Angling for 90° - tangential pivot tonearms

[robertmc48]

Sad to say I have no information about this tonearm. I have had a search on Ebay for about 10-12 years and one has never come up. I don't even know if it has a model number. I had it playing tonight and it plays very nice.

[directdriver]

Originally Posted by robertmc48

It is a JVC Nivico Perfect Tracking. In all that time I have never seen or heard of another one except for one sold in Malaysia. It is a large turntable probably made in the 1970s. The most interesting thing about it is the tonearm. It is a tangential tracking arm. It is nicely made with a jeweled movement.

Wow. Thanks for posting and sharing with us such an interesting tonearm. As others have mentioned, it looks to be a Japanese copy of the Garrard Zero 100, except the guiding rod is on the left side of the main armwand, whereas Garrard is on the right. Looks like better pivot quality and well constructed. And the anti-skating uses a more conventional string and weight design than magnets. To me it's more attractive than the flimsy Garrard.

Thanks again!

[directdriver]

Originally Posted by robertmc48

In all that time I have never seen or heard of another one except for one sold in Malaysia.

[directdriver]

Robertmc48, I hope you don't mind that I am reposting larger size pictures of your JVC Nivico turntable from another forum:

[robertmc48]

I am glad that some of you have enjoyed seeing this turntable. I have owned it for about 25 years and it always gets a lot of comments when it is seen by someone who appreciates turntables. I have owned many turntables over the years but this one remains a favorite. I think it looks better in person and it really does work and sound good.

[directdriver]

I posted this before about this hypothetical design that the vertical bearing does NOT pivot. It's "pistonic" and it moves up and down without changing tracking or raking angle. It's like a linear bearing for vertical movement. I wonder if we use miniature linear bearing for the vertical plane, the horizontal mass can be significantly reduced and we can then use another set of linear bearings for horizontal movement or a use pivot bearing. The advantage of vertical linear bearing is that gravity doing the tracking force and use a string or spring to push or pull up the headshell assembly as a counter-weight. On a tangential pivot arm, the armwand only has to move horizontally sort of like the Dynavector arm.

Work is underway on the nextgen of innovation, a maglev linear tracking & "armless" design (pictured below). It's sans an “arm” tube or wand, utilizing a vertical hydraulic piston with internal magnetic dampening. The stylus cannot leave perfect tangent & the piston is sans relative mass, only tracking force. It cannot “teeter-totter" as in pivoting or linear tracking "armed" designs. No other design maintains perfect vertical tangent and azimuth alignment, and it's linear maglev!

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I know the "teeter-totter" effect was something objected by the late Bo Hansson, designer of the Opus 3 Cantus linear tracking tonearm, hence the lack of pivot point for the vertical movement in the design.

The manufacture has since deleted the page so I guess they aborted the project due to either technical difficulties or too expensive as an investment. It sure gave me food for thoughts though.

Whaddaya think?



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[directdriver]

The JVC Nivico and Garrard Zero 100 tonearm bearings reminds me of the Thales Simplicity tonearm. Comparison below.









To further simplify it (pun intended), wouldn't it be easier to use TWO unipivot bearings? To me, it begs for such bearings.

Whaddaya think?



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[stevieg]

To further simplify it (pun intended), wouldn't it be easier to use TWO unipivot bearings? To me, it begs for such bearings.

Whaddaya think?

You will still have the two bearings at the headshell end. Possibly varying amounts of play/friction will caused the unipivots to rattle?

Cheers Steve

[directdriver]

Originally Posted by stevieg

You will still have the two bearings at the headshell end. Possibly varying amounts of play/friction will caused the unipivots to rattle?

The advantage of a unipivot is that the contact point is preloaded and has the least amount of contact area, a single point, hence low friction. Even Michel Huber of Thales admitted his double cardanic bearing has the lowest possible friction but NOT lower than a unipivot.

Michel Huber in an interview: "Our tangential pivoted construction can compare with any ball bearing design regarding friction, but not with unipivot tonearms as they have only one contact point."

They will not rattle due to the preloading and it will simplify the geometry. And having two unipivot points they stabilize each other in the azimuth plane. Then at least we can concentrate on the quality of the headshell bearings. Once the base pivots are taken care of we don't have to worry as much and focus on whatever headshell design we can come up with.

For a dual-wand design, using two unipivots at the base is the simplest and most effective solution, to me at least. The creativity and design ingenuity is in the headshell pivots, which is another topic on its own. While I love the look and design of the Thales Simplicity design, I would still prefer one main rod that has majority of the mass and one smaller rod for guiding. The equal mass armwands design of the Simplicity or Van Eps arm is too technically difficult to materialize in a DIY project.

To simplify simplicity is not so simple after all.



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[AuroraB]

Alarm clock type adjustable jewel bearings?