concrete (cinder) block tower with wood chopping block for turntable stand

@fjn04 I admire your adventurous endeavor in to creating a supporting Structure.

I do not intend on steering you away from this Support you are producing.

My thoughts on the materials used are that you have 3 x Stacked Concrete Blocks for the Lower Tiers with Voids (Unknown Dimensions but assuming 8.5" in Height). Plus 1 x Tier of 8.5" in Height Solid Concrete Blocks. 

What I suggest is, if I am understanding the materials used correctly:

1, Put in place a Base, that is mounted on a Damper Footer, (I avoid Spikes as a coupling to the Homes Structure).

2, My most successful Base to date has been a 1/2" Steel Plate, but at present do suspect better is to had (more later on this).

3, The Hollow Concrete Blocks can be Built up from the Steel Base.

4, Use Ceramic Tilers Cruciform Spacers to create the Spacing between the Base and individual Blocks.

5, There are very good quality Silicone Adhesives that are compatible with Stone.  A super bond can be achieved if a Primer Coating is used, prior to applying the Silicone Adhesive. ( For this Structure I see the super bond as overkill). 

6, Running a 1/2" wide line at the centre of the Blocks Side Wall's and Bedding the Cruciform Spacer into the Adhesive, will allow for a Nice Bedding and should avoid a ooze out, as the Spacer will prevent further compression of the joint. (If ooze out is occurring, it is best to learn the Adhesive Manufacturers Clean Up advisories, and have the Cleaning Kit on Standby. Usually a Soapy Water in a Spray Bottle, a Scraper and Wipes to Clean the Scraper is sufficient.

7, I would raise the Hollow Blocks to 4 x Tiers if the aesthetic is acceptable. (The extra height does work for the better when dealing with a Vinyl Source). 

8, Use Kiln Dried Sand to infill the voids in the Concrete Blocks, fill to a height, that is a 1/4" lower in level than the Top of the Top Tier.

9, Cap of the Void in the Concrete Block with a Material of choice. (Trialing Different Material is also part of the learning experiences to be had). 

10, The Cap Material will have a 1/4" Clearance all around the Void. The Thickness of the Cap Material can be of choice and is best if a Minimum of 1/2". Any Thickness up to 3" will be good to try out.

11, Think of the Cap Material as your first Sub Sub Plinth, and is to be built of.

12, The Footers to be seated on the Cap/ Sub Sub Plinth can be any type, this is where the learning starts, as this is where the first real impact on a sonic is going to be discovered. Is is also where the deselection process commences and the setting the structure to suit ones own preferences takes place.

14, The Sub Plinth will be best if immediately starting with a Phenolic Resin Densified Wood Board (The same Material I belief will supersede the use of my earlier mentioned steel sheets)

15, Footers used to separate the Source to the Sub Plinth, are again worth while trialling out of the variety of options.

My experiences to date are showing a 2 x Tier of Densified Wood, adds a very valuable impact on the sonic.

My suggestion is to live with each change to a Sub Sub Plinth / Cap or footer arrangement for at least 20 Hours of listening to really get the feel for the impact it has. It is not long before the desire to swap a material comes quickly when it muddies the Sonic and details and dynamics are noticeable for being masked.              

There are other suggestions being proposed for different mounting methods.

The Shelf is very useful, learning the options to securely fasten it to the mounting position is a Top Priority (mine is anchored using fastenings with a 250Kg Loading Capacity). Adding weight to a Shelf is a concern, but if all is prepared for properly the support structure will show a improved sonic with immediate effect.

I have used a Shelf for the TT, the Shelve has had Tiers added and had an alternative configuration where a Sub Plinth was Suspended from the shelf.

The shelve is no longer used for Vinyl as a Source, and is now used for another Source.

A Shelve has not enabled my TT, in my listening environment to perform as well as it does on a structure produced from multiple tiers and a variety of materials. 

When assessing a impact on the sonic, there are perceptions that are noticeable and subtle.

Usually when working with a Vinyl Source, the Bass is the most immediate to show a difference.

A Bass can have a looseness and presence to the point, the Mid's and Highs are being suppressed.

Working with a Structure can increase the perception of a Loose Bass, or Tighten the Bass, producing a cleaner edge and speedier decay.

Tidying up the Bass to have a Cleaner Edge and easier to define the speed of the decay, will also start to produce a coherence across the frequencies, where the Mid's and Highs are noticeably projected.

