Racquetball isolation platform perfection

Bombaywalla,
Can you provide any scientific study or evidence, any physical or acoustic principles or formulae which correlates the 'knuckle rapping test' with the behaviour of 'real-world' acoustical feedback?
I see many audiophiles who place great importance on this dubious 'test' and have seen no evidence of its relevance in scientific terms?

04-22-09: Halcro
Bombaywalla,
Can you provide any scientific study or evidence, any physical or acoustic principles or formulae which correlates the 'knuckle rapping test' with the behaviour of 'real-world' acoustical feedback?

I don't have any evidence at the time of writing this post so you are free to dis-regard my post re. the knuckle rapping test & carry on w/ your life.
I'm afraid that I do not have scientific evidence, etc for every tweak that I do. If I were a man who did every tweak only after I found scientific evidence I would most likely not be in this hobby. Many things that we obsess on in audio have not or cannot (due to our inability to measure the exact parameter) be explained. And, of course, there are many other things in audio that do have a scientific background.
So, if you are the kind of person who wants evidence before even considering a tweak, then, the test I suggested is not for you.
My rational for the test was that knuckle rapping manually & forcibly excited the resonances in the rack, shelf, sandbox, plinth, platter. These resonances could very possibly be excited during the course of vinyl playback, couple to the TT, be picked up by the sensitive cartridge & be heard thru the louspeaker. I do not know how loud the music would have to get or how much vibration would have to couple into the rack for these resonances to be excited but, intuitively, the harder one would have to rap on the rack/shelf/plinth/sandbox the louder the music would have to be for the resonances to be excited & for them to be coupled to the cartridge & heard thru the loudspeakers. Again, intuitively, harder the knuckle rapping in order to hear it thru the loudspeaker, the better the TT isolation. The goal is to get to the point where none of the knuckle rapping is heard thru the loudspeaker & apparently, from talking to a few people, this is possible.
From the viewpoint of available commercial TT products, I can see this in the implementation of the top-of-the-line offerings from brands like Goldmund, Rockport, Basis, VPI, Teres & Continuum.

Knuckle rapping and raquetballs are sooo 80's....
I thought I was reading a back issue of Audio.
Come on, guys, progress a little, will ya?

04-23-09: Chashas1
Knuckle rapping and raquetballs are sooo 80's....
I thought I was reading a back issue of Audio.
Come on, guys, progress a little, will ya?

you are like Wall Street that thought since they were in 2008 (modern times, the time of information age, etc, etc) they could we-write the fundamentals of finance. You can see where that has brought us today.
You want "progress" for the sake of progress even if it brings hardly anything new to the matter on hand. IMO, that's not progress; it's B.S.
The turntable design has not changed in multiple decades only the quality of materials have. The same old fundamentals apply to its proper design & functioning & I believe the same old tests apply to testing its isolation.
And, I think that you are simply being an antogonist (with a zero contribution to this thread)!

LOL!!! most of my gear is from either the 70s or 80s so I guess I'm just a retro kind of guy.Some people also call this old age.
I guess I will just sit back in my mid century Danish chair and sip some more single malt while I rap my knuckles on the table.

e