A Copernican View of the Turntable System

"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."

What a vacuous discussion. Suggest if you believe this, then sell your turntable, motor and records and just listen to your arm.

Your statements above contradict themselves - for ultimate speed speed stability there must be no movement between the drive and the platter. For ultimate generation of music from the interaction of the stylus on the record, then there must be no movement between the arm mounting and platter.

Ergo the motor drive, platter, arm and cartridge must be coupled together in a closed loop system that is absolutely rigid and yet has no transfer of unwanted energy between them that smears the speed sound or whatever.

In fact there should be no cantilever suspension to ensure as much transfer of the signal as possible - much like a rally car where they remove all the rubber mounts in for the engine, gearbox, drive etc to maximise power to the ground.

Interesting views.
Most think, that a Turntable, no matter which one, is a perfect unit and every manufacturer has enough knowledge to make it in a way, that it can't be improved. That is a master mistake.
The combination cartridge/Tonearm is hugely overrated, more or less the calculation (resonance) is a waste of time today, different Arm Tube materials, also because there are features, which are much more important for reproduction (Bearing quality, Geometry, energy transfer, ability to guide a cartridge, absence of ringing....)
The Armboard is a really interesting kind of view, Never discussed before. And very important. The best Arm can't show its abilities when the resonances from the Turntable are reflected in it. Same the other way from cartridge.
Or both sides are added and the search of the right cartridge will never end :-).

Turntable chassis, motor drive (idler, direct, belt), bearing, platter, armboard, tonearm, headshell and cartridge make an analogue playback system - they are a unity and do influence each other. Looking on separated or single parts or combinations of parts will not help in the end to improve the overall capability of the system.

Maybe the importance of different plinth designs was a little overrated in recent developments using idlers or DDs and putting them into plinths of slate, special wood or other material. Many TT-designers did a good living by doing so. I do understand that audiophiles are getting a little tired of the plinth approach and switch to the other extreme. Focusing mainly on
tonearms and cartridges might be another misleading direction. Indeed we should concentrate on geometry, isolation where needed, careful installation and the quality and flexibility of armboards used.

Micro Seiki uses armboards made of brass which are very rigid and do enable the user to match all requirements in terms of geometry. Other brands of today have copied this philosophy - this is fine! But how many audiophiles are stuck in geometry problems when it comes to mounting a new tonearm. Sometimes one has has to build or order extra armboards
which are insufficiant.

A system should stay stable, free floating armboards bear risks of instable condition, especially when they are not real heavy weights or not placed on a special position on a special platform.

Dear Halcro: I see.

+++++ " I am claiming that without the precondition of the immovable and isolated tonearm BASE, any tonearm/cartridge combination will be compromised to some degree. " ++++++

well over the time at least five times I claimed the importance and influence of the arm board in a cartridge quality performance. I did not claim exactly what you are doing.

Now, there are some different subjects on your statement and I will try to comment by separate:

++++ will be compromised to some degree. +++++

IMHO from the very first moment that we mount a cartridge in a tonearm headshell exist a compromise between ( at least ) the cartridge body resonance point against the headshell kind of build material that has its own resonances.
From this very first stage all what happen between the cartridge, tonearm and TT is full of compromises including our each one skills to overall cartridge/tonearm set up even room temperature is a " compromise " on cartridge quality performance level.
Certainly the arm board link is an additional compromise with its own trade-offs.

Isolated BASE: well this IMHO is a TT manufacturer responsability where the tonearm manufacturers has to deal with.
In this regard I'm a proposal of stand alone arb board towers for at least all the TT resonances can't transmit through the arm board or if the TT manufacturer prefer the arm board integrated then that will be isolated from the TT it self.
In either way the TT manufacturer has to take care that the arm board be self isolated someway for the UNIT can't be disturbed by this audio link.
As other subjects/factors in audio this arm board base isolation always is desired but till today never achieved.

In the mean time IMHO the best a tonearm manufacturer can do is try to isolate the tonearm it self from the arm board.

Problem with this thread subject is that normally the TT manufacturer is different from the tonearm one and IMHO even if both were the same each manufacturar/designer thinks and fix his priorities in a different way with different targets.

Other aspect on all these is that the cartridge quality performance level on playback is surrounded by a lot of different an important factors where the arm board is only one more. Where can we put on importance level the arm board base subject? , this could be very subjective because we have to rank all the factors that have any influence in the cartridge performance and determine the precise " weight " each factor contribute against cartridge quality performance playback level.

I don't know for sure where you want to arrive with this subject and the only thing I can tell you is that some one has to take care about with more care that the one used too.

Regards and enjoy the music,
Raul.

Copernicus was a twit anyway.