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In Reply to: Also, check this out posted by Doug Deacon on August 6, 2005 at 09:33:38:
I haven't tried it but it shouldn't have an effect on effective mass.One could also consider the tonearm wand to be the tightrope walker's balance bar. The rotation is on the vertical axis. so placing the weight of the bar (wand) at the extremes will have the same effect. The wand will not easily rotate but it the mass is centered close to the pivot (vertical axis) then it will rotate more easily. It's total mass can more easily be moved left and right.
All things being equal my Schröder arm sounds better with a heavier headshell (I have a couple) and counterweight moved further from the pivot than the opposite.
A few grams of additional headshell weight will not generally lower the resonant frequency significantly but will allow the c/w to be located further from the pivot. I know it's blasphemy. But considering the results I and some others have achieved with locating the masses at the extremes I can't imagine the leadweights at the pivot would have the same results since they are located at the pivot they shouldn't add to the mass thus not changing the inertia. I'm not saying it doesn't do what is claimed but ask why?
But now I ask where is the inertia the greatest? Inertia being the resistance to movement. That object with the greater mass has a higher resistance to movement.
The stock 300 C/W is 100 gr the HWs are 145 gr (at least one of two I have) and I also have a special "Lightweight" that is 110 gr. So the heavier HW will lower the effective mass since it is on the negative side of the pivot point.
Maybe those outrigger weights should be "way out there", huh? What do you think? I'm serious.
Follow Ups:
You just need to get your head around it.From the POV of the vertical axis, the mass of the fishing weights is just one more component in the total effective mass of the structure that is attempting to rotate around it. Whether that mass is at the headshell, at the c/w or elsewhere, its all part of a single, rotating structure. Adding more mass or moving a mass farther from the axis increases the effective weight of the entire structure. It's just a matter of degree.
The other day you argued that a small headshell weight would only alter resonance frequency 1 Hz or so, so it wouldn't effect sonics much. I had to explain that the greater INERTIA from raising effective mass allows greater cantilever deflection, and therefore greater signal output, before RESONANCE even begins.
Now you quote an identical experience back to me. Yet you still don't see that raising effective mass by another means would have a similar effect?
I despair...
__________
"Do not meddle in the affairs of wizards, for they are subtle and quick to anger." - JRRT
I was responding specifically to someone with a VPI arm which had a very high RF with a given cartridge. One of the possible "fixes" ws a 3 gram or whatever weight from VPI which in THAT particular combination would have lowered the RF 1Hz or less. given the problem not really worth the effort.I never said that increasing the mass at the extremes of the arm would not increase the inertia, in fact it does.
As for the fishing weights the amount a given amount weight effects the effective mass is proportional to the location relative to the pivot. In other words the 1 gram at the headshell has a much greater effect than 1 gram at the exact pivot point. It may increase the rotational mass without increasing the effective mass.
Now that can be a very interesting change in the arm mass but not the effective mass.
Hey Garth,I didn't know you had a Schröder. How do you like it? Is it really as good as many people say? If so, what do you think makes it so great?
the virtually friction free "bearing", as you know it's literally "hanging by a thread" and the damping of the magnets. They make the movement of the arm very stable as if it had much more mass than it actually does. The headshell design is also pretty clever and a breeze to setup.
One is stationary the other on the armwand and their attraction is the damping, as opposed to an oil bath or silicone bath for instance. This magnetic force(s) stabilize the arm in all planes. It is amazing how "stiff" it feels yet how easily it moves.
Just funnin' with ya' John.The gap between the magnets is also adjustable. The string suspending the one that supports the armwand is on a threaded mount. Turning the screw raises/lowers the upper magnet and adjusts the gap. The closer the magnets, the stronger the attraction and the greater the damping. It's very cool.
Even more cool is the resonance damping of that wooden stick. I think the Reference is the quietest arm on the planet. The noise floor is lower than my TriPlanar's, lower than your SME's, lower than any arm I've heard. That's even more cool, from a musical perspective anyway.
__________
"Do not meddle in the affairs of wizards, for they are subtle and quick to anger." - JRRT
I think magnets are a great tonearm stabilizer. Even the new Graham unipivot uses magnets to stabilize the design.I know Garrard played with this a bit in the mid and late 70's I had a Garrard Zero 2000 B with magnets to control the antiscate. As cool as the Zero 2000 B concept was, a good straight tonearm just wiped it in terms of sound quality.
I wish a really good manufacturer like Micro Seiki would have tried a similar style arm. Maybe they did and abandoned the idea LOL.
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