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Any notion that EAR does not make C-1002 (the good stuff) equipment feet is false and even if it were true all one has to do is cut a few squares of sheet to make feet.
There are also groumets that could be used as feet.
And feet that could be used as feet.
A Foolish Inconsistency Is The Hobgoblin Of Little Minds- Alfred E. Neuman
Edits: 10/23/20 10/23/20 10/23/20 10/23/20Follow Ups:
Since you are referring to an issue within another thread, my response is that by arbitrarily or subjectively stacking layers of the E·A·R vibration damping material, or by using 35 cent E·A·R mounting feet does not necessarily mean it will naturally *sound better* than another vibration damping material design, no matter what is indicated by one or more aspects of the material specifications and measurements. Perhaps you will consider a comparative evaluation of the E·A·R MF-1010 Blue Mounting Feet vs. the adhesive-backed AcoustiFeet silicone feet I recommended and post an honest report in the forum. I don't have a dog in the hunt other than previously suggesting a product I have direct experience of for a fellow AA Inmate.
I have found that the 75 Cent black C-1002 feet are excellent for low signal level components. They improved the detail retrieval and sense of treble air under my pre-amp and phono stage.
They were not useful under any main amplifiers, muddying the signal somewhat. I continue to use unfinished Gabon Ebony feet under my amplifiers.
As an aside, EAR SD-40 is under all my transformers and chokes; the best sounding arm board for my VPI HW-19 was a sandwich of SD-40 between an aluminum and a wood veneer sheet.
Emoji's: a visual aid for those who need to be drawn a picture
Thanks for sharing your experience of the material, B. Scarpia. It's always of great value to know of specific applications where the effect of any device is satisfactory or not, based on direct experience. I concur that highly compliant decoupling pads/footers tend to sound better when positioned under source components rather than under an amplifier/preamplifier, where I prefer a three layer DIY footer with a much less compliant pad, adhered to a carbon fiber disc, with a conical coupling element for vibration control. If I hear little or no difference between lifting a preamplifier into the air vs. resting the enclosure on a set of footers, it tends to sound nominally transparent, to my ear.
To All:
I spent a 33 year R&D career at EAR in the field of acoustics and vibration.
And I am very familiar with C1002 isolation feet. One of the best features of the Isodamp isolating feet is that they are highly damped - that is, they have little amplification of vibration energy at the system resonance (which depends on various factors like stiffness and mass). There are MANY other isolation materials that have amplification problems at resonance, though some of them may have a higher attenuation rate above resonance. There are quite a few isolation devices for audio on the market - some of them VERY expensive. The "Gold Standard" for the actual isolation performance of any isolator is a "transmissibility curve" with a real world load equal to the audio component. This will show the areas of amplification (at resonance), and the actual isolation attenuation. I note that very few (if any) audio isolator manufactures publish actual transmissibility curves. And, there is a chance that the particular isolation characteristics of an audio isolator may, or may not, be to the liking of a listener, depending on how they change the sound of a component. So there is likely no BEST audio isolator that beats everything else - sonic preferences get into the mix. All this said, the C1002 isolator is a device with good technical performance, and does not cost an arm and a leg.
We have discussed your career at E·A·R before, and I enjoyed our conversation, fastcat. I see there are various C1002 isolation feet of the same 3.12mm x 13.23mm size. Does each product offer different properties? They are quite small, so are they more appropriate for specific applications, perhaps not audio related in nature? If there's anyone who could advise folks how to implement the material for a custom DIY footer build, it must be you, fastcat.
Cheers, Duster
Duster:
For larger components there is an EAR isolation footer that is 1.5" diameter by 0.75" height that will handle 10-20 pounds. Parts Connexion and Michael Percy have them.
It would be interesting to do a large scale survey of high end audio isolators with the lab equipment that I had when I was still working. Such technical testing would easily reveal which units were performing best as a vibration isolator. I have uploaded an image showing some transmissibility curves for some grommets, including the C-1002 type.
Despite what ever a technical test might reveal about the true performance of an audio isolator, it would be true that the sonic effect of any given isolator could be different. So in the end it could come down to the particular sonic character that a listener likes, as much or more so than the technical performance of the isolator. As always, high end audio is complex, and not easily distilled to simple, easy answers.
I use MF-1010 (C-1002) feet and have been happy with four of them on equipment up to around 25lbs. I've looked at the MF-1010 in other materials: V-2325, V-2590, and V-2775. The C-1002 has the lowest transmissibility of these. On the Versadamp spec sheet there is a graph of transmissibility relative to frequency. Before getting to "try it and see," would you think that audio electronics would benefit from targeting a specific frequency range for the material's peak transmissibility, as well as where it's lowest?
