Getting granite tomorrow.

Making an isolation platform for my Acoustic Signiture TT. It is 18x24. I have this materials. Granite slab 1 1/4 thick. 2 MDF boards 3/4 thick each, Cork one inch and 2 rubber truck liners 3/4 inch thick and 8 wooden buttons for support. I was going to put MDF boards on bottom then rubber then cork and last granite on top. Is this the best order? Or should I make 2 sandwiches out of materials? Also If I dont use spike cups for TT will I crack the granite or damage the spikes? I though it may make a better isolation or do you think it would matter. Any opinions appreciated
I have 3 Diamond racing cones. Would they be enough to support 200 lbs?
The lack of responses may be due to your confusion of basic concepts. You said you're trying achieve "isolation" yet you've assembled a pile of mostly non-compliant materials that will provide little isolation to speak of. Either the goal or the materials must change. Which is it to be? We're so easily confused by randomness. ;)

Granite, mdf, wood buttons, spikes and spike cups are essentially non-compliant. Non-compliant materials and devices provide COUPLING, which is the precise opposite of ISOLATION.

Your massier items (granite, mdf, the TT itself) can contribute to isolation but ONLY if used to optimally mass-load some other compliant material or device (like springs, an air bladder or sorbothane).

Those rubber truck liners are probably compliant and might provide some isolation, but only if optimally mass-loaded. How thick is the rubber? What are its compression and rebound characteristics under various loads? With that information a mechanical engineer could estimate the optimal mass loading for greatest isolation at various frequencies. Without that information you're reduced to trial and error. You may end up with a Ford Focus on industrial-grade truck shocks (BOING!!!), or a 3/4 ton pickup on Ford Focus shocks (BONK!!!) or... you might get it just right. :)

What are you trying to isolate the TT from anyway? Forget the random pile of stuff. Identify your problems and goals and appropriate solutions will present themselves.
Three BDR cones would probably support 2,000 lbs., but for basic technical questions the manufacturer's website or help line is usually a reliable source.

Hi BlueRanger,

Here's the thing: Isolate. (Just as Doug suggests)

I love DIY projects, but there are times that proprietary products are very difficult to surpass.

You don't have to go through a lot of trial and error. You don't even have to learn manufacturer's specs. The Vibraplane that I bought works tremendously well.

My audio buddy around the corner has one, and has gone to the extra lengths to mass load the VP with a 1" thick steel plate. The difference between loaded and unloaded was very substantial. In my estimation it was worth the trouble, and I have to help him every time he moves his TT, the steel plate and VP, so it must be worth some Serious Sonic Benefit.

When time and finances allow, I will buy a steel plate to mass load my VP-TT. You may need to evaluate what supports this combination, because the VP is 150 lbs, the ballast is 140 lbs or so, and then there's the TT's weight to consider. My stack weighs over 500 lbs. Make sure your rack and floors can handle it.

If you want to see what the results are like, without spending $2500, buy a piece of slate (granite rings) 2" thick and two bicycle tires. Half inflate the tires and place them under the slate. Level the TT, level your arm, level your headshell and listen to some of the most wonderful improvement you may ever hear in your system.

In future, consider contacting the Forum BEFORE you begin collecting materials for a project. It could save you time and pain in the wallet.

Keep us posted. You're headed in the right direction: Isolation is a beautiful thing. It would be great to hear what you learn as you progress.

I have no relationship with Vibraplane, nor with Sound of Silence (Steve Klein's business that sells VPs). Steve has been a very gracious host and helped with my VP, even though I owned it before meeting him.

The idea for slate and bicycle tubes came from an isolation sales rep who took pity on a penny-pinching audiophile. When in grad school his class tested all the isolation devices then available. He said 95% of the results could be had with the setup suggested above. Either way, you win. Go to it!

