A Copernican View of the Turntable System

How big a Problem Is this Airborne Feedback ?

I am referring to 95 + db levels at the listening position.

Or is it really structure related so a wall mounted TT would work best?

Two statements made on this thread.

Halcro

Air-borne feedback is very rarely a problem despite what you believe.

JCarr

Even better would be to add an acoustic shield around the turntable so that it doesn't get affected by the sound pressure from the speakers.

Are these not differing viewpoints?

Hi Johnathan Carr - is your statement based on your real experience with ”shields” or theory ?

Hi Henry – I know you have yelled at your cartridge at a loud decibel and not heard anything back through the speakers ? Do I really need to attempt this as well ?

I rotate different speakers into my room - Dipole, Dynamic cones. Gear placement for one type does not mean the best placement for the other especially if dealing with a smaller room.
I have opinions but would like to hear others real experience. I am planning some modifications to the room. This discussion would be very helpful to me.

Cheers

Chris

Hi Chris,
I get more feedback when I yell at the dog than I do from the cartridge :^)

On a serious level.......it is often difficult to isolate 'structure-borne' feedback form 'air-borne' as the 'air-borne' feedback can be absorbed into the equipment rack or floorboards and thus mutate into 'structure-borne' feedback affecting your system.
If the feedback increases as your volume increases.....this can identify the problem.

Halcro,
What does it mean if the feedback increases as volume increases. If airborne feedback is the ONLY problem, one would figure the effects to increase. Personally, I am not convinced that airborne feedback affecting my rack, and then feeding 'structural feedback' through an isolation system (designed to combat structural feedback) to my turntable is a more insidious problem than the same airborne feedback affecting the record, tonearm, or dustcover itself.

In testing now...

my thoughts on airborne feedback. i believe it to be real, but difficult to identify. what i did to minimize it was to minimize the surface areas that could absorb airborne vibrations/waves. i did this by building a "nude" rack. i eliminated side panels and shelves and rest my equipment on the frame itself. i also incorporate alto extremo feet to absorb and isolate.
for the equipment, such as tables, that would not fit onto a nude rack, i made isolation platforms for them, filled with dense steel shot. that way, any airborne waves would have a hard time moving the heavy weight.
i have to update the pics in my gallery (actually, i thought that i had done that!!).
don