Actually, an empirical approach as described would probably be best at determining driver performance. The math behind bending wave behavior in complex shapes (cones) is complex to say the least...intractable even? Although, with computer sims that might not be true today.
If you could establish a coincident frequency the frequency of maximum coherence could be interpolated (bending wave velocity is proportional to frequency). I would try to place the cone angle for the coherency max at the highest audible. Just my guess.
As the frequency goes down (longer wavelengths) the wave front coherency probably is less an issue.
If you could establish a coincident frequency the frequency of maximum coherence could be interpolated (bending wave velocity is proportional to frequency). I would try to place the cone angle for the coherency max at the highest audible. Just my guess.
As the frequency goes down (longer wavelengths) the wave front coherency probably is less an issue.
Busy, but....
...this is how I relax and wind down, y'all. *G* A sanctioned diversion, as my spouse approves of all this. Wonders never cease...
Thanks, Six for your support. And I can relate to 'a pile of drivers and electronics gathering dust', as mine did and a lot still do. My 'workbench' resembles that...if you could see the dust under all the various 'n sundry hardware, tools, and other items awaiting attention. I've read that a cluttered workspace is actually a Good Thing...if so, I'm covered in that dept. *L*
Regarding the 'big job' Cochleus referred to, yes, we're buried. But we're plowing in overdrive and ready or not, We Will Persevere. And it wouldn't be the first time we've taken some 'homework' and 'to do's' to the jobsite. No one notices if we do...since we 'do' something rather unusual, everyone thinks it's SOP for us. As Robin Williams once said, "You can fool most of the people most of the time, and jerk the rest off." As long as you're charming and cheerful about what you're doing and act 'normal', nobody knows any better. And we really seem to amaze folks despite ourselves, so we'll just keep calm and carry on...
Anyway....back to topic. *S*
Spider/surround issues....At this time, I'm altering the dynamics of an existing driver so much that it's previous qualities have been reduced to whether it can tolerate it's new 'state', if you will. The spider's movement has been 'throttled' significantly, and acts now to keep the cone centered and cope with the new stress of the voice coil exciting the cone into vibration rather than excursion. This exhibits itself in higher heat generated in the voice coil, since it can't move as freely as it was originally designed to do. This is why I've opted for the V.4's a driver meant for a 'live music'/PA application, with a Kapton former, venting, and a high temp tolerance. I wanted something Meant to be abused, as I suspect I will at some time or another. ("Let's see if this pile can handle a Serious Crank.")
The surrounds are a part of the experiment. The V.3's have the .060" EVA foam surrounds, which are less compliant than, say, the foam or paper ones you have. But even with that in mind, they do allow a certain amount of movement while EVA is known for it's 'shock absorption' value. I consciously put the surrounds under a degree of pressure from the cone to minimize movement. But move they still do...the V.3's generate bass. Not 'deep' bass, but certainly enough for kick drums and bass lines to come through. Ergo my use of a sub to 'fill in' the bottom, which is something I'll continue doing on purpose....
The V.4's are going to receive .060" Santophrene foam surrounds....which is a more common material used for speakers. It's somewhat stiffer and denser than the EVA, with which I hope to see a little less compliance and perhaps better absorption of the descending waveforms from the cone. I'll also refrain from putting the cones under physical pressure, making the completed vc/cone/surround combination more 'static'. I still can adjust this component to hear what occurs as part of the 'work in progress'. We'll (well, I will) see what happens with the frequency response when I jerk them around a little in this way.
The original Ohms (the F and A) had to have compliance since they were a 'single source' full-range radiator. I've opted to Not go that route...to keep it simple, as their cones were/are complex structures not easy to duplicate. Just ask Dale Harder @ HHR about this and his quest to bring them into the 21st century. It's a hell of a hat trick that he's accomplished very well, and I stand in awe of his determination and work.
I opted to mimic the German Physiks units but with a somewhat larger cone. I studied the Walsh patent and the structure of the F's cone, looking at where the cone transitioned from aluminum to paper. The thought being was that Lincoln had a good rationale for doing so, based on his calcs on freq. Ergo the size of the V.3 and V.4 cones. The smaller radiators I posted the pic on are sized to the transition from titanium to aluminum...ergo, that size of cone.
The 'neck' of the cones is a much smaller diameter than the F's in both units; the lowers are 1", the new 'uppers' are .75". I'd bet and have noticed that this allows extension into higher freqs for both. I will consider this a 'good thing'. *G* The F's and A's, to my ears 'then', didn't have the 'reach' that we know in this era of cone and dome tweets, the 'shimmer' that we may not hear directly but experience none the less...
The upper radiators are spoofs of the Infinity 'ice cream cone' drivers, sans the foam infill. Having owned a pair of them, I'd always felt they were damped too much by that infill. Having discussed that with someone who'd worked @ Infinity in that era and the compromises made to make them, I'm rolling the dice and placing my bet that they're better off without it. Those units were fragile; mine are worse. That's my compromise. *G* And so far, I'm pleased by what they're doing.... There is the option of an 'infill' that doesn't contact the interior of the cone, or a very lightweight surround...
The former I've done. The V.2's that are not only still functioning and have become my 'puters 'monitors' in my office have a foam cone inside the cone with no negative effect. I suspect they're damping internal wave generation and pressure waves, since they're a sealed space unlike the Ohms, both old and new. The use of the interior cone is from a study of the Hegeman patent, which predates the Ohm patent. Again, 'wetware' better than mine had a rationale....which works. A cone, unfilled, has a 'honking' quality not unlike a megaphone and definitely not terribly musical. Filled, they stop 'honking' and behave. Yet another good thing IMHO...