It is the toying with the improved coherence of the frequencies and projection, that allows for a tuning of the Soundstage, Width, Height and Depth are able to seemingly increased in dimension.

When the above is discovered footer changes can have a substantial or subtle impact on how this coherence is being perceived.

The next stage is more difficult as a compromise is usually required, a Trade Off is the only option, once the most attractive sonic to the users unique preferences is being discovered.

When the Structure is capable of resolving the perceptions that are being referred to above, analysis of the sound being produced, will also show Detail and Dynamics are present, and if the structure is produced to a type, that has a very effective interface into the listening environment, the Envelope of the Notes/Vocal will also be perceived.

Deciding on what is to be lost for the gain of another, is each to their own, 'What's your Poison'.    

When done to a particular standard, there is no returning to 'what was'.

When done to a particular standard, there is usually bewilderment wondering what would it take to better this, how much monies will be needed to have a assembly of devices that will improve on this.

My experience is that when a Structure has been able to show the above sonic is present, it is at this stage with Vinyl as the Source, that substantially benefits the  Tonearm that is in use. It might also be discovered through trials of other TA options, that the in use TA, is proving to be the weakest link in the Trilogy of Devices dependent on the supporting structure.

I ended up Swapping out a SME IV and AudioMods Series Five for being noticeably the Weaker, in comparison to the New Option discovered as a Performer.  

I am not condoning this proposed method as a ideal Structure.

I do not see where there is a ubiquitous method to produce a structure that offers a support that stands out for the impact it has on a System and especially the Source. It is good to see one contributor has produced similar and has reported on the value of it in use. I again suggest a Phenolic Resin Impregnated Densified Wood Board to be tried out as a Sub Plinth/Sub Sub Plinth.

I see the proposed method as affordable and a good place to commence with an investigation into producing a Structure, any changes that may be discovered to be worth making, will mean, if the Blocks are to be selected for exchanging there will be little concern for the initial cost of the items.

Some decisions to make changes are costly, especially when certain Footer Types are be exchanged out for others, there is concerns, when swapping out items with high prices to perform a identical role.  

I have a history of using Concrete Blocks and Sand Filled Boxes, I have good recollections of these in use, but have found methods which have produced a sonic that has superseded these, which has resulted in certain methods being no longer in use.

Additionally, I have tried out and remain using other Stone materials. I have also  been through numerous types of Board Materials and Sheet Material with a wide variance in their Densities, of which I have a few types that I will always have at hand ready for use.

Again for Vinyl as a Source, In conjunction with the above, I have a selection of Platter Mats, of which Four different materials are always at hand and being considered for how they can fine tune the sonic.

I have never used a Bespoke State of the Art Design Supporting structure for a Source. I know of some models and up to £5K can be spent.

I don't know whether my efforts fall far short, are parity or surpass such a device.

I do know for approx' a 1/4 of this cost across many years of learning, I have a supporting structure that works very well for me in my listening environment.

Tomorrow, I will be visiting a Home of a infrequent attendee of my local HiFi Group, and will be demo'd a 'New to Me' System. 

I will be taking along a few electronic devices, as well as  Two Tier Densified Wood Sub Plinth, with a AT-616 Footers as separators. I am really looking forward to day out, as well as witnessing the system owner hear their Source mounted on this assembly.    

Anything that is Skeletal in appearance, will be a harder sell to others if not wearing a pleasing aesthetic Jacket.

There is a honesty to such a structure as under discussion, and if wanted to be a keeper, the very basic appearance, can very easily be concealed. It is really down to how much cost os wanted, and whether meeting such a cost, will then create a situation where the cost, will enter into the area where other options are also able to be considered, and certainly be a sellable item when no longer used.   

Some say this individual, is the Godfather of Isolation Ideas, even the earliest Townshend designs are claimed to be versions of this guy's proposals.

Worth a Read, and the Ball and Spoon works to certain degree in all the guises seen.

Quite a few years ago I was to experience the Ball and Spoon and a selection of variants of the method, all will impact on the sonic, Metal on Metal is cheap and very good starting place. 

Not that I have tried it, but today, I will suggest Densified Wood on Densified Wood will be a very interesting footer.  

Some versions seen today of the Ball and Spoon method are the best part of a $100.

http://www.barrydiamentaudio.com/vibration.htm