Correct alignment for Fidelity Research 64fx/SPU?

Lewm, I've been at this for years now and spent enough time comparing arms and cartridges on high end tables to finally settle on the 3012-R, and yes the cost is also important. At any given time I have 16-20 arms setup on various tables, aside from sounding great the 3012-R is the most flexible and most economical too.

Syntax, it's not a fact at all, only your opinion. Technically the 3012-R's
sliding base makes them much more flexible and accurate setting tracking
angle on various cartridges, you're much more limited in your cartridge with
the FRs. Where do you get limited to Shure system from? I have everything
from Shure to Neumann DST set up on a pin modified 3012-R and they all
work and sound fine.

Yes alignment is an issue with FR arms with many cartridges, fx and steel
tubed, that's a design flaw. You can also add arm leads, mats and even belt
tension to your list of things that can affect comparisons. Garrard's
vibrations can be mitigated with a properly designed and built base
and even go further by having standalone arm bases which allow more
flexibility of alignment for FR/Ikeda arms. But the Garrard is colored
and not the ultimate in resolution making this kind of assessment difficult. In
my case I lived with FR66s and 64s for many years and had them sitting
side by side with 3012-Rs on the same tables, SX-8000mk2 and American
Sound AS-1000x, the most neutral and natural sounding table I heard or
owned. I find the 3012-R superior, specially in the low in the lower
frequencies. Let me add that I don't like the sound of silver wires and my
FRs are all wired with it.

I'll bring this back to your original question: "correct alignment for the arms designed by Ikeda son." All of his arms are optimized for Stevenson alignment, this is the only alignment method that he uses. I purchased a Mint Protractor and have absolutely zero tracking error with my SPU, Shelter 5000 or Denen 103r.

The downside on the Mint is that you can't vary the spinal distance. Dertonearm recommends the 231.5 distance on the FR64, you will have to buy a different protractor.

Question to those who use SPU:
Isn't there something "funny" about this cartridge, such that the tonearm has to be adapted for proper alignment, or something like that? I think it has to do with the distance between the rear of the cartridge body and the stylus tip.

Dear Jeff, Regarding the 'original question'. I prefer to
put this question otherwise. Not as 'what is the correct
alignment' but as 'what is the optimal geometry ' for the
64 series? After all both , Stevenson and Bearwald should
be considered as 'correct' but, as I mentioned in my reference
to 'Das Ohr' Magazine and you to Dertonarm the
'optimal distance' should be 231,5 mm. But this means
Bearwald geometry as well the assumption that Bearwald is
'optimal' and consequently that Srevenson is not.