As for sealing the base...I'd wondered if treating the unit as an 'acoustic suspension' volume would have an effect on their performance. Well, it certainly seems that way. The interior volume, sealed, acts like a 'spring', limiting excursion. Which is desirable and lets the surround do it's absorption 'thang' without having to cope with compliance as much. Another G.T. *G*
The V.3's with an 'open' base are mounted on a sealed PVC column. The column has it's fundamental freq, which likely effects the unit's fundamental freq as a whole. The V.4's will have a sealed base...still on a column to raise it to a proper height, but will lack a column's 'input' into the 'system' as a whole. I'm playing a hunch...again, we'll wait to hear what occurs.
Backing up to the upper radiators for a sec....I'm considering trying a very light surround material, although attaching it to the edge of 2 mil aluminum will be real challenge. It flexes if you blow on it hard.... When I first made a pair of Walsh's (the V.1's), one had an EVA surround, the other made from dental dam latex. Very light, very flexible, much like the surface of an inflated balloon. And that unit sounded horrible at anything above a whisper, much too compliant. But, for a 'tweeter' variant....it just might work on damping the back waves for something that operating at those freq. A thing to try....later...*L*
Power....mmm....well, the V.3's with their current 'tweeters' can be played loud enough long enough to drive the receiver into shutdown. Part of this likely is due to the ohmage, which I calc is running betwixt 2~3 per unit x4 units running in tandem. The V.4 'woofers' are rated at 100 wrms, 400 peak. I'm going to bi-amp them with an digital xover to sidestep the ohms issue, and run separate amps to do so....
Walsh's as I'm making them individually are not as 'loud' as a conventional speaker as one experiences them. I'll chalk that up to they're being an omni....instead of having a radiator pointed at you, they're radiating 360, ergo less 'coming at you' directly. However, when 'massed' (more than a pair), they have an 'additive' effect, much like a line source. I've discussed with Cochleus 'elsewhere' the thought of 'stacking' radiators vertically. I'm doing that now, using the V.2's with the pair of radiators that I made for the V.3.5 experiment. Those radiators are the same size as the V.2's; they just have a less robust driver above them. They're stacked vertically in my office. I can drive myself out of the room with them....
A V.2 has the same radiating surface as a 7" speaker. Do the math for 4.
A V.3 is eq to a 10". The question becomes can I make a radiator that can withstand 100 watts in the V.4's....
If I start stacking them (the V.5's?), what will happen? Yes, room reflection is a factor....but, working on placement in a better space?
Can I get your socks to begin to unravel? *L* And make you smile while it's happening?
What if this array was 6' tall? A 'line source' Walsh?
These are the things that 'float my boat' while merely making a living doing my 'real job', as involving and ultimately interesting as it can be...
Cochleus is correct with his analysis and comments on the behaviour of a cone under excitation. My experience in discussing the issue with him, and his rigor at the 'why' what occurs, drives my opinions of the 'details' of what's happening where the cone meets the air about it. I'm more of a 'how' kinda person....'how' does one combine materials to make it all behave in the fashion desired....
I have an odd 'knack' at doing this sort of thing....*G* I 'guess good'. Mom must have dropped me 'just right' somehow...*L*
Anyhow, at the end of the day, this quest amuses me, keeps me out of trouble, keeps the gray matter churned, and allows me to listen to the music I like in a manner that's rare to experience....
It almost allows you to 'walk Through' or 'be onstage' with the performance.
THAT'S WHAT I'M TRYING TO DO. I have the capability to induce 'delay' on the back pair of speakers. Can I 'pull' the sound field I'm creating 'into' a space coherently? Can it be coherent enough that you can 'walk around' the vocalist, or the lead guitar?
An engineer with Teac a couple of decades ago was trying to do just that. Pre-computers, no algorithms, just multi-channel tapes and a speaker array that had to be in a custom space because you were literally surrounded by speakers....
Is real holographic sound possible?
I dunno....but it 'sounds' like something fun to play with....or within....
...this is how I relax and wind down, y'all. *G* A sanctioned diversion, as my spouse approves of all this. Wonders never cease...
Thanks, Six for your support. And I can relate to 'a pile of drivers and electronics gathering dust', as mine did and a lot still do. My 'workbench' resembles that...if you could see the dust under all the various 'n sundry hardware, tools, and other items awaiting attention. I've read that a cluttered workspace is actually a Good Thing...if so, I'm covered in that dept. *L*
Regarding the 'big job' Cochleus referred to, yes, we're buried. But we're plowing in overdrive and ready or not, We Will Persevere. And it wouldn't be the first time we've taken some 'homework' and 'to do's' to the jobsite. No one notices if we do...since we 'do' something rather unusual, everyone thinks it's SOP for us. As Robin Williams once said, "You can fool most of the people most of the time, and jerk the rest off." As long as you're charming and cheerful about what you're doing and act 'normal', nobody knows any better. And we really seem to amaze folks despite ourselves, so we'll just keep calm and carry on...
