mag-lev-turntable
So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy |
mag-lev-turntable
On Thursday, November 10, 2016 at 2:16:10 PM UTC-5, micky wrote:
So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy Probably For Real. Too much/many "other" sources and information out there. Interesting idea. One does wonder how the centering and leveling functions work. I can figure out how they handle rotation. A half-price for pre-purchase is not a half-bad deal given it comes with an arm and cartridge. Peter Wieck Melrose Park, PA |
mag-lev-turntable
micky wrote:
So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy Oh, boy! Did you see how HIGH they levitate the platter? Geez, I have strong doubts it can be stable at that height. Also, the thing must have an insanely strong external magnetic field. Now, the only way I know one-sided levitation at low speeds can work is with something that TOTALLY excludes flux lines, ie. a superconductor. So, the only way this thing could work is with a spinning Halbach array under the platter (which would play HELL with a magnetic phono cartridge) or massive high-field magnets underneath and a room temperature superconductor in the platter. Hmmm, can't buy that yet... I know of no way to repel something ordinary with a steady magnetic field, although with strong tapered AC fields, it is possible to repel a conductor. I've seen this done with a big 3-phase AC motor stator and an aluminum platter. But, the motor draws insane current and the platter gets hot fast. Brooklyn? As in Brooklyn bridge? Yup, sounds pretty appropriate, I'm very skeptical of this one. I think it probably CAN be done, but not as a practical device, capable of operating right next to a megnetic phono cartridge. Jon |
mag-lev-turntable
In article , NONONOmisc07
@bigfoot.com says... So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy Lovely ide, but I'd want to know more... Presumably the huge floating height in the "photo" is merely to make it obvious, rather than being enough to de-couple a major earthquake? And how is the speed controlled? Mike |
mag-lev-turntable
In article ,
micky wrote: So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ The best you can do with vinyl is pretty poor; why bother? Plus, rumble has not been a problem on "ordinary" turntables (well, decent-quality ones) for quite a while. Isaac |
mag-lev-turntable
In article , Dave Platt
wrote: The other trick which puzzles me, is how they keep the magnetic levitation/centering/rotation field from being picked up by the cartridge, or keeping the magnitude of the pick-up down below the noise floor of the phono preamplifier. Perhaps they use a ceramic cartridge. The sound would suffer, but it would still look pretty cool. -- Jim |
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On Thursday, November 10, 2016 at 3:29:19 PM UTC-5, Jon Elson wrote:
Oh, boy! Did you see how HIGH they levitate the platter? Geez, I have strong doubts it can be stable at that height. Also, the thing must have an insanely strong external magnetic field. Now, the only way I know one-sided levitation at low speeds can work is with something that TOTALLY excludes flux lines, ie. a superconductor. https://en.wikipedia.org/wiki/Neodymium_magnet I have experienced these magnets directly - when we were in China, the novelty shops sold a device with what amounted to a metal puck, about the size of a hockey puck but half the thickness that could be suspended above a platform if "heads" or was very nearly impossible to remove from the platform except by sliding if "tails". Variations included a shaft that could be spun in suspension over a bed attached to the platform and another that could be twirled. When we tried to bring it back to the US in our checked baggage, we were called to the front of the plane and informed that these things were powerful enough to interfere with aircraft navigation systems - and that we would have to either get off the aircraft and mail it, or give it up. We gave it up. In any case, I would have no difficulty at all believing Neodymium magnets within the platter with a rotating field developed in the plinth reaching that distance. And, it would have the additional effect of 'centering' the platter as well. The platter *will* be quite heavy. Now, one more beneficial effect of this system: The field will be, effectively, two nested donuts, and they could be rather small relative to the 12" platter given the power of the static field (in the platter) - perhaps as little/small as 6". At that size, the platter would be a shield for the cartridge both magnetically and in rF. Note that the cartridge is always *ABOVE* the field with the platter between it and that field. Not that I am going to line up to purchase that TT. I am hooked on linear tracking arms - and unless/until that happens, it is only a neat trick, no more. Peter Wieck Melrose Park, PA |
mag-lev-turntable
On Fri, 11 Nov 2016 12:28:55 -0000, MJC
