Vibration Issues / Turntable Decisions

Fixing the deflection in the floor from underneath is not that difficult, its the choice that requires a bit more effort in a shorter time span physically ,but it is THE only choice that  removes the problem.
All others are band aids that somewhat work at varying degrees , and at differing degrees should you change the table or the rack.
A solid foundation will always give better results and cost less and take less time to do where access is available,  than the hours of work it takes to earn to save for an inflated , retail band aid to solve an easily solvable problem, not solved at all but just masked with band aids.
No brainer for me, a Saturday morning and its over, free to have any table, rack or speaker, stand mount or not with greater choice on design and function and cost.

Yep, 100% right on. Going to take some time this weekend and investigate some options under the crawl. I only have 2' of working space between the bottom of the floor joists and the earth below.

Stay tuned!

roxy54
I said decoupling not damping.

I was responding to the poster previous to my comment. I am pro decoupling and pro draining and to a lesser extent pro damping. In combination, not separately.

hifiron,

My crawl space has less than 2'. I ended up using some 4x4s and some 20 ton bottle jacks to support the floor joists.

When I was a postdoc at U. Oregon I was introduced to atomic force microscopy, a technology that uses a stylus in the sub-micron tip size range to physically scan and touch-tap to map and image the topography of biomolecules such as DNA, proteins and other structures on a solid support. The resulting images showed hi rez, three dimensionality of biologically relevant tertiary structures. An example was propogation of RNA polymerase II on a DNA template in solution. As you can imagine, any vibration needed to be removed from the microscope and detection system in order to gain maximum resolution. The solution was to suspend these microscopes not with mass loaded heavy laser tables, but with bungee cords from the ceiling.

I don’t see why the same physical principles couldn’t apply to turntables.