Anyway....back to topic. *S*
Spider/surround issues....At this time, I'm altering the dynamics of an existing driver so much that it's previous qualities have been reduced to whether it can tolerate it's new 'state', if you will. The spider's movement has been 'throttled' significantly, and acts now to keep the cone centered and cope with the new stress of the voice coil exciting the cone into vibration rather than excursion. This exhibits itself in higher heat generated in the voice coil, since it can't move as freely as it was originally designed to do. This is why I've opted for the V.4's a driver meant for a 'live music'/PA application, with a Kapton former, venting, and a high temp tolerance. I wanted something Meant to be abused, as I suspect I will at some time or another. ("Let's see if this pile can handle a Serious Crank.")
The surrounds are a part of the experiment. The V.3's have the .060" EVA foam surrounds, which are less compliant than, say, the foam or paper ones you have. But even with that in mind, they do allow a certain amount of movement while EVA is known for it's 'shock absorption' value. I consciously put the surrounds under a degree of pressure from the cone to minimize movement. But move they still do...the V.3's generate bass. Not 'deep' bass, but certainly enough for kick drums and bass lines to come through. Ergo my use of a sub to 'fill in' the bottom, which is something I'll continue doing on purpose....
The V.4's are going to receive .060" Santophrene foam surrounds....which is a more common material used for speakers. It's somewhat stiffer and denser than the EVA, with which I hope to see a little less compliance and perhaps better absorption of the descending waveforms from the cone. I'll also refrain from putting the cones under physical pressure, making the completed vc/cone/surround combination more 'static'. I still can adjust this component to hear what occurs as part of the 'work in progress'. We'll (well, I will) see what happens with the frequency response when I jerk them around a little in this way.
The original Ohms (the F and A) had to have compliance since they were a 'single source' full-range radiator. I've opted to Not go that route...to keep it simple, as their cones were/are complex structures not easy to duplicate. Just ask Dale Harder @ HHR about this and his quest to bring them into the 21st century.
It's a hell of a hat trick that he's accomplished very well, and I stand in awe of his determination and work.I opted to mimic the German Physiks units but with a somewhat larger cone. I studied the Walsh patent and the structure of the F's cone, looking at where the cone transitioned from aluminum to paper. The thought being was that Lincoln had a good rationale for doing so, based on his calcs on freq. Ergo the size of the V.3 and V.4 cones. The smaller radiators I posted the pic on are sized to the transition from titanium to aluminum...ergo, that size of cone.
The 'neck' of the cones is a much smaller diameter than the F's in both units; the lowers are 1", the new 'uppers' are .75". I'd bet and have noticed that this allows extension into higher freqs for both. I will consider this a 'good thing'. *G* The F's and A's, to my ears 'then', didn't have the 'reach' that we know in this era of cone and dome tweets, the 'shimmer' that we may not hear directly but experience none the less...
The upper radiators are spoofs of the Infinity 'ice cream cone' drivers, sans the foam infill. Having owned a pair of them, I'd always felt they were damped too much by that infill. Having discussed that with someone who'd worked @ Infinity in that era and the compromises made to make them, I'm rolling the dice and placing my bet that they're better off without it. Those units were fragile; mine are worse. That's my compromise. *G* And so far, I'm pleased by what they're doing.... There is the option of an 'infill' that doesn't contact the interior of the cone, or a very lightweight surround...
The former I've done. The V.2's that are not only still functioning and have become my 'puters 'monitors' in my office have a foam cone inside the cone with no negative effect. I suspect they're damping internal wave generation and pressure waves, since they're a sealed space unlike the Ohms, both old and new. The use of the interior cone is from a study of the Hegeman patent, which predates the Ohm patent. Again, 'wetware' better than mine had a rationale....which works. A cone, unfilled, has a 'honking' quality not unlike a megaphone and definitely not terribly musical. Filled, they stop 'honking' and behave. Yet another good thing IMHO...
As for sealing the base...I'd wondered if treating the unit as an 'acoustic suspension' volume would have an effect on their performance. Well, it certainly seems that way. The interior volume, sealed, acts like a 'spring', limiting excursion. Which is desirable and lets the surround do it's absorption 'thang' without having to cope with compliance as much. Another G.T. *G*
The V.3's with an 'open' base are mounted on a sealed PVC column. The column has it's fundamental freq, which likely effects the unit's fundamental freq as a whole. The V.4's will have a sealed base...still on a column to raise it to a proper height, but will lack a column's 'input' into the 'system' as a whole. I'm playing a hunch...again, we'll wait to hear what occurs.
Backing up to the upper radiators for a sec....I'm considering trying a very light surround material, although attaching it to the edge of 2 mil aluminum will be real challenge. It flexes if you blow on it hard.... When I first made a pair of Walsh's (the V.1's), one had an EVA surround, the other made from dental dam latex. Very light, very flexible, much like the surface of an inflated balloon. And that unit sounded horrible at anything above a whisper, much too compliant. But, for a 'tweeter' variant....it just might work on damping the back waves for something that operating at those freq. A thing to try....later...*L*
Power....mmm....well, the V.3's with their current 'tweeters' can be played loud enough long enough to drive the receiver into shutdown. Part of this likely is due to the ohmage, which I calc is running betwixt 2~3 per unit x4 units running in tandem. The V.4 'woofers' are rated at 100 wrms, 400 peak. I'm going to bi-amp them with an digital xover to sidestep the ohms issue, and run separate amps to do so....
Walsh's as I'm making them individually are not as 'loud' as a conventional speaker as one experiences them. I'll chalk that up to they're being an omni....instead of having a radiator pointed at you, they're radiating 360, ergo less 'coming at you' directly. However, when 'massed' (more than a pair), they have an 'additive' effect, much like a line source. I've discussed with Cochleus 'elsewhere' the thought of 'stacking' radiators vertically. I'm doing that now, using the V.2's with the pair of radiators that I made for the V.3.5 experiment. Those radiators are the same size as the V.2's; they just have a less robust driver above them. They're stacked vertically in my office. I can drive myself out of the room with them....