wrote: In article , says... ... There is another one out there, a vertical turntable. There are people putting money into that as well and it is not a really good idea. It is one hell of a novelty, as this is and if you got the money honey, go for it. Impress your friends and enemies as well. I'm sure a vertical turntable was marketed decades ago. I don't remember the supposed advantage, though... Mike. One advantage was that they could be built into boomboxes and an arm could be mounted on the front and the back. (No need to flip the record) I remember when they first Sharp samples showed up at Best Buy. They were monstrosities that I thought wouldn't sell and I was right. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
mag-lev-turntable
In article ,
micky wrote: So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy let's see, how many things can go wrong here. 1) the stylus has weight required for proper tracking. It will want to tilt the platter, and the torque will vary from edge to center. 2) there's friction at the stylus, making the platter want to rotate around the point of contact. 3) the base is still coupled to the platter through the magnetic field. Vibrations will still be coupled to the platter. 4) better have a UPS. You don't want that platter crashing down when the power goes out. 5) that large of a magnetic field wont interfere with the cartridge? 6) a rotating magnetic field driving the platter will introduce just as much wow and flutter as is introduced by the motor of a direct drive turntable. 7) an open window or a fan could easily blow that platter around creating even more distortion. And that's without putting much thought into it. But it seems they've already exceeded their goal and have more than $400,000. |
mag-lev-turntable
On Friday, November 11, 2016 at 10:15:18 AM UTC-5, Mark Storkamp wrote:
let's see, how many things can go wrong here. https://www.dropbox.com/s/huq5ehstso...tion.docx?dl=0 This is my wildly speculative speculation on how this system could work and be effective. Some points: a) Neodymium magnets are wildly powerful. And can be shaped more efficiently than many other materials. b) By offsetting the suspension rings as shown, the forces centering and keeping the platter level would be very strong - certainly stronger than most suspension springs for that matter. c) And there would be negligible elastic forces - that is, no wobble or bounce. That window fan would not have a chance. Damping, similarly. d) The wow and flutter issue, though very real, would be pretty much eliminated by the mass of the platter (considerable) coupled with the very negligible mass of the drive motor. e) As the platter is essentially frictionless, it would not take much to keep it running once started. I would anticipate a few seconds of start-up, but after that, gyroscopic effects would contribute to leveling and to speed control. The couple of grams on the stylus, again, would not have a chance.. f) The soft shut-down is already addressed. There is an on-board soft shut-down capacity that will raise the posts and lift the stylus. g) As to magnetic fields - consider that both the suspension field and the drive fields are static relative to each other. Meaning that there will be very little generated by way of stray fields, and that the platter, if properly designed, will be enough to shield the cartridge. Considering what goes on inside my HK/Rabco without ill effect, or my Revox B295, this would be low on my worry-scale. Again, this is a neat trick, not something I intend to purchase. But a neat trick that appears to be both possible and reasonable to execute. Peter Wieck Melrose Park, PA |
mag-lev-turntable
In article ,
" wrote: On Friday, November 11, 2016 at 10:15:18 AM UTC-5, Mark Storkamp wrote: let's see, how many things can go wrong here. https://www.dropbox.com/s/huq5ehstso...ation.docx?dl= 0 This is my wildly speculative speculation on how this system could work and be effective. Some points: a) Neodymium magnets are wildly powerful. And can be shaped more efficiently than many other materials. b) By offsetting the suspension rings as shown, the forces centering and keeping the platter level would be very strong - certainly stronger than most suspension springs for that matter. c) And there would be negligible elastic forces - that is, no wobble or bounce. That window fan would not have a chance. Damping, similarly. d) The wow and flutter issue, though very real, would be pretty much eliminated by the mass of the platter (considerable) coupled with the very negligible mass of the drive motor. e) As the platter is essentially frictionless, it would not take much to keep it running once started. I would anticipate a few seconds of start-up, but after that, gyroscopic effects would contribute to leveling and to speed control. The couple of grams on the stylus, again, would not have a chance. f) The soft shut-down is already addressed. There is an on-board soft shut-down capacity that will raise the posts and lift the stylus. g) As to magnetic fields - consider that both the suspension field and the drive fields are static relative to each other. Meaning that there will be very little generated by way of stray fields, and that the platter, if properly designed, will be enough to shield the cartridge. Considering what goes on inside my HK/Rabco without ill effect, or my Revox B295, this would be low on my worry-scale. Again, this is a neat trick, not something I intend to purchase. But a neat trick that appears to be both possible and reasonable to execute. Peter Wieck Melrose Park, PA Still seems like it would be a lot easier to use direct drive and air bearings. But since it's already been done, there wouldn't be as much money in it. |
