Concrete Slabs

As crazy as it might sound, one of the most significant improvements I achieved whilst going through the various permutations of materials to produce a Structure to support the TT.

Was discovered when I placed a Steel Sheet of a Dimension 1100mm x 750mm x 15mm as a Base Plinth to Build the Racks onto.

It is a 'young mans sport' getting the Steel Sheet into place, but the recollection of the change that occurred one the structure was once more assembled was quite indelible.

The Steel Sheet today is rested/attenuated on Footers, which ended up being made up of Granite with a Cork Pad as the Base and a hard foam in between the Granite and Steel Sheet.

This is not too expensive to achieve, even if the Steel Sheet was to be cosmetically finished.

Creating a Structure to mount a sensitive item of equipment on is a Topic that will appear the more it becomes understood how the impact of the Ambient Environment on the equipment can be detrimental to it.

There is no harm trying out additional Tiers of Supporting Structure, between a TT and Table Top.

The New Addition of Materials and added levels of Isolation will bring something new to the perception of the SQ.

An assembly for a Support Structure is likely to be discovered that will surpass what is already in place.

It is the trialing of Support Materials and Isolation/Separation, that helps one determine where their objective is best served.  

Does a $4K Vibration Control Platform offer much more in control, than a well thought out structure that can be produced for a considerably less cost, or is the $4K Platform a shortcut to a Support Structure that can be mimicked using other types of Structure as a support, only Trials will assist with learning this.

As for the Oak Table a very affordable trial could be to utilise Newplast Modellers Putty. This can be used between the Oak Table Top and have a Sub Plinth Tier, seated on to it.

This as a method is now offering Two additional Materials as Tiers to create a Sub-Plinth, and can have a very valuable effect on the Damping Factor of the Structure and improve on the Dissipation of energies being transferred. 

At the present, I am convinced that Phenolic Resin Densified Wood offers a performance due to its properties, that is proving the most suitable for use in a structure.

A TT Plinth or Chassis, Sub Plinth, Speaker Cabinet Baffle or PCB are all today being produced using this type of material.

I have over a period of time had Birch Plywood, Compressed MU25 Birch Plywood and Panzerholz demo'd on same TT > Tonearm as the TT's Plinth. The Densified Wood as the Brand Panzerholz has shown to be the most attractive in use.

I have also been demo'd TT's and CDT's in use with a Panzerholz Sub Plinth Structure and again the noticeable attraction when the material is used is notable.

My in system testing is in the early stages, but there is already enough evidence discovered and attraction created to leave me of the opinion, that selected materials over the years are now most likely to be superseded. 

The following links will show where the Densified Wood such as Panzerholz and Permali are showing their differences in properties for damping and dissipation to other more commonly selected materials.

 https://qualia.webs.com/newdampingfactors.htm 

https://www.lessloss.com/page.html?id=80

I have not heard @dogberry's System or set up for his source.

I am certainly not qualified to inform him his set up is correct.

I am with experiences that the outcome has been quite beneficial, even if only assessed as subjective evaluation. There can be no harm in suggesting to the OP that a reconfiguration of the support structure in direct contact with the TT, can create a performance from the TT, that is perceived as for the better.

One advocate of this type of practice has already put the idea of suspension forward.

I have found adding Tiers to a Structure and using certain types of Separation/Isolation Footers between the tiers has proven to be a very valuable inclusion.