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Scott Dorsey Scott Dorsey is offline
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Default Turntable "suspended in a vacuum" to prevent vibrations?

George's Pro Sound Company wrote:

but if the magnets vibrate would not the change in flux vector cause a
vibration in the suspended object


Yup! Magnetic suspension is hard to make work properly.... you need to have
a constant flux over a wide area so that if the base vibrates, the field
at the plinth magnets doesn't change much if at all. You can make it work
but it's hard to make it as effective as cheaper alternatives.

On the other hand, those cheaper alternatives ALSO require some careful
engineering and they don't always get it. I can think of a mastering house
in NYC that was having trouble with building vibration from the subway and
installed a fancy isolated platform whose suspension had a resonance around
0.5 Hz which would get excited into wild motion by the subway....
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."