mag-lev-turntable
On Thursday, November 10, 2016 at 2:16:10 PM UTC-5, micky wrote:
So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy Seems like a solution in search of a problem. In a world filled with people who now listen to MP3s or other forms of compression I wonder how many folks in the world would want this even if it does all it promises. And, I'm willing to bet that in a double blind test with even quality tables at the lower end of the spectrum, this toy's superiority would not be discernible, even if "audiophiles" do avoid double blind tests. |
mag-lev-turntable
On Friday, November 11, 2016 at 5:58:43 PM UTC-5, wrote:
On Thursday, November 10, 2016 at 2:16:10 PM UTC-5, micky wrote: So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy Seems like a solution in search of a problem. In a world filled with people who now listen to MP3s or other forms of compression I wonder how many folks in the world would want this even if it does all it promises. And, I'm willing to bet that in a double blind test with even quality tables at the lower end of the spectrum, this toy's superiority would not be discernible, even if "audiophiles" do avoid double blind tests. Just watched this video: https://www.youtube.com/watch?v=Ky0D00iyHAA There is a LOT of platter movement beyond the rotating moments going on here. Check 0:42 |
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On Thursday, November 10, 2016 at 12:29:19 PM UTC-8, Jon Elson wrote:
micky wrote: So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Oh, boy! Did you see how HIGH they levitate the platter? Geez, I have strong doubts it can be stable at that height. Also, the thing must have an insanely strong external magnetic field. Rogers Ritter published on a low-rumble magnetic suspension audio turntable back in the seventies; he was using magnetic attraction, and some active feedback, and was more interested in physics (gravity research) than audio. If these folk have a patent, that's not what they're doing. What puzzles me, is how there's enough reliable torque on the rotor. Now, the only way I know one-sided levitation at low speeds can work is with something that TOTALLY excludes flux lines, ie. a superconductor. To levitate a light platter at low speeds, you could get use fixed magnets and a 2-d conductor (pyrolitic graphite, doped, is light and has conductivity better than copper). Levitation distances of a few millimeters would work, after spin-up. No torque, though, if that's the only trick used. So, the only way this thing could work is with a spinning Halbach array .. or massive high-field magnets underneath and a room temperature superconductor Third possibility fixed magnets, spinning conductor. And smaller gap than the pic shows. Lots of info on the magnet-bearing subject: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19920018478.pdf |
mag-lev-turntable
On Thu, 10 Nov 2016 14:16:07 -0500, micky
wrote: So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy I wonder how it will work on my old warped vinyl records? Keeping it centered to within half a track width or less might be difficult with the needle applying a side force which is probably not consistent across the tone arm swing. I expect to see a levitated tone arm in the next version. Fighting gravity seems to be the current obsession in turntables: https://www.gramovox.com/pages/floating-record -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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mag-lev-turntable
Jon Elson wrote:
http://www.avsforum.com/mag-lev-turntable/ Oh, boy! Did you see how HIGH they levitate the platter? Geez, I have strong doubts it can be stable at that height. Also, the thing must have an insanely strong external magnetic field. Now, the only way I know one-sided levitation at low speeds can work is with something that TOTALLY excludes flux lines, ie. a superconductor. So, the only way this thing could work is with a spinning Halbach array under the platter (which would play HELL with a magnetic phono cartridge) or massive high-field magnets underneath and a room temperature superconductor in the platter. Hmmm, can't buy that yet... I know of no way to repel something ordinary with a steady magnetic field, although with strong tapered AC fields, it is possible to repel a conductor. I've seen this done with a big 3-phase AC motor stator and an aluminum platter. But, the motor draws insane current and the platter gets hot fast. ** OK, my two cents worth: The specs say the power consumption is only 12 watts - so static lift must be achieved with permanent magnets. There are no claims made for W&F so it must be poor, mostly due to imperfect centring of the LP. There are no claims that it is a genuine, hi-fi turntable. The platter wobbles and bounces for ages when disturbed, hence the use of support pegs when not running. The lack of important details and the OTT marketing videos makes it all smell very badly of SCAM. ..... Phil |
