry calculations just overwhelmed my poor brain when I attempted to translate the needed description to Auto Cad lisp.
So, feel free to charge ahead, I will be happy to provide intellectual, practical and even some financial support for the project. This is, after all, a public domain intellectual property and the only key I hold, how to make it work in reality, can be had for allowing me to participate in any commercial venture that arises. I am not a particularly greedy person and the patent runs it's course in six years in any event.
Bud
Hi Bud,
Mamboni specks a PIONEER W25GR31-51F 10" BUTYL SURR WOOFER (http://www.partsexpress.com/pe/show...tnumber=290-088) back in post #33. This woofer is desirable for a number of reasons but chief among them is it will go to at least 6 KHz - where most 10" woofers stop around 2K. Also the cone is of butyl construction which is important for its "sound". Not to mention that it is not an expensive speaker - so even if I destroy a couple while I'm fooling around it's not going to break the bank. I think that we may well need to treat both sides of the cone surface because using this woofer to simulate a Walsh device we will be listening to the sound produced by the back wall on the speaker cone and working around the spider most likely will block access to some areas of the rear surface. What are your thoughts on alignment requirements between the patterns on the inside versus the outside? I would think that the patterns should overlay each other and that misalignment could make things worse. On the other hand if the patterns are offset it might serve to breakup the edge reflections even more - and that could be a good thing!
Speaking of Walsh (and for that matter DDR, who make a similar transducer) have you shared your design with them? You don't need to answer that - I'm not trying to pry - it's just a suggestion. I would think that they might show an interest in the technology. I can see the "new and improved" ads now - "Our new speakers use the EnABLE technology (patented) that allows for - blah, blah, blah - your listening pleasure". At this juncture I'm not concerned with dome tweeters because I will be using a Heil AMT on the high end. I'm not interested in going commercial (famous last words) been there - done that - got the t-shirt. (One part of my business brain is sketching out a production line in the garage - the retired part of my brain is saying NO - this is a HOBBY - HELLO .)
I'll send you a PM "test message" to establish contact and exchange some ideas - I don't want to hijack the thread.
Mamboni specks a PIONEER W25GR31-51F 10" BUTYL SURR WOOFER (http://www.partsexpress.com/pe/show...tnumber=290-088) back in post #33. This woofer is desirable for a number of reasons but chief among them is it will go to at least 6 KHz - where most 10" woofers stop around 2K. Also the cone is of butyl construction which is important for its "sound". Not to mention that it is not an expensive speaker - so even if I destroy a couple while I'm fooling around it's not going to break the bank. I think that we may well need to treat both sides of the cone surface because using this woofer to simulate a Walsh device we will be listening to the sound produced by the back wall on the speaker cone and working around the spider most likely will block access to some areas of the rear surface. What are your thoughts on alignment requirements between the patterns on the inside versus the outside? I would think that the patterns should overlay each other and that misalignment could make things worse. On the other hand if the patterns are offset it might serve to breakup the edge reflections even more - and that could be a good thing!
Speaking of Walsh (and for that matter DDR, who make a similar transducer) have you shared your design with them? You don't need to answer that - I'm not trying to pry - it's just a suggestion. I would think that they might show an interest in the technology. I can see the "new and improved" ads now - "Our new speakers use the EnABLE technology (patented) that allows for - blah, blah, blah - your listening pleasure". At this juncture I'm not concerned with dome tweeters because I will be using a Heil AMT on the high end. I'm not interested in going commercial (famous last words) been there - done that - got the t-shirt. (One part of my business brain is sketching out a production line in the garage
- the retired part of my brain is saying NO - this is a HOBBY - HELLO .) I'll send you a PM "test message" to establish contact and exchange some ideas - I don't want to hijack the thread.
Spiders everywhere
Thomas,
From the EnABL point of view you can ignore the spider, but the basket legs need to be dealt with. Usually just the conformal coating material will suffice. Once the wave front has terminated from the bending board as a coherent wave, it exhibits the same properties as "live" sound does, in that it will wrap around and cross over disturbances without tonal alterations becoming readily evident. I am reasonably certain that the wave front being emitted by a Mamboni treated cone will exhibit these same characteristics.
I suspect that a combination of EnABL and Mamboni treatments will work very well together. One "complaint" that I always had with a fully EnABL treated Walsh driver as you would find in a set of Walsh two speakers,or any other type of cone after treatment, was that I had to be extremely careful with the reflections from within the box as the driver becomes very transparent to those, since they are just as phase coherent as the emissions from the front side. I suspect that the felt triangles will help to suppress that back wave sensitivity.
Bud
Thomas,
From the EnABL point of view you can ignore the spider, but the basket legs need to be dealt with. Usually just the conformal coating material will suffice. Once the wave front has terminated from the bending board as a coherent wave, it exhibits the same properties as "live" sound does, in that it will wrap around and cross over disturbances without tonal alterations becoming readily evident. I am reasonably certain that the wave front being emitted by a Mamboni treated cone will exhibit these same characteristics.
I suspect that a combination of EnABL and Mamboni treatments will work very well together. One "complaint" that I always had with a fully EnABL treated Walsh driver as you would find in a set of Walsh two speakers,or any other type of cone after treatment, was that I had to be extremely careful with the reflections from within the box as the driver becomes very transparent to those, since they are just as phase coherent as the emissions from the front side. I suspect that the felt triangles will help to suppress that back wave sensitivity.
Bud
Yum 