Another stalker joins the party. Make that two stalkers. Shadorne has a little difficulty with reading comprehension or so it would appear. Of course he might be pretending to be slow, it's difficult to say for sure.
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From the Sorbothane Wikipedia page,
"Sorbothane exhibits many of the properties of rubber, silicone, and other elastic polymers. It is considered to be a good vibration damping material, an acoustic insulator, and highly durable. An unusually high amount of the energy from an object dropped onto Sorbothane is absorbed. The feel and damping qualities of Sorbothane have been likened to those of meat."
The last sentence caught my eye. Has anyone thought about using meat under components or speakers? One suspects Spam might be the cost benefit champion. Span in a can already has a constrained layer constrained - the can. But there probably isn’t a real substitute for Filet Mignon. Why use a synthetic when you can use the real McCoy? It’s in the meat! |
No one is suggesting there has to be a choice between high mass and low mass designs. Those are just design concepts. There are obviously a lot of variables and parameters involved. Mass is only one of them. You got your spring and unstrung designs. Belt drive vs direct drive. Tangential vs radial tracking. Vacuum hold down. What have you. And there are a great many successful turntables including magnetic levitation and air bearing everything that tend to actually eliminate the whole variable of MASS. The best way to solve for a set of simultaneous equations in many unknowns is start eliminating the unknowns. Obviously also, not matter what design concept is employed in a turntable the performance of that turntable can be easily and reliably improved by vibration isolation. I don't think any list of great turntables would be complete with Linn, Walker, Maplenoll, Verdier, AC Raven, Caliburn Continuum, VPI, SOTA, Basis, and a bunch more I probably forgot. |
Viscoelastic materials like Sorbothane convert vibration to heat ONLY if they are constrained. That’s why they call it contained layer damping. Sometimes there is a thin layer of aluminum On top of the viscoelastic material that constrains it. The vibration in the one direction, e.g., vertical direction, produces shear forces in the orthogonal (e.g., horizontal) direction in the soft constrained layer. So it would not actually make sense to attach Sorbothane to anything without constraining it, since the shear forces are due to the fact that the Sorbothane is being constrained. It does make some sense that Sorbothane used as footers (or as insoles of running shoes) since the component or speaker or person’s mass will act as the constraining mechanism. I gave up on Sorbothane myself a long time ago. As I opined recently there are much better materials to use as the constrained layer. But more power to anyone who gets good results with it.
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Go stalk someone else, Pumpy.
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Shadow, grow up and find someone else to stalk. There are no high end low mass turntables made of plastic. That would be pretty stupid. Just admit you were wrong and move along. |
Pretty sure the analogy doesn't extend to Sumo wrestlers.
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That’s a really interesting point since isolating an object on a mass-spring system actually reduces the mass of the object by a significant amount. Kind of your own private anti gravity machine. Also, one would have to analyze air bearing/high mass platter turntable like Verdier and Maplenoll and Walker to figure out just how they fit into the whole high mass vs low mass spectrum. I had an air bearing everything Maplenoll with special 50 lb platter isolated on a special version of a Nimbus sub Hertz platform. That turntable set up did NOT suffer slowness or any other malady one might ascribe to high mass turntables. |
audiotroy wrote,
"Many years ago we compared a heavy Basis table with an acrylic and brass damped plater, with a heavy acrylic bass and an oil damped suspension to a Roksan which was considerably lighter with a lightweight wooden plinth and frame, the entire table was much lighter in weight and the Basis sounded slow, dead, and dreadfully out of tune compared to the Roksan."
While that's interesting it doesn't actually win the argument of high mass vs low mass turntables because there are any number of other reasons you got the results you did. Mass is only one variable. One should not jump to conclusions based on one test.
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Uh, nobody's talking about plastic turntables. What a load of hooey. I bet you had a plastic turntable when you were wearing bellbottoms. |
rotarius
Well, I have to correct "The Audio Doctor" because I am an engineer and it pains me to read some of the stuff on audio forums. First of all, it should not be about different philosophies, it should be about scientific fact. Saying that something more massive will store more energy and release it more slowly compared to something lighter is just plain WRONG.
its not so simple but it pains me to say I think the statement is actually CORRECT. There are other factors to consider, however, such as inertia and stiffness. Not to mention rotational moments which would obviously be much higher for heavy platters. |
Huh? What? I never said Sorbothane only sounds good contstrained. What I said was Sorbothane always sounds bad, no matter what. If you can find any place where Sorbothane sounds good you are a genius and I congratulate you. Trust me, there are much better sounding though similar looking materials when constructing constrained layer dampers.
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