Raul, do you have any data, besides the capacity to measure TAE, which is obviously greater for an underhung tonearm than for a conventional pivoted tonearm? What measurable data correlate with distortion of the perceived information we can get from an LP to the degree that the information encoded has the potential to result in the presentation of real instruments in space?
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What Dave said.
Also, the supposed purpose of the decoupled headshell on the RS Labs is largely defeated by its wiring, which impedes free motion about the horizontal pivot of the headshell. (Here I’m referring to the rearward decoupling of its headshell. Dave is talking about the flat surface to which the cartridge mounts, which also moves in the horizontal plane.) I’m not saying this is good or bad. The RS headshell can actually be purchased separately. Couples to any conventional tonearm.
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Again, I’d prefer to compare underhung tonearms to conventional pivoted overhung tonearms. And my thought is that the more linear change in skating force from outer to inner grooves may be an advantage to underhang. Also zero headshell offset may be another. I’m just trying to understand why SQ is good, and I mean audible distortion is low.
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Raul, I apologize; the technical explanation for the underhung tonearm on the GT5000 is to be found on the "What Hi-Fi" review of the whole turntable, where the reviewer asked the Yamaha engineers for their explanation. He then had to translate the response from the original Japanese:
I thought I should ask Yamaha about its rationale for the tonearm length and the lack of anti-skating, and received a reply from no less a personage than Kiyohiko Goto, Chief Engineer at Yamaha Japan’s AV Division.
Regarding the tracking error he says: “A short straight arm has excellent tracking performance because the inside force is generated at the point of contact between a stylus tip and groove of vinyl and is always variable with the variate of the music groove. In the case of a short straight arm, its null point (= balanced point) is at the middle of the grooved area (so) the maximum tracking error is 10 degrees at innermost and outermost grooves. The distortion caused by this small error angle is inaudible because it is lower than both the tracing distortion and the residual noise. Furthermore, tracking error appears as phase shift between the left and right channels, and even at its maximum (10 degree) error the phase shift that results would be the same as caused by a difference in the distance from the left and right speakers to the listener of only 2mm. This also does not cause any problem for sound.”
As for the lack of anti-skating, he says: “A short straight arm does not require anti-skating because [at maximum error angle] if the vertical tracking force is 2g, the frictional coefficient is 0.3, and so the inside force (outside force) will be approx. 0.1g. In the case of a conventional offset arm with a maximum tracking error of 2 degrees, the inside force will be approx. 0.02g so the difference of the max inside force between a short arm and an offset type will be 0.08g at the maximum, thus the difference in force is very small.”
“On the other hand, when anti-skating is employed, because it applies a constant force it never cancels the inside force which constantly changes as its follows the music signal. The constant differences between the variable inside force at the stylus tip and the constant force by the anti-skating adversely affects the cantilever, hence the tracking performance is not stable. In a short straight arm the tracking performance following (the) music groove is excellent because the variable difference of force between the stylus tip and tonearm (cartridge) is not generated.
In my opinion, the real reason there is no anti-skate device is because AS would have to reverse direction by 180 degrees, before vs after the stylus gets passed the single null point achieved with any underhung tonearm. That would be difficult to manage. Whether AS per se is harmful for the reasons stated by the Yamaha engineer is a matter for debate. Whether distortion due to TAE is lower in magnitude than both tracing distortion and residual noise is an interesting claim that I am not equipped to critique. The bold type is mine in order to highlight that controversial claim. If the claim is valid, perhaps that explains why I hear no problem that I can relate to the extreme TAE, with my RS Labs RS-A1. In fact, the character of its sound across the surface of an LP, from outer to inner grooves seems more constantly the same than with conventional pivoted tonearms. This is only an opinion based on listening and with no measured data, of course.
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Raul, Can you get it through your head that I am not claiming superiority for underhung tonearms? I have written this many times. I am only advocating an open minded approach to novel ideas, such as the idea of an underhung tonearm. And in fact, how DO you know that a pivoted, overhung tonearm with headshell offset is the best option for pivoted tonearm design, besides linear tracking, unless you at least entertain other designs? Have you auditioned the Viv or any other underhung tonearm? Actually if you go to the Yamaha GT5000 website, you can find there a decent scientific justification for the underhung tonearm on that turntable, albeit I take issue with some of the points made there.