Very Best of Luck to You,

Here's our poor man's isolation setup. Of course it helps that I have a PhD materials scientist at home to dummy-check my stupider ideas. This explanation may help demonstrate how breaking a complex project into its discrete elements helps inform workable decisions.

Step 1. Our rack and components weigh ~450lbs. The first job was to provide this whole pile some isolation from our somewhat excitable wood floor. That was easy and cost <$50. All I did was buy sorbothane pucks in the appropriate size, durometer and quantity needed to isolate 450 pounds. This was simple to calculate with the information on the manufacturer's website, or on McMaster-Carr's site. One puck beneath each of my rack's eight feet plus two more beneath the heavy end of the rack and voila! I won't claim it matches a Minus-K, but I can jump up and down next to the TT and it never skips.

Step 2. was to isolate each individual shelf within the rack. That was also cheap and easy because I followed the same strategy: small, sorbothane hemispheres or Vibrapods beneath each shelf, of a size, durometer and quantity suitable for the weight being supported. I won't claim this equals a Vibraplane, but it did improve the sound and cost peanuts.

Step 3. was to isolate each individual component from the shelf it sits on, and this is where the DIY/cheapskate model broke down. After trying several things we settled on Symposium Rollerblocks + tungsten bearings, cryoed. Four sets were not cheap, even bought used, but the improvements beneath any component with a large transformer, power supply or tubes were remarkable.

Step 3(a) was the TT, a special case. Any compliance directly beneath a TT has both positive and negative effects. It's a tradeoff between lowering the noise floor (due to better isolation) and dulling dynamics and bass response (due to unwanted TT movement). After trying spikes (no isolation, great dynamics) and compliant materials (good isolation, sleepy dynamics) we settled on Stillpoints with Risers and Inverted Risers. These provide a nice improvement in the sound floor with only a minor loss in dynamics and bass. A reasonable compromise.

Note, the Stillpoints were nowhere near as effective as the Rollerblocks beneath our amps, power supplies, etc. Similarly, Rollerblocks beneath the TT were a disaster. Different applications require different solutions. Further, everyone's TT and sonic priorities differ so YMMV definitely applies.

And then there's speakers... :)
So Doug, what are you using under the speakers? Since I moved a couple of years ago from a nice concrete floor to a suspended wooden floor (albeit decently solid), I've come to realize (despite my best efforts) that some type of decoupling is going to be needed at the speaker/floor interface since too much mid bass energy is being directed into the substructure. And, it probably isn't going to be cheap. I've tried the Herbie devices and they were abysmal in my application. The next step is something like Stillpoint Ultras or the Track Audio decoupling spikes, but now we're talking quite a bit of cash for eight feet. I'd be curious as to your approach. Cheers.
Doug, that is a very nice explanation of the various steps and results. I had a different experience with my unsuspended turntable. I did put a Vibraplane pre-loaded with 136 lbs of steel plate ballast under my unsuspended turntable. Interestingly, I found that the noise floor was lowered AND dynamics and bass response improved.

It just goes to show, as you wrote, that everyone's TT is different and thus solutions may work in some situations and not in others. I will shortly be trying out a suspended TT on the Vibraplane, and I may find the added isolation is not needed and perhaps even detrimental to the sonics.
Granite Rings....not a good idea
That's really interesting that a Vibraplane beneath your TT improved both noise floor and dynamics. I don't know how they function but I've heard good things from many people. We haven't gotten around to trying one ourselves... so many vibrations, so little time!

We've had the shaky floor thing going from when we first got speakers big enough to go below 40Hz. I once tried isolating the floor from them by placing the speakers on butcher block boards, with the boards just sitting on the carpet. When Paul saw this setup he asked what I was doing.

"The speakers excite vibrations in the floor and that's undoubtedly getting to the components in the rack. I thought I'd try isolating them from the floor."

He gave me the pained look scientists reserve for children and idiots (I've seen it before, and since).

Well, we were both right. The isolation worked and the floor got quieter, woo-hoo. However, Paul's scepticism was justified because it sounded like crap.

