Are linear tracking arms better than pivoted arms?

Dertonarm wrote, "The day a linear tracker shows up which does address the obvious issues of the mechanical model, I am in the first group to buy it. And I will do so before any "sound report" or sonic description by anybody."

Bravo! I will join you if I can afford this potential design, surely will be expensive! Thanks for sticking to mechanic discussion. No, you did not spoil the party. In fact, you have lively up the party. The great filmmaker John Cassavetes once wrote to a writer friend, “Energy bursts out of your writing. I've been thinking about you. The unknown adventurer. Blasting forth through concrete. Blast them. Then love them. Then blast them again...” You see, the blasting and loving is the same thing. Your passion for audio and science is applauded.

The Thales arm and the new sibling Simplicity arm look to have this potential but I do have concern about its extra bearings for the guiding motions to achieve geometric accuracy and hopefully not in the classic case of when the cure is worse than the disease. Regardless, I applaud innovative thinking.

Personally I have given up on the perfect tonearm. I like both genres, as long as people don't tell me their only reason for not liking pivot arm is because a linear tracker tracks more like the cutter head. Maybe I should just go digital. :-)

Just kidding!

This has been an exhilarating thread!

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Hi C1ferrari, I had 2 professional Studer C-37 tubed stereo reel-o-reel machines with about 120 early Westminster, RCA, Mercury and others 2-track 7.5 and 15 ips tapes back in the 1990ies. The rock solid sound of a good r-t-r machine run with a great 2-track 15 ips tape has always been my reference for ohysical presence in sound reproduction. I abandoned r-t-r in the later 1990ies due to lack of supply in original tapes. Furthermore I could finally get the very same physical presence and dynamic from analog cartridge/tonearm and that did it for me. I got insane offerings for my two C37 Studer machines and the tape collection and let them go.

Hi Darkmoebius, I guess we would rather need graphs from spectrometers to show energy storage and resonance built-up in tonearm wands to illustrate the physical issues I was talking about.
Water decay and frequency sweeps will do for cross-overs and speaker building, but not here for tonearm/cartridge issues (or in case they really would do, the respective tonearm's performance would be so poor that it is hardly worth discussing at all...).
My sonic descriptions (I knew that would be coming back against me.... ;-)....) were done to "illustrate" the sonic results of the bearing rigidity and the mechanical problems in linear trackers.
Otherwise you will find very few sonic statements in any of my posts.
From my point of view (sorry for personalizing again..) the mechanical model and the resulting issues (and the lack of addressing designs..) are so obvious that its kind of frustrating.

03-15-10: Dertonarm
Hi Darkmoebius...
My sonic descriptions (I knew that would be coming back against me.... ;-)....) were done to "illustrate" the sonic results of the bearing rigidity and the mechanical problems in linear trackers.

Aaaaah, gotcha, now I understand where you were coming from.

Too bad the thread returns to generalizations & celebration of received wisdom. Mechanics is a system of complex variables. While the idea of an absolutely rigid bearing is comforting, in actual use the performance of a long lever arm is the sum of many forces including its own rigidity & resonant behavior independent of the bearing. In this regard a short arm surpasses a long one. As regards the low effective vertical mass and long travel of a short linear arm, anyone who has set up a suspension for motocross knows that a properly set up long-travel suspension is consistent with stability in tracking bumps. While yaw in some air bearing designs may cause errors in tangency, solutions to the problem are not inconceivable. For example in Ladegaard/Trans-Fi design, the mating surface of the slider is a wing of large 14 sq. in. surface area, whose long parallelism with air manifold enforces minimal yaw--together with minimal turbulence attendant with low air pressure.

This is not to suggest that this arm is the last word in design. Doubtless each type has strengths and weaknesses of theory and operation. Perhaps it is more interesting to consider the strengths and weaknesses of specific implementations than of abstractions. For example, a P2 may be nice, but I believe there are around six mating solder/mechanical joints in signal path through arm wand. Sacrebleu!