A V.2 has the same radiating surface as a 7" speaker. Do the math for 4.
A V.3 is eq to a 10". The question becomes can I make a radiator that can withstand 100 watts in the V.4's....
If I start stacking them (the V.5's?), what will happen? Yes, room reflection is a factor....but, working on placement in a better space?
Can I get your socks to begin to unravel? *L* And make you smile while it's happening?
What if this array was 6' tall? A 'line source' Walsh?
These are the things that 'float my boat' while merely making a living doing my 'real job', as involving and ultimately interesting as it can be...
Cochleus is correct with his analysis and comments on the behaviour of a cone under excitation. My experience in discussing the issue with him, and his rigor at the 'why' what occurs, drives my opinions of the 'details' of what's happening where the cone meets the air about it. I'm more of a 'how' kinda person....'how' does one combine materials to make it all behave in the fashion desired....
I have an odd 'knack' at doing this sort of thing....*G* I 'guess good'. Mom must have dropped me 'just right' somehow...*L*
Anyhow, at the end of the day, this quest amuses me, keeps me out of trouble, keeps the gray matter churned, and allows me to listen to the music I like in a manner that's rare to experience....
It almost allows you to 'walk Through' or 'be onstage' with the performance.
THAT'S WHAT I'M TRYING TO DO. I have the capability to induce 'delay' on the back pair of speakers. Can I 'pull' the sound field I'm creating 'into' a space coherently? Can it be coherent enough that you can 'walk around' the vocalist, or the lead guitar?
An engineer with Teac a couple of decades ago was trying to do just that. Pre-computers, no algorithms, just multi-channel tapes and a speaker array that had to be in a custom space because you were literally surrounded by speakers....
Is real holographic sound possible?
I dunno....but it 'sounds' like something fun to play with....or within....
Fascinating. Oddly it makes sense to me too. I am also a try/modify kind of guy - but at this time all I can do is give encouragement and ask questions. The multi-driver, multi-amp approach seems like the way to go, too complex and expensive for mass-market success (MBL/Physiks) but should provide outstanding results for someone with the skills and willingness to dial it in. Here are a few more questions based on the above...
Are you now replacing the driver's spiders as opposed to reusing the existing as the earlier PDFs showed? Or do you mean the spider is being further constrained by the new cone and surround compared to the original driver?
I wondered about the fill. How about a loose fiber like fiberglass? just enough to dampen the inside waves? I'm intrigued by the idea of a light (barely there) surround for the tweeter, just to keep the inside waves separate from the outside and avoid possible interference/cancellation between them....This is what I've noticed happens when I test a driver in open-air vs enclosed.
Fun indeed. I just got a refurbished Carver M5.0T with 251 wpc (at 8 ohms) and it was too loud past the 50% mark, but sounds MUCH better on my Ohm 2's than my wimpy Denon receiver at 70 wpc. I think Omni speakers like some headroom on the amp. Can you share how many watts you're feeding each driver?
Thanks for the detailed reply! this is one of the things I like most about a public forum - the evolution of a line of thought over time.
Six - Minneapolis
Are you now replacing the driver's spiders as opposed to reusing the existing as the earlier PDFs showed? Or do you mean the spider is being further constrained by the new cone and surround compared to the original driver?
I wondered about the fill. How about a loose fiber like fiberglass? just enough to dampen the inside waves? I'm intrigued by the idea of a light (barely there) surround for the tweeter, just to keep the inside waves separate from the outside and avoid possible interference/cancellation between them....This is what I've noticed happens when I test a driver in open-air vs enclosed.
...Power....mmm....well, the V.3's with their current 'tweeters' can be played loud enough long enough to drive the receiver into shutdown. Part of this likely is due to the ohmage, which I calc is running betwixt 2~3 per unit x4 units running in tandem. The V.4 'woofers' are rated at 100 wrms, 400 peak. I'm going to bi-amp them with an digital xover to sidestep the ohms issue, and run separate amps to do so....
...it 'sounds' like something fun to play with....or within....
Fun indeed. I just got a refurbished Carver M5.0T with 251 wpc (at 8 ohms) and it was too loud past the 50% mark, but sounds MUCH better on my Ohm 2's than my wimpy Denon receiver at 70 wpc. I think Omni speakers like some headroom on the amp. Can you share how many watts you're feeding each driver?
Thanks for the detailed reply! this is one of the things I like most about a public forum - the evolution of a line of thought over time.
Six - Minneapolis
Non-sequential sequesters...
Wow....Six survived my novella without his brain leaking out of his ears. *G*
But I'll be briefer, because the day is short and my list is long...
Well, the stand-alone xover/multi-amp approach is just for the short term and an available option for me. With the xover I'll be able to determine which type and what parameters will work, and develop a suitable passive later. So there's that...
Not replacing the existing spiders for now, and Yes, the spider is being constrained. I hope to vary the degree of constraint to get a handle on what'll work best/better. MHO is that the cone needs a high level of force to get excited without a great degree of excursion. The side effect is the voice coil warms up....which is what the original V.1's succumbed to, getting fused to the point of laminating themselves to their gaps. But that tragic event did inform and push the creation of the V.2's...
