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Saw a turntable stand in Acoustic Sounds that uses repelling magnets to suspend the table in mid air and shield it from vibration . Anyone have any experience with this product or one like it? Specifically, would magnets (presumably a set of four) strong enough to suspend a 40- or 50-pound deck pose any threat to the magnets in a cartidge, or other components.Would think this might be a fairly cost-effective DIY project, if one could solve the problem of the top platform flying off to the side because of the repellance of the lower once (presumably, it could be contained in a simple frame - four corners -it wouldn't even have to be a full box).
Follow Ups:
I just love all the negative responses which have been posted.My only wonder is how many of the people who responded negatively have actual experience of a mag/lev product?
Hands-up everybody who responded negatively who has had hands-on experience with a mag-lev product.
I use a SAP Relaxa 3+ under my turntable and experience no negative effects whatsoever.The platform made a beneficial change and will remain in place.
Not cheap,but I've tried air bladders,and basically they work but they piss me off with the difficulty of maintaining stable level.
Yeah I know it can be done,but I'm also done with air bladders.Been there,done that.
How many naysayers on this thread can say the same about Mag-lev?
The SAP has a max load carrying capacity of 25 Kg or so.
I'd like more info from the gent who has developed his own version.
made in the 1970's, used opposing magnets to float the platterI own a belt drive magnefloat, works fine, no negative comment here
Picture is the Direct drive TN 400 from circa 1976
I've never seen one of those, but I'd love to score one.
... no, I haven't played with it first hand, the principle of magnetic levitation is unsound enough in theory (to me) that it is not worth the investment.What appears unsound? A huge magnetic field directly underneathe an extremely low level pick up device.
If your WXYZ magentic platform "works for you", great.
But no thank you for me.
I ptobably like my eggs different than you, too ...
and your definition of negative is???
I have booked a seat on a Russia space flight to check out a none gravity suspension. I will report shortly.
Anything with substantial compliance can be used to absorb vibrations. It really doesn't matter if it is springs, air, magnets, bearings etc. There are two factors that determine the attenuation of vibration. The resonant frequency of the suspension and the damping of the suspension. While damping a suspension may seem like a good idea and a lot of people want the suspension to stop resonating ASAP it actually hurts the suspension's ability to attenuate vibrations. Oh, the lower the resonant frequency of a suspension the greater the attenuation. I wouldn't touch a DIY magnetic suspension system. Springs, bearings, elastomers and air bladders are all much easier to work with.
Let's see, we have a low output cartridge just inches away from rare earth magnets ... strong enough to levitate a turntable chassis.Sure, folks can talk about shielding, but ... no thanks.
Of course I don't know if the Continuum Caliburn is the best but Fremer thinks it is and I do find him reliable. You may demur of course. Anyway the magnetically levitating stand is part of the deal. And it supports one hell of a weight.In the UK we have the Lumley Stratosphere TT which got rave reviews upon its introduction and uses magnetic suspension. It has just been reintroduced. This suspension has been sold or licensed to Clearaudio.
There is also an Italian magnetically suspended equipment rack or rather mechanical interface (name forgotten) that is used by some friends and also has uniformly good reviews (for what it's worth). Maybe it's the one that you saw.
So I have no personal experience but the principle seems to have a good track record.
It still need solid contact with the bearing, and I think this is important for draining off vibration and having good stability, I am thinking of doing this with my Teres clone
.
Be careful not to confuse a bearing with a suspension system. By the way it doesn't even have a true magnetic bearing. It just uses it to ease preasure on the bearing.
thrust bearing, so the magnets do considerably more than "ease pressure on the bearing".
http://www.jcverdier.com/leaflets/GBPDF/PLATINE_VERDIER_GB.PDF
Magnetic levitation affects the coil of cartridges (and cantilever in many models), and royally screws with tracking if you have a metal tone arm. Moreover, metallic impurities in older vinyl can create havoc. All-wood design solutions, especially those featuring the beautiful hand-carved styli of exotic hardwoods from the Amazon, are elegant but sadly inefficient, requiring extraordinarily powerful step-up stages.So I prefer the antigravity approach to turntable design. Unfortunately, this technology is so secret that, if I even told you where to ask about it, I'd have to kill you.
nt
I believe antimatter is what they used for the engines. Not that I'm a trekkie/trekker or anything, but all antimatter would do for you is explode upon contact with matter. :-D
Don't know how it would do for draining vibrations from the turntable and platform itself.
We are on the same page. I bought 3 pairs of Neodymium superstrong magnets OD 2"X ID 1" X 1/4" on e-bay for $72. I put each pair on aluminum axle such as the lower magnet is sitting straight on its shoulder, and the upper one contacts the axle through two rubber O-rings. The rings are taking lateral load, centering one magnet against the other and damping lateral vibrations. The upper magnets bear the sandbox through aluminum cups. The axle lower threaded end of 3/4" is inserted into the hole within massive supporting shelf made of three 0.5" plywood sheets glued together, and fixed by means of two aluminum nuts, allowing the sandbox precise levelling. This platform can bear my own weight (75 kg), still leaving about 1 mm gap between magnets (verified). Work is in progress, I will report about results.
If you are interested in drawings, drop me e-mail.
If the repulsion is so strong, you'd have to take very great care in handling them to make sure the attractive faces never got near each other, or I imagine you'd never get them separated again. I'm curious how something like this could be shipped, with such huge forces between them. How did the seller pack them? I'm interested as I just had the difficult job of rebuilding a Wharfedale tweeter, which involved arranging one magnet coaxially about another with a very small clearance between them and a fairly forceful attraction between them. Not as violent as yours, but very difficult to handle - it took me some time to work out a way of doing it.
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