Linear tracking turntables, whatever happened?

I've seen photos of Dave's work on the Trans-fi.  I was very impressed.

 First of all, what makes you say that the idea of linear tracking is dead? While there are not many all in one linear tracking turn tables on the market these days, there are still several high-quality linear tracking tonearms available. And as someone else has already mentioned, one of the best is the  trans-fi  terminator. It was off the market for a while, but I now believe it is for sale once again. As to the problems, everything of a technical nature has its pluses and minuses. So for a linear tracking tonearm, the problem is to drive the tonearm and cartridge across the LP surface,  some sort of for force is required. That can be in some cases a servo motor, in some cases gravity, and in some cases just an attempt at zero friction back at the pivot point.  Usually extremely low friction is obtained by having the pivot point on an air bearing. Many different types of air bearing have been tried, and most of them work to one degree or another. People argue about whether low pressure or high pressure air is best, for one example.Then there are other issues like what is the proper length of the tonearm? At least some devices attempt to ride the cartridge very close to the stylus tip, with almost no “tonearm“. All of these solutions have their pros and cons .

And Harold, Whether you like it or not, there is no such thing as "friction-less" in the real world.  Ergo, if the groove is guiding the stylus tip, there is a side force generated at the stylus due to friction at the junction (and the mass) between the arm wand and the tube upon which it rides. Albeit the best air bearing tonearms are pretty successful in minimizing this problem.  Why is it so upsetting to mention that?

Ct, In the absence of any friction at the pivot point, yes there is no need for any external force to move the arm wand/cartridge across the LP surface.  However, in the real world, there is never zero friction.  Thus we first had the Rabco SL8, referred to by Ralph, which used a servo motor to nudge the pivot each time the arm wand moved in tiny arcs at the stylus contact point; the Rabco makes a series of tiny arcs all across the LP surface, the servo motor makes noise, yadayada.  Arguably, it's not even a true SL tonearm.  The Goldmund TF tonearm is naught but a very expensive copy of the Rabco idea.  We also have the Souther tonearm which operates in concert with a "dished" platter (marketed in recent years by Clearaudio), so that the cartridge "falls" toward the spindle whilst riding on a rail.  The most pure form of the art is the air bearing type, which at least strives for zero friction.  But since that is impossible, side forces are created, as described by Ralph. In addition, one must fuss with air pumps, etc. But certain examples, like the Terminator, can be very good. I don't need to own an SL tonearm or turntable in order to know these things.  What about you?

The only full bore turntable/SL tonearm available now comes from Germany, I think, but I cannot recall its name.  Another German company, Brinkmann may also make one.

testpilot, Thanks for supplying the name of that company, Bergmann.  If you re-read my post, you will see that I mentioned first that there was one German company I could not name, and second that I thought Brinkmann might also make an all-in-one SL turntable.  On that score, I may be right or wrong.

Ct and Harold, NO, as I mentioned, I have never owned an SL tonearm.  And NO, I don't categorically dislike the idea.  I have had a long-standing interest in the Trans-fi Terminator, which you can probably verify by doing a search here.  I have heard it and other air-bearing tonearms many times, and I agree they have a lot to offer. Up to now, if I were to want to experiment with an SL tonearm, the Trans-fi would still be my choice.  I do have an opinion that the Rabco SL8, which I have heard many many times, and the Souther are not the way I would go.  These are my opinions.  So sue me.

Dear Millercarbon, Thank you for "telling it like it is".  I've never heard those gaudy products all together in one system, but I can imagine that I might agree with you, if I were to audition that system.  However, let's do keep in mind that the Clearaudio turntable uses a Souther-type tonearm, described by me in an earlier post.  In fact, I think Clearaudio bought the patent rights from Souther in order to incorporate his ideas into their products.  In my opinion (and I stress that this is ONLY an opinion), the Souther design, where the cartridge is carried on what amounts to only a headshell which rides in a gravity-dependent fashion on a rail strung across the LP surface, has many issues.  Not the least of which is that any irregularity in the LP surface has a large effect upon VTA, due to the very short distance between the stylus and the headshell pivot point.  My point is that I would not throw the SL tracking baby out with the Clearaudio bath water.  SL tracking done well does have merit.  I think air bearing is the way to go, but like many others who joined this thread, I chose not to bother with the air pumps, filters, and noise that come with air bearing tonearms.  I do recognize that by choosing to use only pivoted tonearms, I am accepting one set of problems for another.

Please tell us what Rabinow did with coat hangers to prevent a toilet from being flushed while the train was in the station. Inquiring minds want to know.

sgunther et al who use the Terminator: The most knowledgeable guy I know as regards the Terminator is Dave Garretson.  He devised a novel way to reduce drag of the wiring on the movement of the arm and he also manufactured a novel arm wand with adjustable effective mass and reduced resonance.  All this was done under the aegis of Vic. Perhaps you know all this.  Dave is a member here.