It looks like Partsconnexion has raised the price of their MF-1010 feet. Since I'm interested in listening test results, I'd be willing to mail someone four MF-1010 C-1002 feet if they want to do some comparisons. (CONUS only, I've got black or blue.)
Willsw:
In the transmissibility graph, the peak is at a lower frequency range. To some extent, where the peak frequency is at will depend on the mass that is being isolated. Typically, the higher the mass, the lower the peak frequency point. And, the magnitude of the peak frequency is also usually higher in level with increasing mass. The peak frequency range of an isolator response is an area where input vibration is AMPLIFIED (not attenuated). So the inherent damping of the C-1002 material helps to limit the amplitude of the peak frequency MORE than most isolation materials (those that do not have inherent damping). This is a desirable characteristic, because amplified vibration energy is not good. In the graph you will notice that the response drops off above the peak resonant point. The drop off area is where vibration isolation occurs, and this is what you are after in using an isolator. In an IDEAL world, a perfect isolator would have NO peak frequency - just high attenuation of the input vibration across a very wide frequency range (below 20Hz to 20 KHz).
Regarding audio electronics, having the peak frequency as low as possible (and the peak amplitude as low as possible)would be very desirable - and perhaps well below 20 Hz (not always practical or achievable, as there are always trade offs). Because every piece of audio electronics have different masses, stiffness, and internal mechanical conditions, it is hard to predict just what effect a given isolator would have (unless you were doing extensive lab work ($$$$). In general, a good isolator should generally reduce the vibration of internal electronic components, which will bring you closer to the sound that the component could produce if it were not affected by external vibration. Usually a step forward, but depending on listener sonic tastes, you may or may not like the results. There are no simple universal answers - try some good isolators and see what happens. All this is complex because of so many component variables, and so many different listener tastes in what they see as "correct" sonics.
Thank you for the reply. I phrased my question oddly given the application. I meant to ask about positioning the peak in order to avoid it. I was thinking about the difference between the hardest and softest of those three Versadamp materials. One (V-2350) peaks around 60Hz but is excellent above 75Hz, and is also a sharper peak. The other (V-2725) has a softer peak around 150Hz, but below 60Hz it has better performance than any of the others. I would guess that external vibrations would be more likely to be at these low frequencies.
Time to listen, then.
I find the notion of vibration isolation for audio purposes often tends to be too aggressive, in that the environments of industrial equipment tends to be rather severe if assertive vibration isolation is required. On the other hand, footfalls affecting a turntable, airborne and structural vibrations/resonances caused by bass drivers, and the transport mechanism of a CD player are the only matters that tend to be addressed by vibration isolation devices for audio purposes.
Just how severe are these issues within a typical audio system and listening room to need industrial or laboratory grade isolation? When a compliant material is implemented for the purpose of decoupling a device from the surface it is positioned upon, there is often a sonic downside due to stored energy which tends to be audible. I find that a vibration isolation footer with too much compliant decoupling as the only element involved tends to sound colored, rather than a design that also involves rigid coupling and/or vibration blocking/dissipating aspects within a DIY vibration control footer design.
Implementing a minimal compliant decoupling aspect along with a rigid vibration/resonance blocking/dissipating aspect is my favorite DIY method, with the addition of a conical coupling aspect for specific applications providing another level of resonance control. What I'm speaking of is the audiophile notion of custom tuning which attempts to shift the resonances of an audio component to an area that simply sounds better rather than trying to either use severe damping methods to obliterate vibration/resonance in a heavy-handed overdamped manner, which tends to suck the life out the presentation of an audio system.
A lively sound with minimal coloration is always the goal when positioning any vibration control device under a component within my various audio set-ups. I'm looking forward to implementing a set of MF-1010 C-1002 feet kindly provided by willsw as the compliant decoupling aspect of a set of DIY vibration control footers, featuring laminated carbon fiber composite discs as a rigid vibration/resonance blocking/dissipating base to mount the MF-1010 C-1002 feet upon. Either as a freestanding footer design or adhered to the bottom of an audio component, is yet to be determined.
willsw,I tried one of the other EAR products in the 1000 series that was harder and stiffer and I preferred the softer C-1002.
A Foolish Inconsistency Is The Hobgoblin Of Little Minds- Alfred E. Neuman
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