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The Viv and its unique design qualities have nothing whatever to do with the Schroeder or Reed pivoted tangential trackers. Why do you constantly choose to compare the Viv to those specialty items? It’s more interesting and on point to compare the Viv and any other underhung tonearms to conventional overhung pivoted tonearms. I take it as a given that the Reed and Schroeder are likely to outperform the Viv, but the former two are very expensive. And a listening test would be most informative. Results might surprise all of us.
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Booth, Not sure what you mean. A spherical tip still generates a skating force, if that is what you're suggesting.
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Mijo, I am talking about underhung tonearms as a separate subject relative to the Viv tonearm. Whether the GT5000 is totally to your liking or not is not the point, but I did notice that the tonearm design on the GT5000 does have the technical flaws you mention. As previously discussed, the placing of the pivot at the level of the LP surface, or lack thereof in this case, has relevance only with warped LPs. To which you may reply all LPs are warped to one degree or another. To which I would reply that really tiny or minimal warps are also really tiny and minimal problems in terms of altering VTF. Anyway, neither of us is going to buy the whole turntable just to get an underhung tonearm. All that said, I would be very curious to hear the GT5000 in a good system.
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Raul, when you align an OVERhung tonearm and set headshell offset angle to zero, as you did out of necessity, that is the worst possible scenario, so it’s no wonder the SQ was poor. For an overhung tonearm, there can be no null points on the surface of an LP unless the headshell is offset at an angle, as determined from any of the standard algorithms. You can prove this with reference to the Pythagorean Theorem that we all learned in high school. That situation is not comparable to using an UNDERhung tonearm and zero headshell offset angle. I seem to be coming off as a defender of the Viv; I am not necessarily taking that position. I only have concluded there may be some good things about underhang and zero headshell offset and the resulting pattern of the skating force. I am urging an open mind. Even the "distortions" that you consistently preach against may be worse with the standard pivoted tonearms than with an underhung tonearm assuming the latter is properly set up. I only wish there was an underhung tonearm that does not also have other unusual features. For example, my RS Labs has many issues that may affect its SQ and have nothing to do with its being underhung (raised unipivot way above the LP surface, dangling counterweight that is free to swing back and forth, decoupled headshell). The Viv has its pivot floating in an oil bath and an arm wand that looks prone to resonate, albeit the oil bath might provide some damping. I have never heard the Viv, but I can report that despite its craziness, the RS Labs can sound very colorless.
Yamaha has recently introduced a new turntable, built to look like the GT2000 but with belt drive, I think. It comes standard with an underhung tonearm with a zero offset headshell. From photos, this appears to be a nicely built tonearm that is otherwise in keeping with modern concepts of tonearm design (i.e., lacking other features of questionable merit). If Yamaha would market that tonearm as a separate product, I would be most interested,
By the way, Neon, your fears of using the MC2000 in your DV tonearm are groundless. I've mounted the MC2000 in my DV505, and the results were excellent. Right now, it is mounted on my Triplanar, but not because I was unhappy with the DV505.
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I don’t disagree with Atma; the physics that suggest you need to tightly couple the tonearm pivot to the TT bearing is inescapable. However, there are many other "rules" that govern modern tonearm design, any one or several of which might be violated if one were to do a close analysis of any single design. The question then is what is the order of importance of these rules with respect to ultimate sound quality with a reasonable variety of cartridges. And what are the negative consequences of violating one or more of those principles? I think you then have to listen to the tonearm in action to determine its goodness. I have already stated that I wonder about the floating bearing (is the pivot well fixed in space? That’s another imperative.) and the skinny undamped arm wand (Will it resonate?) Yet the Viv float has been reviewed many times, and I don’t know of any reviews that were less than enthusiastic. We have already heard from two users of the Viv that they like it quite a bit. So it may be a "bad design", but it sounds good to most who have auditioned it. Certainly one does not want to dismiss such a product out of hand.
