Suspended vs. Non Suspended TT on Concrete Floor

herman: sonotubes are hollow forms made from heavy layers of paper/cardboard that are used to construct concrete piers. you can get em' at most construction supply stores. BTW, if you were actually to engage in such a project, you would need to anchor the piers to the slab. i'm no construction engineer but i'd look to using long bolts drilled into the slab and fastened down with appropriate hardware. -cfb

Before you pour the concrete you may want to consider my experiences. Reinforced concrete does have a very noticeable resonance. That is why industrial labs use fairly elaborate vibration control engineering in critical applications and don’t just use poured concrete
When I was doing earthquake retrofit, I poured some large concrete piers in the crawl space to disconnect my Dunlavy SC-V's from the wooden floor in the listening room to control the floor resonance. By moving a simple vibration detector (water in a shallow bowl) over the concrete below I could detect the standing waves caused by the speakers resonating the concrete, primarily through the reinforcing rods. There were definite null and reinforcement points. Your basement floor was probably reinforced with mesh so your resonance might be less, particularly if you spike your speakers.

However your reinforced poured concrete pillar will still have a very definite resonance, which would be a bad thing for a turntable stand. It might not matter since it would be difficult to calculate in advance. In my case the fact that the concrete sub floor vibrated didn’t really matter. I was just curious about the resonances. Once I substituted oak bracing for the metal floor jacks that I started with, the vibrations were significantly damped. BTW, separating the Dunlavy’s from the wooden floor made a BIG difference in the measured and perceived sound.

The concrete floor is a good thing for either suspended or a
non suspended turntable.
My recommendation is not have anything between your speakers.
This is where bass builds up in a system.
Having a rack between the speakers also effects imaging and depth of stage.
I prefer having all components except for the power amp on a side wall, using short speaker cables if possible and running long interconnects to the preamp.
This will work fine as long as your preamp can drive long interconnects.
Some tube preamps do not have a cathode follower and would not be recommended.
Hope this helps!
Best regards
Larry
Hollywood Sound