A Copernican View of the Turntable System

For thousands of years it was believed that the earth was the centre of the solar system and that the sun revolved around it.
Before telescopes existed, Copernicus proposed that it was the earth in fact, that revolved around the sun.

For longer than I can remember, it was generally accepted that the turntable (plinth/platter) was the centre of the analogue playback system with the arm and cartridge attendant to it?

I propose that it is the arm…..or rather the cartridge that is in fact the centre of the turntable system with the platter required simply to drive the record onto the stylus.

Together with the belief that the platter is the centre of the ‘Turntable System’ is the belief that the stylus ‘tracks’ the groove in the vinyl in a passive subservient manner?
I propose that it is the platter which drives the vinyl groove onto the stylus which is being held rigidly by the tonearm.

Imagine if you will in a perfect world, a cartridge held in a vice-like grip and a mile-long, perfectly straight vinyl groove being fed at precisely the right speed past the stylus?
All that would be required for the cartridge to transmit perfect information, is the ability to move up and down frictionlessly to allow for warpage as the groove modulates?
Now this ‘straight’ vinyl groove is in fact a ‘spiral’ so that the cartridge must have the ability to adjust its position laterally also in a frictionless manner.
That is the purpose of the tonearm……to hold the cartridge rigidly yet allow it to move up and down and sideways as the vinyl groove is rammed onto the stylus at a perfectly maintained constant speed.

The tonearm is now the centre of this ‘Turntable System’ and is the most important element. It must be rigidly held on a base which is perfectly flat, non-magnetic and relatively immune to structure-borne and air-borne feedback. This base must ideally have no contact with mechanical or electrical interference and must under no circumstances, move or deflect in any manner.
This base should ideally have no contact with the drive mechanism of the platter or the plinth, sub-platter, belt, gears, idler-wheels etc.
This base should be an island.

The ‘turntable’ or platter is simply a revolving mechanism positioned at a certain geometrical distance from the centre of the tonearm, whose method of drive has absolutely no impact on the sound of the ‘system’ so long as it maintains perfect speed control and perfect isolation to the record from air-borne and structure-borne feedback.

The idea therefore of a plinth around the platter in the above scenario, would only serve to add or subtract information in a worst-case scenario, or be totally transparent in a best-case situation.

There……I’ve said it.
Is there a 'Galileo' out there to support me before I die unrecognised? :-(

Interesting thoughts. First, though, a question: How did you end up getting the long post accepted after first having had it rejected?

Ummm.... First you posit a "new" way of looking at the interaction of cartridge, tonearm, and turntable which I think is leading to a defense of outboard tonearm pods. But at the last second, you swerve away from that issue and seem to posit that your Copernican view of the LP playback system somehow leads to the conclusion that a plinth is superfluous. As Archimedes might have said to his plumber, "It does not hold water".

As I have said before, the plinth issue and the arm pod issue are two entirely separate ones, except whereas the lack of a plinth makes it easy for you to get a bunch of tonearm pods nearer to the platter, so they can all be aligned properly. I don't think there is any argument that can lead to the universal conclusion that a plinth is never a good idea or never leads to a perceived improvement in LP reproduction. It is even conceivable that a good plinth can be more than just transparent; it can make the turntable (idler or direct drive) sound "better" than it does with no plinth. (Before I abandoned the belt-drive notion, I had come to the conclusion that for belt-drive, a big heavy plinth was superfluous and usually not a good thing. Most of the top end modern belt-drive tts seem to be built in accordance with that idea.)

I do think there are good arguments as regards independent tonearm pods, pro and con. I have stated my argument against them elsewhere, more than once. Here you have an interesting argument for.