I might add that the Viv has a weighted base, and it is designed to be placed on the surface of the plinth, adjacent to the platter. Thus it IS to some degree physically coupled to the bearing, to the degree that the plinth and bearing are tightly coupled, and the plinth will move if the bearing is disturbed. So maybe the coupling between arm and bearing are tight "enough".
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The RS Labs is the same in that regard: it is not rigidly coupled to the bearing. I agree that’s another rule breaker. Now we have to listen to the Viv. In all the other respects in which underhung tonearms like these two are rule breakers, it is possible that the rules that they break ( minimize tracking angle error, etc) are themselves not as crucial to best performance as we have been taught to believe. I agree, the notion of coupling of the pivot to the bearing is a design element I would rather not forgo. But even there, there are many who use outboard arm pods with overhung tonearms, and there are several turntable/tonearm combinations that pay little attention to that coupling. We have gone over that idea more than enough by now.
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Clearthinker, once in a while you don’t live up to your chosen moniker. But disregarding clarity of your thinking, have you found a single negative review of the Viv?
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"Skating force may not be an important factor in tracking error."
To unpack your statement a little bit, skating force is in part directly proportional to tracking angle error. The term "in part" enters into it if you are using an offset headshell. With no headshell offset angle, then skating force is directly proportional to tracking angle error. Think about it.
Really, why would we care about Ikeda-san’s opinion of the Viv? Can’t we form our own opinions by listening to it? He could tell us about its technical "shortcomings", to the degree the design differs from that of any conventional overhung tonearm with a headshell offset angle, but those are obvious.
Why does exotic audio gear cost so much these days? Probably because the sellers think enough of us will pay their prices to justify their costs and need for profit. But this has nothing to do with good or bad performance, in my opinion.
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I would have imagined it might outperform the 3012R. The 9-incher in CF would be my choice too. Last time I was in Tokyo, prices there were about 60% of US prices. Still, more than $3K for the above version.
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I see that the usual "open-minded" suspects are only too eager to support the status quo in favor of a very interesting departure. First, the Viv does not have "zero" overhang; it is UNDER hung; designed so the stylus tip is a certain distance short of the center of the spindle, and there is a reason for this. By being underhung, the single null point can be set to occur in the middle of the LP surface, or wherever one decides is optimal. Second,the only parameter that can be calculated "mathematically" is tracking angle error, and both Jason and Mijo are obviously correct in stating that the Viv will exhibit much more tracking angle error than a conventional overhung tonearm (but see below). Skating force: the Viv and other underhung tonearms of which there are very few will exhibit zero skating force at its single null point, unlike overhung tonearms with headshell offset, which never exhibit zero skating force, because even at their two achievable null points, there will still be skating force due to the headshell offset angle. Further, the skating force vector generated by the Viv will be a more or less straight line, starting with a force toward the spindle and diminishing to zero as it crosses the single null point and then changing direction as the stylus moves beyond the null point, when the force vector points toward the rim of the LP. (This is why you won’t see an underhung tonearm with an anti-skate device; it would have to change the direction of the pull by 180 degrees at exactly the right moment.) The skating force of an underhung tonearm follows a smooth nearly linear curve if plotted to show magnitude and direction. Overhung tonearms with headshell offset have a constant, constantly changing skating force vector (and tracking angle error), always pulling the stylus toward the spindle but by wildly different magnitudes across the surface of the LP. Is one more audible than the other? I have no idea, but I do know that my wierdly designed underhung tonearm, the RS Labs RS-A1 sounds very good, and if I had to characterize the SQ, I would say it sounds closer to a master tape than do conventional tonearms. Maybe this indicates that zero tracking angle error is not the Holy Grail some claim it to be. The Viv has some other design aspects that I wonder about, like the pivot floating in an oil bath and like the arm wand which looks prone to resonate. I also think it's a bit overpriced in the US market, much less costly in Japan. But it has received many accolades from reviewers who are not stupid. And then too, I admire my RS Labs for its SQ, although the only thing it has in common with the Viv is its underhung-ness.
One wonders what sort of record player Rabinow et all were contemplating when they did their math in the 1930s. Half the world was still using wind-up Victrolas in that era, and no one had stereo of course. Same goes for the sainted Baerwald and Lofgren, who published their papers in 1940, 41.
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