mag-lev-turntable
In sci.electronics.repair, on Thu, 10 Nov 2016 14:32:14 -0600, Jon Elson
wrote: micky wrote: So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy Oh, boy! Did you see how HIGH they levitate the platter? Geez, I have Good point. Even if they can raise it that high, it seems it would both conserve assets and increase reliability to just lift it a quarter inch. Wouldn't that give all the alleged advantages and no added disadvantages? So that makes it look like a fraud. Parts of the video looked to me someone like it was an animation. strong doubts it can be stable at that height. Also, the thing must have an insanely strong external magnetic field. ..... Brooklyn? As in Brooklyn bridge? Yup, sounds pretty appropriate, I'm very I only gave my cities because I sent copies of the first post to some friends, but I keep using different email addresses in different places and one said he couldn't tell if it was from me or someone he didn't know. skeptical of this one. I think it probably CAN be done, but not as a practical device, capable of operating right next to a megnetic phono cartridge. Jon |
mag-lev-turntable
In article ,
MJC wrote: In article , says... ... There is another one out there, a vertical turntable. There are people putting money into that as well and it is not a really good idea. It is one hell of a novelty, as this is and if you got the money honey, go for it. Impress your friends and enemies as well. I'm sure a vertical turntable was marketed decades ago. I don't remember the supposed advantage, though... Fit better in tiny Japanese apartments. Isaac |
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micky wrote:
Parts of the video looked to me someone like it was an animation. ** I had the same feeling, close-ups of the patter and PU looked like CGI. The Mag-Lev company is based in Slovenia - so likely immune from consumer fraud litigation and operating only over the net is such a warning. If it is somehow for real, the dudes have gone to considerable trouble to make it look FAKE. ..... Phil |
mag-lev-turntable
In sci.electronics.repair, on Fri, 11 Nov 2016 09:15:15 -0600, Mark
Storkamp wrote: And that's without putting much thought into it. But it seems they've already exceeded their goal and have more than $400,000. Oh yeah. So it should be on the market soon. :-) |
mag-lev-turntable
In sci.electronics.repair, on Fri, 11 Nov 2016 09:15:15 -0600, Mark
Storkamp wrote: 4) better have a UPS. You don't want that platter crashing down when the power goes out. From the kickstarter page: Accidents happen, and we know that sometimes you may encounter a power outage, so we’ve designed the turntable with a UPS system. This solution stores enough power to safely lift the tonearm, stop the record, and return the platter feet to resting position. This way the turntable and your record remain in perfect condition even when the unexpected happens. |
mag-lev-turntable
In sci.electronics.repair, on Fri, 11 Nov 2016 17:42:24 -0800, Jeff
Liebermann wrote: On Thu, 10 Nov 2016 14:16:07 -0500, micky wrote: So is this for real, or a kickstarter designed to cheat me out of my hard-earned money? http://www.avsforum.com/mag-lev-turntable/ Brooklyn-Baltimore Guy I wonder how it will work on my old warped vinyl records? I've got a 45 I must have left in the sun, and it has waves literally an inch and a half high, circling around the center. The needle can't come within an inch of the troughs. I call it a rock and roll record. Keeping it centered to within half a track width or less might be difficult with the needle applying a side force which is probably not consistent across the tone arm swing. I expect to see a levitated tone arm in the next version. And maybe a levitated easy chair and ottoman! Fighting gravity seems to be the current obsession in turntables: https://www.gramovox.com/pages/floating-record |
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MJC wrote:
I'm sure a vertical turntable was marketed decades ago. I don't remember the supposed advantage, though... I still own and use one, a Mitsubishi LT-5V. The main advantage to it, it's practically immune to rumble via outside sources. Within reason, stick it on a wobbly table with a loose floor, jump up and down while it's playing and, nothing. It's not the greatest turntable ever built for other things (besides looks) but it is good at that one thing. Up and down vibrations just don't bother it. -bruce |
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This entire discussion is fascinating!