...which are traveling with us to FL, BTW. *L* I Am NOT going to cope with laptop speakers or a hotel clock radio or the speakers in the TV for 2+ months, NO. One must have some personal luxuries, and that's going to be mine.... Class D amp & patch cables as req'd., of course...
Infill could be fiberglass, rock wool, or any suitable damping material. I'm using the foam 'cause it was 'off the shelf', artificial flower forms from Michaels that just happened to be the right size at approx. the same angle as the cone wall. And I'm 'creatively lazy'...and it was and is just an idea I wanted to try for the 'what if'...
There is the interference/cancellation issue on the small drivers, but the open air vs. enclosed effect is more of an issue with lower freq, which is more noticeable. Higher freq have shorter wavelengths and don't turn corners very well, where bass freq do. I'm more interested in damping wave reflection from the edge of the cone to try to minimize 'bounce back' up the cone and the potential cancellations/interference....
Not a problem...Technics SA-DX950, 100wpc@6ohms. The Russound R1250MC that'll be the next drive source is a 12 channel amp, 35wpc@8, 50@4. I can bridge into 100@8 if desired, and all channels can be run independently. Not an 'audiophile mono-block jewel' to be sure, but I wanted flexibility over sheer 'pedigree specs'. Besides, a 1.5K$ amp for 250$ was a decent investment, and it weighs a ton. You can hook up 24 speakers to it if desired, has independent levels and delays, all the things a DIY speaker buff might want...
Well, at least, this one, anyway....*L*
Agreed, I like forums....this is one of 4 I haunt, but here is where I've gotten the most feedback and commentary, and a big thanks from yours truly for all that's been offered by all that have desired to do so. It's been a great help to have others weigh in on what I'm up to, and another POV from other fans of the Walsh drivers has helped steer this leaky boat towards a port.
As for my earlier 'whine', it's grown fruit. I've contacted a local builder of guitar amps whose interested in lending his ears for a critical listening session, as well as a builder of speakers he markets that's a not-too-far drive away. The latter is of particular interest in his opinion...he already markets an omni, and happens to be a buddy of the man that sparked my initial interest in this endeavour so long ago....
His friend wrote and posted this:
DECWARE - Radial Speaker Project
If Steve feels like tagging along, I'd be stunned, honored, and insanely pleased. And the more ears, the merrier I'll hope. And since this is an open post on a public website, he can consider this an invite.
...and it IS a small planet. *G*
Wow....Six survived my novella without his brain leaking out of his ears. *G*
But I'll be briefer, because the day is short and my list is long...
Well, the stand-alone xover/multi-amp approach is just for the short term and an available option for me. With the xover I'll be able to determine which type and what parameters will work, and develop a suitable passive later. So there's that...
Not replacing the existing spiders for now, and Yes, the spider is being constrained. I hope to vary the degree of constraint to get a handle on what'll work best/better. MHO is that the cone needs a high level of force to get excited without a great degree of excursion. The side effect is the voice coil warms up....which is what the original V.1's succumbed to, getting fused to the point of laminating themselves to their gaps. But that tragic event did inform and push the creation of the V.2's...
...which are traveling with us to FL, BTW. *L* I Am NOT going to cope with laptop speakers or a hotel clock radio or the speakers in the TV for 2+ months, NO. One must have some personal luxuries, and that's going to be mine....
Class D amp & patch cables as req'd., of course...Infill could be fiberglass, rock wool, or any suitable damping material. I'm using the foam 'cause it was 'off the shelf', artificial flower forms from Michaels that just happened to be the right size at approx. the same angle as the cone wall. And I'm 'creatively lazy'...and it was and is just an idea I wanted to try for the 'what if'...
There is the interference/cancellation issue on the small drivers, but the open air vs. enclosed effect is more of an issue with lower freq, which is more noticeable. Higher freq have shorter wavelengths and don't turn corners very well, where bass freq do. I'm more interested in damping wave reflection from the edge of the cone to try to minimize 'bounce back' up the cone and the potential cancellations/interference....
Not a problem...Technics SA-DX950, 100wpc@6ohms. The Russound R1250MC that'll be the next drive source is a 12 channel amp, 35wpc@8, 50@4. I can bridge into 100@8 if desired, and all channels can be run independently. Not an 'audiophile mono-block jewel' to be sure, but I wanted flexibility over sheer 'pedigree specs'. Besides, a 1.5K$ amp for 250$ was a decent investment, and it weighs a ton. You can hook up 24 speakers to it if desired, has independent levels and delays, all the things a DIY speaker buff might want...
Well, at least, this one, anyway....*L*
Agreed, I like forums....this is one of 4 I haunt, but here is where I've gotten the most feedback and commentary, and a big thanks from yours truly for all that's been offered by all that have desired to do so. It's been a great help to have others weigh in on what I'm up to, and another POV from other fans of the Walsh drivers has helped steer this leaky boat towards a port.
As for my earlier 'whine', it's grown fruit. I've contacted a local builder of guitar amps whose interested in lending his ears for a critical listening session, as well as a builder of speakers he markets that's a not-too-far drive away. The latter is of particular interest in his opinion...he already markets an omni, and happens to be a buddy of the man that sparked my initial interest in this endeavour so long ago....
His friend wrote and posted this:
DECWARE - Radial Speaker Project
If Steve feels like tagging along, I'd be stunned, honored, and insanely pleased. And the more ears, the merrier I'll hope.
