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In the Forum: Analog Playback
In the Thread: Ultimate Turntable
Post Subject: How good does it need to be?Posted by rowuk on: 4/7/2020
 noviygera wrote:
Not that physics is my strong suit, but casually watching a physics youtube video this thought crossed my mind.
I wonder if gyroscopes can be used in a turntable to improve it's performance without reverting to ultra high mass systems to maintain a good level of stability?
Take the platter for example: If the mass of the platter is concentrated at the perimeter, it will act as a gyroscope while spinning --- this is obvious. What's not obvious to me is what that min velocity is for a given mass platter (that is built like a gyroscope, with most of it's mass at the perimeter) to reach precession. Is this achievable at only 33 or 45 rpm?
Could this be why 45rpm records sound better?

Well, the platter can act as a gyroscope in itself, without any additional contraptions! Is it only a function of the perimeter mass?
However, with external gyros, maybe it would make sense to stabilize the plinth? The tonearm?

I am not claiming any new discoveries, but wondering if this fundamental law of physics can be applied more intentionally to improve the mechanical device "the turntable" to achieve better performance without the need to build the high mass monsters that I have seen. 


Considering that the master recording probably has more "error" than modern quality playback, what does "better" performance mean? We have rotational stability and low/tailored noise floor as far as the turntable goes. With the tonearm we have a resonant system with little "engineered" ability to manipulate the resonance. We need clay, silicone caulking with lead shot to "improve" assuming that we have ears and a brain.
For sure pitch control is one of my major needs. It is amazing how many recordings are not at the originally recorded pitch (yes, we know how many of the top orchestras tuned throughout recent and not so recent history).

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