Think about it. Isolating/decoupling requires allowing a component to move, and let's recall Newton's laws of motion. If a speaker cabinet is free to move then some portion of the energy from each cone excursion, which ought to be 100% dedicated to displacing air forward, will instead displace the cabinet backward. Result? Slurred transients, reduced dynamics, dopplered waveforms and general sonic muck. Decoupling is disastrous for speakers.

Stillpoints do decouple so I'd expect them to be a net negative beneath speakers. OTOH, those Track Audio speaker spikes look similar to the (very effective) Audiopoints spikes we now use. But it's an error to say they de-couple. Spikes couple, that is their purpose. A solid coupling improves speaker performance but as a side-effect the floor will shake more, not less. That problem must be addressed elsewhere, not at the speakers.

Spike, bolt or glue your speakers to the floor as rigidly as possible. Perfect rigidity, if we could achieve it, would result in 100% of each cone excursion moving air and 0% moving the speaker cabinet. That's the goal.

If a floor's excitable then two approaches suggest themselves:
1. reinforce the floor to resist/dampen/absorb energies
2. isolate sensitive gear from the floor
Here's my added thoughts in relation to speakers and suspended wood floors;

I have a suspended wood floor "joist below are resilent" , two layers of 3/4 inch ply on top. First sheet is tongue and groove with glue applied on the top portion of the joist and t/g and then screwed. Second layer, 3/4 inch stangered offer the first sheets joints. Glue spead using a notch trowel of entire area and then sheet installed. Screwed threw to the joist and everywhere else screwed every 6 to 8 inches. Finished with underpad and carpet.

With speakers in place "MBL 101E's" the floor still interacts "this sucks big time" floor interacting as a trampoline and for sure effecting in a negative way the sonics.

I have tried so many variations of this and that and never been really fully satisfied but always learning along the way.

My latest invention; 4 Large Herbie pucks with Titanium incerts, then placed a 3/8 inch ball bearing on each and then ontop of that a Symposium Plus Svelt platform. The carpet and underpad it pretty plush so the Herbie puck and ball bearing have pretty well sunk in leaving the Svelt platform bottom pretty well level with the carpet.

My speaker is placed upon with no spikes, very interesting indeed in a positive way. Next will be to use Rollerblocks instead of the Herbie puck and ball bearing but for now sounding very nice and with very minimal floor interaction.

Stand is iso;ated along with each pce of gear, my table is placed upon a Minus K. I have my motor with is also but will be changing that and only have the table it's self and compare.

It's all very interesting indeed, what I have learned is vibrations interacting are evil in a negative way.
Agree with Doug about speakers. I put one expandable column directly under each speaker in the basement below my listening room. I bought these at Home Depot for about $30 each. My speakers aren't spiked because I have very soft, very old wide pine floor boards in my listening room. The speakers are, however, on hard round cones and as each speaker weights 200 lbs, they don't move. As Doug says, one wants all of the speaker's energy directed at the forward/backward movement of the cone drivers. The cabinet should not move at all.

I also placed two columns under my equipment rack to support it's massive weight, but also to reduce the floor bounce. I've found the solution to be quite effective.

