What is more accurate: magnetic anti-skating, or barrel weight attached a fishline?

Dear @ct0517 :   """  7,630 posts Raul and not one that I have seen that offers to share information or shows any ability to set up a LT tonearm.  """

I can't understand why you " insist " with the LT subject, no one but a few use that kind of tonearm design. Tonearm designers deciding go for the pivoted ones. Kuzma owners of Kuzma LT tonearm change it for the pivoted 4P.
Analog experts as M.Lavigne or A.Porter changes theirs Rockport Sirius and Walker both with LT tonearms and today use pivoted tonearms with out the need to turn around again for LT designs.

With all my respect to you in your system you just can't be aware of the LT limitations against pivot tonearm designs because for that first you have to own first rate top pivot tonearms not those non-damped very old designs that are not a good example of what a pivot tonearm " means ".
In the other side the levels of IMD in your system is just to high to detect real limitations/advantages. Why? ( I take the information from your published  virtual system. If already changed then my comment is out of focus. ):

those 800 speakers comes at least witjh two issues that goes against top quality performance level: exist in the music signal information an equalizer/filter where that signal information is degraded and if that device is not used then low range speaker response can't meet B&W specs.

In the other side those 800 woofers handle from aroun 300hz and below it incrementing the IMD aside that the FBP 600 was not designed to meet exactly and cope with the specific woofers characteristics. Here you can read about:

https://forum.audiogon.com/discussions/do-you-think-you-need-a-subwoofer/post?postid=310058#310058

If in the future you make a test in your system integrating two active subwoofers in exactly what I posted in that link you will be nicely surprised. You say you are willing to learns, well this is an unexpected opportunity where I'm totally sure you will have NO comeback/NO return after test it. 

Anyway, till today I don't need to change to LT tonearm design so why bother about?, I don't care about and as I said: " AS is not what can makes the differences between both kind of tonearm designs.

As I told you if you are happy with your LT design good for you, I prefer pivot tonearm design.

Regards and enjoy the music,
R.

Raul

I have multiple, adjacent, dedicated music rooms set up using different technologies. The technologies include tape on a Studer which can be rolled between the rooms. These rooms are on a concrete poured floor. If you would like to learn more, and discuss what I have done, please contact me via my AudioGon virtual system. Just click on the Runner.

Dear @ct0517 : I will do.

Btw, I'm always willing to learn and improve my ignorance level.

Regards and enjoy the music,
R.

Dear @ct0517 : I forgot, regarding the 800 set up I think you are using tube amp along the FPBs: is it in this way?

Thank's in advance.

Regards and enjoy the music,
R.

Andrei, Here is how I think of it: A conventional pivoted tonearm is always set up such that the stylus tip overhangs the spindle.  Now think of the relationship between the tonearm, the radius of the LP (from stylus to spindle) and the pivot to spindle distance, as 3 sides of a triangle.  In order for the stylus/cantilever to be tangent to the LP groove, there must be a right-angle triangle formed such that the tonearm and the LP radius are sides A and B of the triangle that must meet at 90 degrees, per the Pythagorean theorem.  In such a triangle, the pivot to spindle distance is side C, the "hypotenuse".  Pythagorean theorem says that the length relationships of sides A, B, and C in such a triangle must be such that C-squared = A-squared + B-squared.  But, because the pivot to stylus distance is always greater than the pivot to spindle distance, when you posit overhang, this condition can never be met.  Thus, for a conventional pivoted tonearm, the stylus/cantilever can NEVER achieve tangency to the groove.  Headshell offset is a band-aid that permits tangency at two points along the arc traced by the stylus, but as noted above, headshell offset per se creates a geometry whereby there is still some skating force even at the 2 points of tangency.