Comparison of sonic qualities of some tonearms

My question is how do the magnetic AS devices in various tonearms work? Are they all the same, where obviously there is a magnet and either a second magnet oriented so that opposite poles attract or a piece of iron, such that the two fixed points attract each other, or is it more complicated? If magnetic AS is simply based on magnetic attraction, then the force grows stronger as the two points get closer together or conversely weaker as the two fixed elements separate.

I guess neither you nor I want to revisit the "discussion" about the Viv tonearm, but I have to wonder why you (and others like Mijo) are so sure that the enhanced tracking angle error of an underhung tonearm with no offset is so much worse in terms of "distortion" than the enhanced skating force of an overhung pivoted tonearm with offset. It’s a cop out to say that those who like the Viv are merely unable to hear distortion or that they "like" it. Funnily enough, I would say that the main character of the Viv is a sense that there is LESS distortion, not more.

@whart : " But I think there is a level of masochism here that used to appeal to me. "

That’s what mentioned inmy last post but I said it in different way and NO it’s not masochism.

Masochism is different, is " something " that we know is wrong and even that we do it. Example the Kuzma quad unipivot 14" that goes against the cartridge needs in more ways that shorter tonearms.

For me the only " nice " thing in a long EL tonearms it’s how it looks in the TT and I owned the longe tonearms as SAEC’s or FR and a little less longer like the AC or MS MAX. At the end I learned that " ideal " EM in pivot tonearm could be in the 10"/9" EL. where the tonearm bearing react faster to the cartridge tracking sudden groove modulatuions movements that in longer tonearms and not only this critical issue but the dynamic mass in the longer tonearms affects more the cartridge suspension than in a shorter EL tonearms an additional longer tonearms has more surfaces to develop any kind of resonances/distortions than a shorter tonearms but the look is what like the long tonearm owners no matter what. The shorter tonearms are way rigid than the longer ones.

SAT 9" vs 12" paper (swedishat.com)

I think that albert as alan know all those but even that they like it.

Btw and by coincidence Albert bougth it my Audiocraft AC4400 ( the long oneunipivot/dual ) with all its " choices ": counterweigths, different arm wands, etx and the Micro Seiki MAX 282 with all its arm wands (4 ) and everything and not for me but by the person who bougth from me. That MAX Gyroscopic bearing design is a beauty.

Alan prefers the VIV distortions to the other tonearms he owns. In this regards I’m dogmatic as @mijostyn : I can’t buy a tonearm where I know for sure that has higher measured distortions levels as the VIV that other normal pivot good designs. " is a sense ", truly scientific. Look, I'm not talking about the VIv using your experiences just to " hit " you NO I said that you today are and  now that you will be a trusty listener for me.

R.

@mijostyn - I won’t argue about sound engineering principles and do not pretend to be an engineer. I do remember people using arms like the Keith Monks with the old Decca cartridges back in the day. I guess I come back to the OP’s question, which was how to make an assessment of different tonearms. I gave a couple examples, including my use of the Koetsu(s) in a linear arm that does not have high vertical mass (although substantial horizontal mass which is, in theory, relieved by the air bearing). I do not know why the combination of Koetsu and Airline works so well but that’s been my hands-on (ears-on) experience. Ditto my remarks about the comparison of cartridges in otherwise identical arms on the same table. (I suppose @tomic601 alluded to this when he talked about possible variations in build rather than design, but I trust Kuzma enough to get that right).

I have a friend in audio circles who stands by the old SME 3012r as a great all-arounder, and knew plenty of people who, over the years, sought out higher mass arms of old.

@rauliruegas - my comment about "masochism" related to the additional complexities of running an air-bearing arm; the arm itself has been faultless and in service since around 2006. Dealing with the air compressor (I usually use the same Sil-Aire that Franc supplies), running air hoses through walls and dealing with oil based compressor motors just adds more "stuff" you have to deal with as a user. (I’m currently using a different type of compressor and it’s a little less of a headache).

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I have no last word on the subject-- I guess where I come out is that most people rely on anecdotals (or reviews?) based on cartridge and arm since as was pointed out early on, it’s pretty hard to evaluate different tone arms in isolation.

Bill

PS: I forgot to include one amusing anecdote- back in the early ’70s- one of the gang I knew modified a Rabco with a Vestigal arm tube. I have no memory of what it sounded like, since I think he was constantly adjusting it. Total nightmare.

Raul,

I am pinching myself as I ask this question.  My HW40 arm needs to be rewired.  I was going to take it to VPI and let them do it, but should I reconsider?  You are right that the wire I installed in my GAE was Zavfino.  I do not want to do that again.

Lewm and others who might be interested,

When I bought an SL1200GAE it was to replace an SL1200 that had been fully modded by KAB.  While I had both TTs on my bench I conducted a fairly thorough comparison of the two, both in terms of physical characteristics and measurements using a variety of cartridges, a Shure Era IV test record and an O-scope.  Referring to my notes:  The two tone arms were dimensionally identical, weighed the same except I had to first remove the KAB cotton wadding used as damping material,  The material of the arms was aluminum (SL1200) vs. magnesium (GAE).  I was not able to discern any difference in the anti-skating settings.  Technics claimed the bearings to be superior in the GAE, but both seemed similar and I had no way to measure a difference.  Comparing the two arms set up with the same cartridges, however, the GAE consistently tracked 0.1 or better less VTF for the same tracking results as seen and heard during tracking tests.  In listening tests, the GAE had a slight, but consistent subjective superiority to my ear.  Cartridges used:  Shure V-15Vmr, Ortofon 2M Black, Ortofon Per Winfeld. I could hear no cogging, there was no difference in speed stability as measured using a Roadrunner tachometer.  I concluded that the  sound superiority of the GAE was due primarily to the arm and the most obviously difference in the two arms was the material of construction. In any event arms matter.

@whart … for rock solid machining quality assurace, definitely trust Kuzma….