I'm in the process of building a new rack. I considered two distinct approaches. One is to have massive shelves to which the components are coupled, but the shelves need to be isolated from the rack structure and from floor born vibrations. The other approach is to have a very rigid, heavy rack coupled to a solid floor but have the components isolated from the shelves. I've chosen the latter approach and have the components on a Vibraplane and Townshend Seismic sinks for isolation all on a very rigid and massive rack/frame system. I guess I'll find out if it is effective once I finish building it.
Thanks for the responses all. Doug, indeed my experiments have proved that anything that allows the speaker to move in any plane results in exactly what you and Paul are hearing. Thus far, I've found that rigid spikes allow for the best sound in my application. The Track Audio spikes intrigue me as they are offered in both a coupling and decoupling version; from my reading it seems the decoupling version can be adjusted for various mass loads, and that the degree of compliance is minimal - still as you rightly point out, anything that allows the cabinet as opposed to the air to move is theoretically detrimental. Alas, support from beneath isn't an option since the room is over the garage. Perhaps I should be focusing on better coupling between the speaker cabinet, the spike and the floor. Back to the drawing board.
Adding to my info. above I believe it will depend on the design of your actual speaker for end results, not all being equal.
I set up my TT stand in way descibed by Audiogalore and it works for me. 24X18 X 1 1/4 granite, 1 inch of cork, 1 1/2 inch rubber, 2 pieces 3/4 thick of MDF with sorbethane pucks. Bass deep and tight. No glare from highs. Also of note I turned up the gain from 42 to 52 on phono preamp and ran Adcom preamp in passive. That was a big difference too on the Shure 97xe. Having an SAS stylist come in next week. The Benz L2 was no slouch and conveyed more musical detail but the Shure tracks better and is a very very musical cartridge. The Benz was humming more and more and finally I had enough. Couldnt afford to get a 1K cartridge so I got the Shure for the time being. Some other members wrote they had negative experiences with granite. Maybe it just didnt blend in with their systems or maybe they didnt use enough dampening. Mike
It is only recently that I have experienced good isolation from vibration. I have spent at least 25 years exploring isolation devices, using bladders, spikes, mass, wood, cork, springs, like pole magnets, multiple layer shelves, carbon, and even active phase reversing electronics. I have sought to directly couple speakers with spikes all the way to decoupling them with gel. Everything had some benefits and some liabilities. Most could be heard to make a difference. None of these continued to impress me for very long.

The one device that has continued to impress me is the StillPoints new Ultra Stainless Steels and Ultra Five isolation feet, not the old cone devices. Basically these devices change vertical motion into horizontal motion and heat. The key thing is that you don't have to be concerned with where you want to take it. I no longer have concern with footfalls when playing vinyl and have great clarity and realistic sound stage.
Had problems with my suspended floor in the living room where music listening is done (wood with joists over a basement with carpet over the wood sub-floor). The bass excited the turntable, tonearm, and cartridge. The components are in a good rack with Stillpoints and other such isolation aids under all components. After many false starts with various "fixes", what worked is to allow my speakers' feet (not spikes) to sit on thick ceramic floor tiles with Vibrapods beneath the tiles. I had originally spiked the speakers to the sub-floor both over where the joists are and in between,neither worked. Getting rid of the spikes was key.
A few years ago, I hired a water-jet company to cut some slate slabs for me in order to make turntable plinths (for my own use, only). During one of my visits, I noted that they had stacks of very dense yet very light styrofoam-like slabs lying around, some about 3 inches thick and some about 5 inches thick. I use the term "styrofoam-like", because this stuff is much tougher than styrofoam and does not flake or fall apart, unlike the styrofoam we are used to. In fact, I use a handsaw to cut it. It's also black instead of white. They informed me that the stuff was packing material for heavy but fragile items that were sent to them for processing. They also invited me to take as much as I want. I am using it as an element of a vibration-absorbing structure under my SP10 Mk3. I would not claim that the net effect of my construct is superior to a Vibraplane or MinusK platform, but it works impressively well. (The Mk3 sits on 3 Stillpoints which ride on half-inch thick lucite plates that in turn sit atop the mystery packing material, which sits on a granite shelf dampened by a hardwood backing [an Adona shelf]. All of that sits on an Adona rack.) To give you an idea of the structural integrity of the packing material, it does not crush or bend in any way under the ~100-lb weight of the Mk3 in its slate and wood plinth. Yet each piece is "light as a feather", a favorable property; it would tend to dissipate energy, rather than storing it.
I realize now I should not use the term "dense" to describe the material mentioned above, since that suggests high weight per unit volume. In fact, it is very light in weight per unit volume.