It never ends...
"After a full spin, the heavy vinyl landed on the DeMag for a degaussing session. Both sides got treated and then it was back to the Thorens."
"After a full spin, the heavy vinyl landed on the DeMag for a degaussing session. Both sides got treated and then it was back to the Thorens."
For completeness and fairness, here's the rest of the text:
A professor Henry A. Rowland working at the John Hopkins University in the late 1870s was send to Europe for studies of laboratories and instruments. On his tour he met and studied with Hermann von Helmholtz in Berlin. Here he found the time to finish his study of the magnetic effects of a charged rotating disk. At that time, Maxwell’s equations on electromagnetism were the subject of heavy debate. Rowland’s experiment was difficult as it demanded extensive mathematical calculations as well as measurements at the edge of detectability but Rowland pulled it off. The experimental setup consisted of a disk of hard rubber or an old phonograph record connected to the shaft of an electric motor.
The disk was given an electrostatic charge by rubbing it first with a piece of woolen cloth. Then the disk was spun and a magnetic compass brought in close proximity. This deflected the compass needle. The faster the spin, the greater the deflection. It appeared that a magnetic field got set up not merely by a current moving through a wire but by a moving electrostatic field as well. Rowland’s work, the first demonstration that a charged body in motion produces a magnetic field, attracted much attention.
So what do we have here in our modern time regarding CDs, LPs and the Furutech DeMag? We have a medium very much prone to static build-up. Thus charged, we spin this medium at up to 500RPM for CD and a bit slower for vinyl. From Rowland’s experiments we learn that such activity creates its own magnetic field. With magnetisable particles embedded in the CD structure, label print ink and colorants to make basically clear vinyl look black, we have permanent magnets on our hands. For LPs, the magnetic field of the spinning disk is in very close proximity to the sensitive structure of the cartridge and thus influences the pickup. And because CD processing is for the major part analog, something similar happens there too and is additionally powered by faster revolutions. By degaussing and thus applying an opposite magnetic field with the DeMag, the disc’s static magnetic field is lowered enough to make an audible difference. By playing, handling and restoring the disc to its case or sleeve, the disc is being recharged. As we learned from professor Rowland, this is the necessary condition to recreate a magnetic field when the disc is spun again. That field causes the ferromagnetic parts to get re-magnetized to create the need for another DeMag session later
someone needs to think about Relativity to relate where moving charge is seen as mag field - and where the charge isn't seen as moving
antistatic treatment/charge removal is lots more justifiable for Coulomb Forces
of course thinking about Relativity gives much more scope for audiophool ad copy - do I need Lorentz transform pitch correction that varies as groove speed?
antistatic treatment/charge removal is lots more justifiable for Coulomb Forces
of course thinking about Relativity gives much more scope for audiophool ad copy - do I need Lorentz transform pitch correction that varies as groove speed?
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"measurements at the edge of detectability"
"The experimental setup consisted of a disk of hard rubber or an old phonograph record connected to the shaft of an electric motor. (room fan)"
Not mentioned was a pocket compass to detect the effect.
So a spinning charged disk creates a field comparable to the earth's, how about 33 1/3 rpm and less static? Any numbers on the residual magnetization at these levels and the impurity levels present? The highlighted "both sides" comment was to point out the basic lack of understanding going on here.
Proof please!
Assuming uneven static charge distribution.
Nice story. Alas, there is no disk’s static magnetic field to degauss. There is only disk’s static electric field.
George
In one of the more extreme static conditions I've had, the tonearm lifted right up off the charged record. It didn't help that I also use a felt mat.
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Wait , what, the Dust cover .....
I think the LP and dust cover static charge fight it out, the dust cover is just too close in this case. I think it is pretty easy to show that the electrostatic effects when playing LP's are orders of magnitude larger than the magnetic ones. I wonder how MF keeps his stylus rake angle at 91.117 degrees?
Sound like a story . Any one willing to pay 10.000 pounds and the 3 years an other 90.000 pound on two machines is telling a story that I don't believe. Correct me if I am wrong but is not a council garage a local government storage building why would any one pay 10.000 ponds for 2 dead tape decks ? From what I know of stamper and vinyl production 300 is a very low number 5000 is a pristine amount from a stamper when done at a moderate rate. 2.500 pounds is for status so to drive up the demand . It keep the rifraft music lovers from owning them.
MF Uses zerostat on his records , heres another demag pro-forma ..🙂
http://m.youtube.com/watch?v=1TkJ_wwkbNA
Yes he is. Closed the Mastering lab in Caly thou .
Strange , supposedly there's a 6 month back log of work currently for mastering suites ....
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