And since this is an open post on a public website, he can consider this an invite....and it IS a small planet. *G*
It took me awhile to recover...had a time finding a funnel small enough to fit into my ears...
G (c)
Glad you've mended, friend C. *G* Although "Physician, heal thyself!" comes to mind, at least, mine. I mean, my Dr., and it had varied results. Always a chancy feat...one never knows what psychic reformulation is begat by wetware re-installs and boots....
Speaking in tongues, perhaps not yours. Levitations of the garments of comely strangers in public domains. Walking through walls...
Tried the last one myself. It works, but your clothes stay on the side you've left. Tends to surprise anyone on the opposite side. Results vary widely therefore. Engage with care...
Speaking in tongues, perhaps not yours. Levitations of the garments of comely strangers in public domains. Walking through walls...
Tried the last one myself. It works, but your clothes stay on the side you've left. Tends to surprise anyone on the opposite side. Results vary widely therefore. Engage with care...
Decware paper still has me going. Like the idea of two spiders for keeping the coil centered. Wonder about winding length, and keeping the coil within the gap... Was not aware that keeping the coil within the gap gives better fidelity. How does the winding length impact cone force? Curious about the upside down cone, how different Would that sound compared to what Jerry is doing? I am guessing it was done to reduce basket impact on overall sound, but why not cut away the basket and make a more rigid, less vibration-prone structure like an ohm F? Seems like driving the narrow end of a steep cone directly from the VC is a simpler and more direct way to transmit bending motion. Finally, I like the tapered cone also, seems like it would have better FR than a straight-sided cone, but how would one build that out of thin aluminum or titanium sheet? (Stamped mold is beyond most Diy tools)
Sorry, too many questions, very few answers.
Six- Minneapolis.
Sorry, too many questions, very few answers.
Six- Minneapolis.
Break time...
...between installing an through-wall AC and building a bridge. The AC works..I'm chilling myself with a well-deserved brew. *G* Gets freakin' hot 2' from the ceiling....
I'd like 2 spiders too for an unsurrounded cone termination, but they're rare and expensive beasts that I'm reluctant and too cheap to take a knife to.
Coil Must remain within and properly located laterally to work properly, which is why I retain the existing spider.
Winding length vs. cone force: I'll go to the end of the limb and guess that a longer winding would create more force, but I suspect that it would effect or require a deeper gap, which would force a thicker magnet structure, and on and on... I lack the engineering chops to comment in detail on that. I'm just hacking up what seems to be my best call, at this juncture...
I've 'flipped' the cones (actually, the whole assembly) 'upside down' (small end down". It radiates towards your ankles....not so good...*L*
Basket cases (other than me *G*):
I'd like to 'flip' the baskets 'upside down' (big diameter 'up', surrounding the magnet assembly), but that would be a major piece of work beyond my current 'hack tech'. If I was in the market to mass-produce, I'd order them made that way. But that would entail mass quantities, an order from a supplier, etc. Someday, perhaps, over the rainbow.... Either that or a flat plate vs. a basket, but, same final situation....
The tapered cone is at the heart of the way the cone works...the larger the diameter, the lower the freq generated. Check out the Walsh patent:
Patent US3424873 - Coherent-sound loudspeaker - Google Patente
It's gets 'deep', but one of the diagrams illustrates the above. I'm not a rocket scientist either, but I can follow bread crumbs with the best of them. *G*
And YES, making cones IS a bit tricky. Thinner aluminum is a relative piece of cake...the thicker the material, the more effort and 'routines' one goes through to make it bend to your will is involved. I've created forms, both positive and negative, to engage in this process. It also involves a certain amount of 'ventilation of parts of more colorful language' and patience, not to mention physical and mental prep. And time....you don't want to be disturbed or distracted.
I want to do some titanium cones at some point in the future. I've already bookmarked a source or two for the raw material, but the cost of exotic cone material while I'm 'improving my production routines' (such as they are) keeps that in the 'Later' category. I suspect a cone of that material shouldn't be difficult to produce....I'd likely use 2mil material which should be easier to cut and 'roll', and it's not as subject to deformation as aluminum since it's more 'stiff'...less likely to wrinkle and kink....
I'm also interested in a carbon fiber cone, but that'll be a whole different set of ways 'n means to produce. That, and the stuff is worse than fiberglas to mess with. You Don't want to inhale it, it involves messing with resins, it involves (done properly) vacuum bagging to get the shape correct to the form which requires mold release chemical(s).... A 'Much Later' project, but definitely attractive as a goal.
Stamping cones puts you into production for a crowd handing you currency. One will require deeper pockets and some sort of production facility beyond the hobbyist's workbench. A stack of fabricated basket/magnet/voice coil/spidered assemblies that are 'good to go' for assembly. Lots of 'stuff' awaiting 'manufacturing magic'....
File under 'Pipe Dream'. Fill pipe with whatever floats one's boat. Or whatever is available in Minneapolis... *L*
There's always too many questions, but hopefully some answers have been rendered. *G*
Off to throw some caulk @ the new AC...then start to build a bridge....and I'm not kidding about the latter...
*L*
...between installing an through-wall AC and building a bridge. The AC works..I'm chilling myself with a well-deserved brew. *G* Gets freakin' hot 2' from the ceiling....
I'd like 2 spiders too for an unsurrounded cone termination, but they're rare and expensive beasts that I'm reluctant and too cheap to take a knife to.
Coil Must remain within and properly located laterally to work properly, which is why I retain the existing spider.
