Nude Turntable Project

Halcro, I am happy for any (if any) role I played in inspiring your creativity. In our crazy hobby, everything matters and often it is impossible to figure out what does what to our precious sound.

Audpulse, Sorry but no pics available on this one. Here is my best info:
1. first why do you want to adjust the thrust plate - is there a problem with how the platter turns? If not then sit back and think about it some more.

2. if you want to go forward keep this in mind: the pressure on the plate is not random, not at all - if you get it wrong the platter either won't turn or it might make it harder for the table to get a grip and get spinning. Which I think might have happened to me.

3. The TT101 has a center screw that is easily visible and accessible from underneath once you remove the bottom can. To do this it is critical that you first remove the platter, then turn the tt upside down onto a bowl that is broad enough to sit stably as you work.

4. The center screw provides the pressure on the thrust plate. It is screwed in to an exact spot - don't forget that. It is also sealed with Loctite or some such sealer which you will need to scrape away and replace when you replace the screw.

5. Once you take out the screw you should replace the oil in the well - about 1/2 ounce will do. I suggest synthetic motor oil. You can wipe it out with a clean cloth. Careful in that there is a loose ball bearing sitting there and you don't want to lose that.

6. Reassembly is just that, but don't forget to seal that screw or your oil will leak out.

I hope that is useful to you. Questions?

I was thinking last night……because Aigenga’s TT-101 is nude and mounted on a wall-hung shelf like mine……I know exactly what it sounds like?
Same with Banquo’s ‘nuded’ Victor.
But I also know what most Raven AC turntables sound like (assuming they are not plagued by uncontrolled Structure-Borne feedback) and Rega Planar 3 turntables and Linns and Caliburns.
And if I was familiar with the big Micro Seiki 5000 and 8000 models…..I would probably know their ‘sound’ as well?

But I have no clue how a ‘re-plinthed’ SP-10 Mk2 or Mk3 sounds or how a re-plinthed Lenco, Garrard, Thorens et al would sound and I can’t imagine how anyone else can?
If every plinth can sound differently depending on material, sizing, construction, damping, resonance-draining and footers….how does any example sound like another?
And if they all sound slightly differently…..who decides which is more accurate and how is this decided?

From a purely objective and somewhat logical viewpoint…..if a ‘self-contained’ turntable like a direct-drive model (and to some extent Idlers) can perform their function without being encapsulated by a plinth…..why is it not reasonable to conclude that any changes to the sound resulting from the addition of a plinth is a ‘colouration’…an ‘addition’ or a ‘deduction’ or a ‘corruption’?

How do the ‘plinth’ advocates reconcile the fact that no two examples can possibly sound exactly the same?

Halcro.
You are using a plinth.
It is the shelf upon which your TT sits via the spikes you are using.
It would also seem logical that different shelf materials, size, shape, support method, spikes, et el would make a difference.

Richardkrebs,
I imagine it’s possible to ‘define’ an object into existence to suit one’s argument….but I’m not sure where it gets you?
To define a ‘plinth’ as a ‘shelf’ allows for a ‘rack’, a ‘platform’ and of course the ‘floor’ to also comply with that definition.
It gives us the situation where audio items like power conditioners and DACs and SUTs and preamps and amps are all on ‘plinths’?
And for those with a REAL turntable ‘plinth’ on a Minus K stand on a shelf on a rack on a floor……..we have a plinth on a plinth on a plinth on a plinth……..?

It would also seem logical that different shelf materials, size, shape, support method, spikes, et el would make a difference.

This would only be “logical” if one could conclusively prove that there was ‘stored energy’ within the shelf or within the object ON the shelf which REACTED to the “materials, size, shape, support method, spikes, et al” in a way that affected the motor, bearing, platter, record, stylus, cartridge and arm in a turntable system for example?
Despite the availability of accelerometers and other devices designed to measure and quantify vibrational energy and its transfer within materials…..I have seen no scientific evidence to support the many statements made by audiophiles on the nature of ‘vibration draining’ in regards to turntables….and any quantification of such?

The vast majority of audio systems are supported on the floor of the listening room albeit on racks or stands of some sort.
The vast majority of those floors are suspended timber frame or suspended concrete slab…..very few are concrete slab-on-ground.
All suspended floors (be they timber, steel or concrete) are under bending stresses of various magnitudes which create low frequency acoustic energy within the structure.
This low frequency energy (often resulting in movement) is transferred to the rack/stand/shelf supporting the equipment and results in higher frequency energy transmission and movement which is passed through to the equipment supported thereon.
With all this low frequency energy swamping the stands, racks and shelves……it is no wonder that differing methods of support and differing materials all have an effect on the transmission and damping characteristics?
But you are mistaken to assume that those who have absolutely no structure-borne feedback will also experience the same phenomena.
My floor is a reinforced concrete slab-on-ground topped with polished granite and is totally bereft of any structure-borne sound.
My turntables sit on a stressed-skin MDF shelf cantilevered from a masonry structural wall supported on that reinforced concrete slab.
The turntables sound identical whether they are sitting directly on the polished granite floor or up on the cantilevered shelf.
I have tested many methods of support for the turntables including an additional independent shelf on top of the cantilevered one….sorbothane feet, Delcrin footers, Stillpoint Ceramic feet, Stillpoint Ultra Minis, ceramic cones, aluminium cones, steel cones, plastic cones, brass spikes, steel spikes and stainless steel spikes. I have placed various materials between cones/spikes and the supporting shelf including metal coins, plastic, cardboard etc……and with all and every variation…..there has been zero change to the sound.
When there are no Structure-Borne feedback problems……there is nothing to affect the turntable adversely (other than Air-Borne feedback…..but that is another can of worms).
In fact a sure way to determine whether your room suffers from Structure-Borne Feedback is to see if changing the spikes, rack, footers etc results in an audible change?

But back to the plinth……I’m sure you have much to contribute to a discussion on a ‘real’ plinth into which a turntable like a DD or Idler may be mounted? :-)

Halcro.

We are both blessed with having music rooms that have concrete floors sitting on mother earth.

My definition of a plinth is likely a little wider than yours. To me it is.. "the structure that maintains accurate dimensional stability between the record surface and the tonearm". I am sure that you will agree that dimensional stability in this area is critical. I have also called this structure a "loop" in an earlier post.

By that definition your very nicely built stainless steel motor support, the shelf(or floor) and the equally nice arm pod are all parts of the plinth.

It would be reasonable to expect a change in the sound, if you were to change the stainless steel support for say a large diameter cardboard tube. Likewise we could expect a change in sound if the arm pod was made from say balsa wood. I suspect that your choice of these materials was based on experience and sound logic.
Since substitution of different materials would likely alter the performance, it can be inferred that your "plinth" does have a sound.