I think that the concept is accepted in general. There is nothing particularly difficult with suspending one object over another using magnets. This has been done for years. Today, there are extremely powerful and stable magnets that make the process more easily achieved. There is nothing particularly difficult with shielding the cartridge from the magnets. As Phil noted, with a 12W power consumption, and stable PM fields, there is not a lot of stray magnetic fields happening here. So, what we are left with is the R&D & ergonomics required to go from prototype to production. As to scam, very possibly. But not certainly. Keeping in mind that the production of turntables these days outside of USB-based junkers is pretty much a cottage industry from small companies or tiny divisions of larger ones producing legacy devices. So, that a half-dozen Serbians might come up with a wild idea is actually somewhat touching. It is not as if Harmon-Kardon is going to buy out Jacob Rabinow, or Revox is going to turn a dozen Swiss machinist loose on the problem. This is where it will be happening. Again, I am hooked on linear TTs. Were this device to offer that option, I would be tempted. In another forum, a gentleman is discussing upgrading his TT and throwing around 5-figure numbers (US$). So, clearly, this TT is in the sparrow-feed range for that sort of individual. And, look at the cost of a Souther arm these days. Will it work? Too early to tell. It depends on the skills of those executing the concept. Can it work? Clearly, yes. Hand this to the Swiss, or a couple of really good machinists and give them unlimited resources, it would be done in a month. Would US$700,000 do it? Certainly not in Switzerland. At the Machine shop I worked in 40 years ago - absolutely. It is still extant by the way, and still very successful. Far from the dingy little building I worked in back then, today it looks like a clean room, only about two acres under roof. By amateurs in Serbia? Who knows. Peter Wieck Melrose Park, PA |
mag-lev-turntable
On 10/11/16 23:24, wrote:
snip There is another one out there, a vertical turntable. There are people putting money into that as well and it is not a really good idea. It is one hell of a novelty, as this is and if you got the money honey, go for it. Impress your friends and enemies as well. You possibly mean this one. The Gramovox Vertical Turntable - REVIEW https://www.youtube.com/watch?v=kvcoci3QLEk It's mad. -- Adrian C |
mag-lev-turntable
In sci.electronics.repair, on Sat, 12 Nov 2016 13:05:48 +0000 (UTC),
Bruce Esquibel wrote: MJC wrote: I'm sure a vertical turntable was marketed decades ago. I don't remember the supposed advantage, though... I still own and use one, a Mitsubishi LT-5V. I see one sold on ebay last year for 450. The main advantage to it, it's practically immune to rumble via outside sources. Within reason, stick it on a wobbly table with a loose floor, jump up and down while it's playing and, nothing. It's not the greatest turntable ever built for other things (besides looks) but it is good at that one thing. Up and down vibrations just don't bother it. -bruce |
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In sci.electronics.repair, on Fri, 11 Nov 2016 23:34:16 -0800 (PST),
Phil Allison wrote: micky wrote: Parts of the video looked to me someone [somewhat] like it was an animation. ** I had the same feeling, close-ups of the patter and PU looked like CGI. The Mag-Lev company is based in Slovenia - so likely immune from consumer fraud litigation and operating only over the net is such a warning. No wonder they *all* had Slovenic (?) names. If it is somehow for real, the dudes have gone to considerable trouble to make it look FAKE. Good point. Okay, that's 50,000 dollars I can use for something else. .... Phil |
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micky wrote:
** I had the same feeling, close-ups of the patter and PU looked like CGI. The Mag-Lev company is based in Slovenia - so likely immune from consumer fraud litigation and operating only over the net is such a warning. If it is somehow for real, the dudes have gone to considerable trouble to make it look FAKE. Good point. Okay, that's 50,000 dollars I can use for something else. ** You can find vids on the net from independent people - showing a Mag-Lev TT working. It really does float 50mm above the base and it really does spin at a pretty steady pace. There is some serious cleverness going on here. ..... Phil |
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