Winding length vs. cone force: I'll go to the end of the limb and guess that a longer winding would create more force, but I suspect that it would effect or require a deeper gap, which would force a thicker magnet structure, and on and on... I lack the engineering chops to comment in detail on that. I'm just hacking up what seems to be my best call, at this juncture...
I've 'flipped' the cones (actually, the whole assembly) 'upside down' (small end down". It radiates towards your ankles....not so good...*L*
Basket cases (other than me *G*):
I'd like to 'flip' the baskets 'upside down' (big diameter 'up', surrounding the magnet assembly), but that would be a major piece of work beyond my current 'hack tech'. If I was in the market to mass-produce, I'd order them made that way. But that would entail mass quantities, an order from a supplier, etc. Someday, perhaps, over the rainbow....
Either that or a flat plate vs. a basket, but, same final situation....The tapered cone is at the heart of the way the cone works...the larger the diameter, the lower the freq generated. Check out the Walsh patent:
Patent US3424873 - Coherent-sound loudspeaker - Google Patente
It's gets 'deep', but one of the diagrams illustrates the above. I'm not a rocket scientist either, but I can follow bread crumbs with the best of them. *G*
And YES, making cones IS a bit tricky. Thinner aluminum is a relative piece of cake...the thicker the material, the more effort and 'routines' one goes through to make it bend to your will is involved. I've created forms, both positive and negative, to engage in this process. It also involves a certain amount of 'ventilation of parts of more colorful language' and patience, not to mention physical and mental prep. And time....you don't want to be disturbed or distracted.
I want to do some titanium cones at some point in the future. I've already bookmarked a source or two for the raw material, but the cost of exotic cone material while I'm 'improving my production routines' (such as they are) keeps that in the 'Later' category. I suspect a cone of that material shouldn't be difficult to produce....I'd likely use 2mil material which should be easier to cut and 'roll', and it's not as subject to deformation as aluminum since it's more 'stiff'...less likely to wrinkle and kink....
I'm also interested in a carbon fiber cone, but that'll be a whole different set of ways 'n means to produce. That, and the stuff is worse than fiberglas to mess with. You Don't want to inhale it, it involves messing with resins, it involves (done properly) vacuum bagging to get the shape correct to the form which requires mold release chemical(s).... A 'Much Later' project, but definitely attractive as a goal.
Stamping cones puts you into production for a crowd handing you currency. One will require deeper pockets and some sort of production facility beyond the hobbyist's workbench. A stack of fabricated basket/magnet/voice coil/spidered assemblies that are 'good to go' for assembly. Lots of 'stuff' awaiting 'manufacturing magic'....
File under 'Pipe Dream'. Fill pipe with whatever floats one's boat.
Or whatever is available in Minneapolis... *L*There's always too many questions, but hopefully some answers have been rendered. *G*
Off to throw some caulk @ the new AC...then start to build a bridge....and I'm not kidding about the latter...
*L*
That is referred as Bl. Which is the magnetic flux times the wire length. So, Bl (force factor) is proportional to wire length.
Having a curve-linear cone shape would seem ideal. Hard(er) to do but, worth it? Works in theory...
G
...and Big Thanks to my friends for filling in the blank spots in my brain and the knowledge that should have been there...
But that figgers, C. More wire, wider winding, more force, higher BL. Likely more weight, but the added 'oomph' (technical term*L*) could compensate. But it's likely the numbers would've been crunched over that...
Hi, Jay! Long time no read.... And I never dug into my Inf's tweets to see what mystery stuffing was within. That routine would make a lot more sense to apply, unless an 'all-foam' infill was really more of an aerogel. Then that might have made them the tweeter they could have been.... Inf. just came out with them a couple of decades too soon.... Timing IS everything....*G*
But that figgers, C. More wire, wider winding, more force, higher BL. Likely more weight, but the added 'oomph' (technical term*L*) could compensate. But it's likely the numbers would've been crunched over that...
Hi, Jay! Long time no read....
And I never dug into my Inf's tweets to see what mystery stuffing was within. That routine would make a lot more sense to apply, unless an 'all-foam' infill was really more of an aerogel. Then that might have made them the tweeter they could have been.... Inf. just came out with them a couple of decades too soon.... Timing IS everything....*G*
Oh, and BTW...
It's been 2 years for me here @ diyA, the bulk of it spent in this forum, chasing after this odd version of an obtuse vision. I want to thank all who've spent their time and mental energy sifting through my posts and lending a thought and a hand to my quest.
I wouldn't be where I am or where I'm heading without y'all. A tip of the hat, a fist-bump, a handshake, and a raised glass to all of you.
Thank You Very Much. *BS* You've made the path easier to negotiate, stumbling though I may despite the illumination. But I wander so....
...and approaching the century page, too....
It's been 2 years for me here @ diyA, the bulk of it spent in this forum, chasing after this odd version of an obtuse vision. I want to thank all who've spent their time and mental energy sifting through my posts and lending a thought and a hand to my quest.
I wouldn't be where I am or where I'm heading without y'all. A tip of the hat, a fist-bump, a handshake, and a raised glass to all of you.
Thank You Very Much. *BS* You've made the path easier to negotiate, stumbling though I may despite the illumination. But I wander so....
...and approaching the century page, too....
