Correct alignment for Fidelity Research 64fx/SPU?


Hello,

I've recently paired SPU Spirit with FR64fx (& additional counterweight).

FR64fx is mounted at 230mm pivot to spindle distance on my Garrard 301.

I currently experience a light distortion and mistracking. As I tried the SPU before on almost ad hoc mounted 3012 and that sounded technically correct (though not as convincing as with FR64fx in terms of emotional performance), I'm pretty convinced I will need to realign the tonearm.

I would appreciate any info related to an experience of 64/SPU users here, which would differ from a usual 230m PTS alignment. Also, I keep on reading that Stevenson alignment would be preferred, is there any explanation why so?

Basically I need to make a good decision as I have no armboard - whatever decision I make I will need to get a new top board with a new hole for a new alignment.

Many thanks!
anubisgrau
LOL....yes mm and not cm. I set all of my cartridges to 50mm stylus to mount distance and the SPU is just plug and play.
50 cm is equal to 19.6 inches. 2.54 cm per inch. Whew! I'm glad I got that off my chest.
Very late to this one but 52mm is the stylus to arm collar distance on an SPU. People working to 50mm are going to get a nasty tracking error.
The alignment of FR64 arms with integrated headshell cartridges is pretty straight forward. Ikeda designed the arm to accomodate his FR7 cartridges with integrated headshell allowing 51mm stylus to arm collar distance. When you observe the specified 230mm spindle to pivot distance of the FR64 you get perfect alignment with the Stevenson geometry. This set up has the convenience to also operate SPU's without having to change the S2P distance. This suggests that the stylus to arm collar distance on SPU is also supposed to be 51mm. Perhaps Ortofon has changed this recently, but my SPU's have 51mm and fit the FR64 perfectly. No tracking errors.

 To add to some original comments made regarding 
the SME 3012 and its suitability or not, the specific reference
was to the R version and differs from the standard 3012 model
quite a bit.

The R series was modelled after the first series 1, 3012 circa 1955
which differed in both mass and materials used for the arm tube. 

Comparing any 3012 to other than the original rare series 1 or 
the JDM R version is apples and oranges.