Jitter, I just explained it. I don’t like having to repeat myself so I won’t. By the way if you’re trying to convince me that you’re a little thick you’re doing an excellent job. Dylan used to answer when asked what if someone rushed the stage, just kick him in the head. He'll get the idea. You, on the other hand, keep coming backing for more. I don't mind if you don't. 😬
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I’m glad you mentioned that, Todd, as one of the really big advantages of my "new style" cryo’d springs is their size, being only about 3/4" compressed in height. So they will Fit just about anywhere. You could even use them on submarines, one supposes, where space is a supreme issue. Hel-loo, US Navy! Are you listening? The other advantage of my mini springs that may not be obvious is that their lateral stability is greater than for larger springs, due to lower center of gravity when under load. Thus, they can be placed directly under components without all the trouble and expense and SPACE of having to place boards underneath the components as in the old days. My Promethean Base, for example, sorry no longer available, employed springs that were about 2 1/2" compressed height.
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Tom, while I can appreciate your persistence in this matter, apparently there CAN be isolation where there is MOTION as demonstrated by LIGO, the 4 km long interferometer experiment to detect gravity waves - the most critical portion of which is the vibration ISOLATION system - which BTW was successful last year in detecting gravity waves, you know, those teeny tiny physical waves left over from the Big Bang with amplitudes the size of atomic particles. HEL-LOO! So, apparently there CAN be ISOLATION where there is MOTION. I also submit as evidence all the testimony from users of vibration isolation devices on this thread. Have you NOT been paying attention? |
One point, the shallowness of the bottom cup doesn’t affect frequency of isolation as Barry theorizes. It affects effectiveness of isolation. Roller bearings aren’t really analogous to mass on spring devices. I.e, a very shallow concave surface provides better lateral isolation (ease of motion) but worse rotational isolation, since the component cannot rotate much when forced by rotational forces, it rotates by climbing the walls of the concave surface. Thus the shallowness is a trade off, it can't be too shallow or too concave. You could probably get really good horizontal isolation with flat bottoms and flat tops, you would just have to constrain the bearings from moving too much, and the component would have to be perfectly level and balanced. It could be done. So you got your roller bearings for the horizontal plane and 3 rotational directions and you got your springs for the vertical. Then all you have to worry about is how you mount the whole contraption on the floor and how to mount the thing on springs. Ah, the art of isolation.
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Actually the high carbon chrome steel bearings require the extremely hard surface of the top thingies that are provided to perform properly. The underneath surface of the component doesn’t quite cut it, it’s not hard enough and tends to flex. The other problem is without the two upper pieces the component will tend to roll. All three bearings need their top constraining pieces. This constraint forces the bearings to move very slightly up the concave inside of the bottom cup when forced by external uh, forces. All three bearings must be free to move freely in their bottom cups. Otherwise you lose all the isolation. The component must obviously be leveled precisely on the roller bearings and the roller bearing just be in located precisely such that mass is uniformly distributed.
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toddverrone
Not a bad idea, Geoff! Except it will make me want some better made, metal roller bearings and cups.. then I'd have to spend 💰.
Ah, the timeless audiophile predicament. 😀😀
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I second the roller bearing idea. The concave shape of the base is a very shallow angle so there is some isolation horizontally I think. They also are good in the twist and the other two rotational directions due to the concave shape of the roller bearing bases. Can’t recall if I mentioned it already but Super Balls on Snaple bottle caps is a faux roller bearings for those DIYers out there.
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georgehifi
+1 wolf, he knows that, but chooses to ignore it.
George, I would give you the same advice I gave Wolfie but alas, I fear, you know, judging by your own words, you don’t have a school you can march yourself down to and ask for your money back.
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Wolfie, can I suggest you march yourself right down to that audio engineering school you went to, assuming you did go to one, and demand your money back? On a related subject have you given any consideration to some sort of reading comprehension refresher course. |
George, the part of the AC that goes in the direction of the speakers is obviously the only part that matters. Who cares about the part that travels in the direction toward the power company? That’s why fuses in AC circuits are directional. You don’t have a leg to stand on. You can try holding your breath until you turn blue, mox nix to me.
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Ouch! George you really know how to hurt a guy. Does this mean you don't wish to argue till you're blue in the face as usual?
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Geoffkait: "nothing can provide 100% isolation at 5Hz"
Georgehifi: "Did I say total Isolation, NO!"
Geoffkait: "So, what did you mean to say, 1% isolation? 10% isolation? That’s why it was misleading when you stated isolation down to 5 Hz. Capish?"
Georgehifi: "And neither can anything else, there is airborne feed back from speakers that also comes into it short of putting the equipment in another room this is the hardest one to eliminate, also if you have tubes that are micro-phonic, then your up a creek without a paddle."
Geoffkait: "Uh, one said anything else can provide 100% isolation at 5 Hz. Everybody knows almost all REAL isolation devices are low pass filters. Putting the equipment in another room is not going to be 100% effective since the entire building is shaking. Hel-loo! Furthermore, airborne vibration from most speakers doesn’t go down below 25 Hz, anyway, so you can forget about it. Besides all tubes are microphonic, even the ones marketed as "low microphonic." Hel-loo!"
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Innocent question: if Sorbothane is really so great an isolator why don’t the big boys at LIGO use Sorbothane? Obviously something’s wrong somewhere. Now, it’s possible that in some density Sorbothane might, emphasis on the word "might", be used as a constrained layer damper. But there are better materials for that application. I suspect Sorbothane is best relegated to running shoes as it apparently is a decent shock absorber. Which as I pointed out before actually makes it a poor isolator. Besides Sorbothane sounds well, funky. It’s not open and natural sounding like competent isolation devices. As LIGO found out after 20 years of isolation system development, there’s really no substitute for good old mass-on-spring techniques. Besides mass on spring devices routinely get down to 3 Hz performance and can be as low as below 1 Hz. Accept no substitutes. Finally the suggestion that Sorbothane can isolate down to 5 Hz is patently absurd since nothing can provide 100% isolation at 5Hz. Isolation is always a low pass filter. Of Sorbothane could isolate to 5 Hz LIGO would be using it.
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For the man with the particle board cabinet: something tells me you’re not a candidate for a Minus K isolation platform so here’s a cheap DIY isolation system for the CD player - Super Balls in Snapple bottle caps. Yeah, baby! |
Isolate the CD player. That will protect it from floor borne seismic vibration as well as vibrations from the cabinet produced by all sources including airborne. |
I have good luck with crystals of various types and sizes inside speaker cabinets.
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