I've got more or less a similar problem, Jay. I work @ the real job, which of late has gone slightly ballistic. Not that I'll complain about that...after all, that's why we do what we do. The 'busy' that Coch referred to earlier will have us 8/1 in Tampa for 2+ months of install....and it's just Part 1 of 2. There's at least 3 jobs in betwixt, and about a half dozen irons of various btu levels pending After Part 2. And we've now 2 f/t employees helping us plow through it all, and they're excited and committed to making our little niche a bigger crack in the industry wall. Can't complain about that either....*G*
I listen to music gleaned from Spotify or streamcasters while 'puting the elements of our designs. The 'soundtrack of my life' isn't what some might consider the correct one for my age group (no dead Euros or consistent 'oldies/moldies'...all over the board, it might strike an observer as somewhat schizoid and vaguely demented but it amuses me). But, as one now 'legally old', I feel I'm now Obligated to present a stance that shows that you can basically do WTF you want and if others *tsk*tsk* at you, you can show them the door and admonish them to go back to sleep. *L*
I push my Walsh project along as the time and space present themselves. The side effect of being as busy as we is will allow me to gather the resources and the services that I want to 'improve the breed' without having to make the pennies scream from pinching, all with SAF....which was a very pleasant surprise to have support from that quarter.
We're still looking forward to building our own abode. We're starting to think that we're eventually going to have to move this road show to a larger space, as elbow room is becoming an issue. As much as we like being 'in town' as we are, it's getting cramped when we're involved in projects that are getting larger and of higher profile.
Lots to do...and ultimately, very satisfying at the end of the day. And growth certainly beats the alternative. *S*
Anyway, off topic as usual...*L*
I'm getting the notion that this forum has more lurkers that active posters. And that's fine...the 'door' is non-existent, as any forum should be, and will IMHO remain that way. Whenever you or that individual that's reading this scroll wants to contribute or just comment, the box is always blank and open to be filled. As I've essentially become the default moderator, 'till always remain thus.
...and I have made more friends here than I've the time to have to make IRL, other than the folks I come in contact with while conducting business. Y'all mean a lot to me. Y'all tolerate my 'humour', such as it is. Y'all tolerate my off-topic meanderings.
I couldn't ask for more. And I know that if it gets too out of hand, y'all have the option of entering a different URL, which is Fine and understood by this quarter.
But I appreciate those who stick around at whatever frequency that they deem to do so.
I'll likely be going 'mute' for awhile, soon. It's just part of the process at this end of the wire. But, like MacArthur or the Terminator, I'll be back. *L* And keeping an eye out in the meanwhile for whomever drops by...*S*...even if only to say Hi.
I listen to music gleaned from Spotify or streamcasters while 'puting the elements of our designs. The 'soundtrack of my life' isn't what some might consider the correct one for my age group (no dead Euros or consistent 'oldies/moldies'...all over the board, it might strike an observer as somewhat schizoid and vaguely demented but it amuses me). But, as one now 'legally old', I feel I'm now Obligated to present a stance that shows that you can basically do WTF you want and if others *tsk*tsk* at you, you can show them the door and admonish them to go back to sleep. *L*
I push my Walsh project along as the time and space present themselves. The side effect of being as busy as we is will allow me to gather the resources and the services that I want to 'improve the breed' without having to make the pennies scream from pinching, all with SAF....which was a very pleasant surprise to have support from that quarter.
We're still looking forward to building our own abode. We're starting to think that we're eventually going to have to move this road show to a larger space, as elbow room is becoming an issue. As much as we like being 'in town' as we are, it's getting cramped when we're involved in projects that are getting larger and of higher profile.
Lots to do...and ultimately, very satisfying at the end of the day. And growth certainly beats the alternative. *S*
Anyway, off topic as usual...*L*
I'm getting the notion that this forum has more lurkers that active posters. And that's fine...the 'door' is non-existent, as any forum should be, and will IMHO remain that way. Whenever you or that individual that's reading this scroll wants to contribute or just comment, the box is always blank and open to be filled. As I've essentially become the default moderator, 'till always remain thus.
...and I have made more friends here than I've the time to have to make IRL, other than the folks I come in contact with while conducting business. Y'all mean a lot to me. Y'all tolerate my 'humour', such as it is. Y'all tolerate my off-topic meanderings.
I couldn't ask for more. And I know that if it gets too out of hand, y'all have the option of entering a different URL, which is Fine and understood by this quarter.
But I appreciate those who stick around at whatever frequency that they deem to do so.
I'll likely be going 'mute' for awhile, soon. It's just part of the process at this end of the wire. But, like MacArthur or the Terminator, I'll be back. *L* And keeping an eye out in the meanwhile for whomever drops by...*S*...even if only to say Hi.
...and here's something that's worth a sharing moment....
Neuroscientists Still Don?t Know Why Music Sounds Good | WIRED
Noting that the scientific community refrains from studying the making of and the reproduction of music, which is perhaps the most intelligent approach of all.
Neuroscientists Still Don?t Know Why Music Sounds Good | WIRED
Noting that the scientific community refrains from studying the making of and the reproduction of music, which is perhaps the most intelligent approach of all.
I always enjoy reading your progress. I'm perhaps a bit older than you are, and work a more sedentary job, but I have "outside" jobs, too. I'm taking this week off to build my wife a new website (and do spring cleaning on the house). My speaker budget got used, though. We were rear-ended on the way to Church Easter Sunday, and the insurance company deemed the car totaled. We barely felt the collision, but that's what you get when you're driving a 12-year old car.
*Sigh*. "I want a hybrid". So we have a new car. And payments. No new speakers for a while.
*Sigh*. "I want a hybrid". So we have a new car. And payments. No new speakers for a while.