cones or amp stand-???

My cheap theory is that the drain theory is not a theory, but marketing assumed to be most palatable for common-sense physicists.

From Stereophile's Bad Vibes!, Shannon Dickson, November, 1995:

"Unfortunately, once we've built or purchased our dream platform, we then have to connect it to a stand or floor and place a component on top. This is the kicker: When you couple the most ideal practical platform to the floor with cones, spikes, or any other rigid footing, even at the ideal locations with respect to each, the best vibration performance you can achieve is nearly 100% transmission of floor-borne vibrations through the platform, without amplifying them or generating any new resonances in floor or platform! The same applies to component-generated vibration. At the very best, the combined structures will roughly approximate the "ideal rigid body" we mentioned earlier, moving through space in synchrony relative to each other so that the motion of the floor is matched by the motion of the shelf, with nothing added.

Any technique that does not provide isolation of external vibrations will only vary the amount of resonant stimulation added to the components concerned. It cannot reduce at all the level of baseline vibrations in the floor or those coupled from the air!

This principle is illustrated by both the "ideal rigid body" line in the compliance curves shown in sidebar 1, and the horizontal unity-gain line (labeled "1.0" in the various transmissibility graphs of sidebar 2). A perfectly rigid structure would not diverge from this unity-gain baseline in either direction, indicating nearly complete transmission of all vibrations between both the floor and the coupled elements.

At first glance, transmitting nearly all of the floor vibrations to a component might seem to be of no benefit at all. On the contrary, this would be a significant accomplishment compared to most real-world coupling schemes, due to an appreciable reduction in random levels of resonance affecting key components, as described above.

Indeed, it is the degree of deviation from this ideal that defines the wide variety of subjective sonic changes experienced by audiophiles using various non-ideal rigid coupling devices, stands, shelves, and components in actual audio systems. Also, when you consider all the ramifications of this scenario, it appropriately undermines the claim by certain purveyors of cones and spikes that these devices have a directional "diode-like effect," forcing discrete vibrations to flow like water from a dam: out of a component, through a coupled shelf, and then into the floor, where they are finally dissipated..."

Read the rest; its good.

Ohlala (aka Pleasure Boy), just skimming thru your first page, I see no mention by the author of air-borne vibrations captured by the components or racking system.

Why do you suppose the author omitted that element?

-IMO

Ohlala et al:

It is simple, just try it in your systems. Who
cares what Shannon Dickson wrote in November, 1995? What mkes him an authority on vibration control? I happen to agree with Stehno.

My previous house had concrete slab on the ground floor. My present listening room is on sprung hardwood floor. I have experimented in both environments.

My guess regarding the first paragraph of the portion of the article I quoted (I assume "skimming" means "reading the first paragraph") is to make his point about the relationship between floor and component as they are attached. Dickinson mentions vibrations via air in the second paragraph and more in the article.

I just read it. It appears the article was written with the express intent of promoting certain products which kept getting mentioned over and over again.

Of course, I could be "biased". :^)

A couple of points I noticed. He is quite right about some things like the need for rigidity and structural integrity of solid type stands. He's also quite right about some of the various damping materials and their limitations.

Where I seem to have difficulty agreeing with him, are the parts where he seems to be convinced that vibrations can be transmitted up from the floor, but cannot be transmitted down from the equipment "like a hose"(as he puts it).

Part of his reasons seem to stem from his description of "cones" as having a good function at the tip, but a poor function at the broad top surface. This is actually one of the main aspects that we(Starsound) address in our product(Audiopoints) design.

The Audiopoints design uses reduction of the Coulomb Friction at the top surfaces of the "cone" to improve the ability of these vibrations to move continuously(in real time)from the component through the Audiopoint. A high coefficient of Coulomb Friction at the top of the "cone" will cause delays and inefficiencies in this vibration transmission, reducing effectiveness. By lowering Coulumb Friction(using proper materials and mechanical grounding) this allows a real-time continuous transmission of vibrations without the buildup or reflection of the vibrations back into the component. Additionally, the use of rubbery materials or air bladders just aggravates the problem instead of curing it, by creating more resistance(Coulomb Friction) in the juncture, and thus causing the equipment to behave as a "resonance capacitor" or resonance storage device, storing and returning the vibrations back to the equipment instead of effectively dealing with the airborne resonance problems.

For another bit of interesting reading, complete with mathematic scientific calculations and proofs about how reducing Coulomb Friction can improve vibration management in the audio environment, please refer to the Coulomb Friction White Paper on our website, written by a Mechanical Engineeer.
http://audiopoints.com/coulomb.html

As you can see, there is more than one side to this story, and much has transpired since that Stereophile article has been written. Perhaps the author himself may even have some different opinions today.

Tom Lyons
Starsound Technologies