Suspended vs. Non Suspended TT on Concrete Floor


Am considering purchasing a Clearaudio Reference or Master Reference table that would sit on a large Polycrystal amp stand. The stand will sit directly on a carpeted concrete slab basement floor. The speakers, which are about even w/ the turntable are about 9ft. apart (4.5 from the table). Would the high mass/weight/coned design of the Clearaudio tables need, or benefit significantly from, further isolation like a Vibraplane or other like device. Your advice is appreciated.
fbhifi
in my view, you would degrade the sonics of either of the clearauido tables with the use of an isolation device like the vibraplane. the suspensionless design should work perfectly on a rigid/high mass stand placed directly on concrete through a good set of spikes. it would be better were the tt farther from your speakers but we all must compromise. BTW, there will shortly be offered a new clearaudio model between the reference and master reference. it will have 3 motors but be only 2 "layers" high, rather than the 3 of the master reference. -cfb
The best set up I've heard is highly WAF unfriendly. Sounds like you may be setting up in a basement; if you can get away with it pour a 4' high concrete pillar directly coupled to the concrete floor. The large Sonotubes and half a dozen bags of premixed cement will do the trick. Isolation at it's best? You betcha! A little extreme, maybe, but most of us aren't entirely normal.
Jeff, what is a sonotube? I have the same situation and may try that approach.
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