Racquetball isolation platform perfection


Racquetball isolation platform perfection ... and DIY style to boot ! Thought I'd share with you my experiment that turned out working perfectly in my system.
Basically I copied a Ginko Cloud platform using $5 worth of racquetballs from Wal Mart and some 1/2" Birch plywood. I used a specialty grinding stone from a local tool store that makes a perfect 1.5" concave in the wood. Cinched it up in my drill press and drilled it down about 1.5" in from every corner, and went down about 3/8" deep. It's allows the balls to move back and forth by about a half inch, and when the top platform is added the CD player simply " floats " on top. just like an original Ginko. This EASILY bested several different cones I have in my collection, a set of Isonodes, a set of Symposium Rollerblocks, and a innertube isolation platform.

Total cost ? $15.

The bass is the tightest and most defined I have ever had in my current system. It made amazing amounts of good things happen under my Lexicon RT-20.

Try it for yourself, it was a winner in my system.
timtim
04-23-09: Undertow
Okay, so here is what I want to know… knuckle rapping cannot be very well proven to tell you anything with a turntable isolation.
Undertow, why not??

first anything physically "Knocking" on something attached to your cartridge will most likely feedback the sound thru your speakers..
not necessarily. if the TT isolation is good any knocking that excites any resonances should get dissipated (if your rack is damped, etc) or decoupled (if you have brass cones, roller-blocks, squash balls, etc) from the TT thereby disallowing it to get to the TT in the 1st place.
(I think the only place where this would not hold is if you knock on the LP itself when the stylus is in the groove).

However are your speakers playing in the room doing it self induced via airborne or not?
The knocking is not creating any significant air pressure changes to modulate the drivers & the speaker terminals are connected to the amp. The amp is on during this test thus the primary input signal feed to the speakers is an electrical feed from the amp output.
so, how are the speaker drivers modulating via airborne if one is knocking on the rack/shelf/plinth, etc??
Sorry, Bomby, didn't mean to misconstrue your words.
--I believe turntable design has truly changed through the years. Yes, it's still a rotational platter, yet, the ways to make it spin are everchanging.
--To all you table rappers out there, stop it. It proves nothing. Plus, I'd hate to have you damage your cartridge.
--To all Gingko owners or diy-ers of balls, your product and method can be fine, but not always, not for every situation and product. There are many ways to isolate--cones, points, balls, tubes, sandboxes, air, wood cubes, etc. Many will do a great job of isolating, and of giving support. Not all will "sound" great in a given situation. You may isolate the hell out of your item, but what if it does something to the sound as well? something not good?
--My opening glib comment was just that, these things have been going on for years--years! But I would never be a buzzkill for someone who's taking the interest to try and improve their system. We all start somewhere. For a lot of us it was the 80's.
--Apologies to Bomby.
--I know it's fun to experiment, but why not just use a wallmount if you're trying to isolate something? If that can't do it then you are in serious need of a solution.
Hey Chashas1,
thanx for the clarification & apologies.
Looks like agree to disagree on TT fundamentals. That's fine with me as we each are entitled to our own opinions.
To all you table rappers out there, stop it. It proves nothing.
I'd like somebody to explain why this is not a good test. Right now those who oppose it are saying "this is not a good test because we say so". I'd like some explanation better than that. I claim that knocking on the rack/shelf/plinth/sandbox, etc excites resonances & one can hear thru one's speakers how well these resonances have been damped before the cartridge picks them up.

Sure every tweak has its sonic signature & that applies to the wall-shelf as well! Your words seem to imply that the wall-shelf has no sonic signature but that's not true. I think that all the tweakers are fully aware that when they undertake a tweak it might not work out & that their effort might be wasted. Goes w/ the territory.

Many times having a wall-shelf is simply not possible for a myriad of reasons - looks too ugly, studs too far away, spouse will not allow it, not enough space, etc, etc. So, the wall-shelf cannot be a panacea for many. Certainly you do not think that these people are sunk???

Looks like we need to part ways on this isolation idea as you certainly subscribe to some other idea(s). That's fine with me.
"I'd like somebody to explain why this is not a good test."
"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."

Problem is Bombay, that you simply don't understand the physics and acoustics involved in translating 'impact-induced' sound transmission with either Structure-Bourne or Air-Bourne Sound transmission and as you say, you don't really care?
Yet you now want us to tell you why your 'rapping' test is irrelevant?
Just go ahead and enjoy yourself....but for heavens sake spare us your attempted pseudo scientific justifications?
Thanks, I am delighted to be forgiven and dismissed all in one paragraph.
I would say, or rather ask, one thing, Bomby, in looking at your system, couldn't most of your problem in needing further isolation be eliminated by removing your source from between your speakers?

p.s. and again, sorry, but you are just plain wrong--a good wall shelf will have less of a sonic signature than the tweeks you have been suggesting. and quit beating on your equipment, you're proving nothing...