Wood blocks underneath components?? snake oil?

Cdc, FWIW my question is probably not relevant as I was mixing apples and oranges so to speak, i.e. vibrations control vs resonance control, but FWIW yes ceramics do have a resonance point.

Best example I can think of which graphically show this is the old Memorex commencial showing the glass (similar to ceramics) being shattered by a singers voice (with out regard to whether or not it was actually Ella's voice that did it). It isn't so much as whether or not ceramics have a resonance point, it is what will the substance do when it's resonance point is reached. Depending on the amplitude of the sound at the resonance point of the glass it will ring, ring excessively, then shatter if the signal is strong enuf. If the resonance frequency is high enuf you won't hear the ringing - you will just see the shattering. (But your dog will be hiding in the bath tub!)

As a pratical matter in audio usually all that will happen is that at the resonance point there will be a peak in frequency at the point of the resonance, which you may or may not hear depending on its amplitude. Think of wood speaker cabinet resonances and how, or whether they are damped by the manufacturer and how their existence affects the sound. Also as excessive high frequencies can cause glass to ring I would imaging that would be one of the contributors to the level of microphonics we hear in tubes, thus the application of damping rings to damp the vibrations. Thus the purpose of damping rings applied to tubes. Just a guess of course.

What I was trying to figure out in my question was do we factor into our consideration of vibration control (products & application) the resonance points of the products themselves and how this might interact with the resonance points of the products we are trying to control, or are we simply dealing with either a broad based vibration damper (such as a soft rubber type product) or narrow based product used to facilitate the transmission of a narrow band of frequencies, such as metal or glass (ceramics).

I wonder if a lot of the differences that folks attach to the different vibration control products have any relationship to their ability to control (damp) the resonance points of the audio equipment that they are using.

I've asked this question before and have never gotten a response. Perhaps I'm just whacked out on this and there is no basis for a question, let alone an intelligent answer.

I use hockey pucks and they work just fine.

09-03-06: Mitch4t
I use hockey pucks and they work just fine.

Cryo'd?

:)

Tvad, I purchased a box of the pucks from a supplier in Minnesota. They were stored in an un-insulated warehouse inside a cardboard box. I can a assume with the extreme winters in Minnesota, that they were probably exposed to some temperatures below freezing. Given that, they were probably unintentionally partially cryo'd.

883dave, I am going to try and explain what an isolator really is and what it does refering to my textbook and some catalogs I use at work. Firstly, I did skim through the stereophile article mentioned above and it is somewhat confusing since it mentions the best you can do is 100% transmission and then the last few pages are about proper isolation/damping. Their conclusion then was getting a rigid, sturdy rack and then isolating the source components individually so even if I didn't know better, I wouldn't just put cones under everything. Can you imagine being rigidly coupled to the wheels of your car without springs and shocks? I cannot comment on the stuff about effect of vibration on passive components and phase shifts and such.
To put it simply, every material has a natural frequency at which it will vibrate when subjected to a disturbing force. Natural frequency of a system depends on several variables including stiffness of the material used, mass, shape etc. In general, lesser the stiffness, lower is the natural frequency.
Vibration is a force and establishing an opposing force can effectively reduce it's transmission. This is the function of an isolator. Simply put it is a spring. It can be a steel spring, air spring or an elastomeric spring. A damper is a device by which vibrational energy can be dissipated, typically by converting it to heat. A steel spring is only an isolator whereas an elastomer can be an isolator and a damper. An isolator must deflect under load to oppose vibration. NO PROTECTION WITHOUT DEFLECTION! The fundamental property of an isolator is it must be resilient, ie, it should be able to return t it's original state without load.
An isolator is defined by 2 properties, it's own natural frequency and how much it can deflect (in our case compress) under the maximum allowable load which is dictated by the material and structure and is called static deflection. In general, the greater the difference between it's natural frequency and the disturbing frequency, the better the efficiency of isolation. The greater the static deflection, the more effective the isolation. Deflection however should be limited to the direction of travel of the force, usually vertical thru the isolator. An isolator must be constrained to limit horizontal movement although there are devices that isolate in shear also.
Pneumatic springs have the lowest natural frequency, can be as low as 2Hz and are excellent for audio purposes. However by using only an inner tube or soft feet you get plenty of sway. If you look at typical isolators in Lord, Mcmaster etc, the elstomers are bonded to some steel to add rigidity to prevent this. They are inexpensive and can be mounted between a shelf and a platform for the source. I don't know what a vibraplane mentioned in the review is but I am sure it is a platform with constrained air springs. Bright star may has one also I think. Usually precision lab equipment is isolated using some type of spring. As the article says, "draining vibration" with fancy hard substances underneath your component is all bunk, sorry.