Fidelity Research FR64s Headshell dilemma

Bu why do you change manufacturer recommended PS from 230mm to 231.5 mm ? 

This 1.5mm can be easily adjusted in the headshell with recommended 230mm PS

Dear chakster, what you overlook is difference between zero (0)
points on the record surface between those two geometries.
Bearwald has the best áverage values for all surface places
while Stevenson has better value for the inner groves. You may
have records hith inner groves which ''ask'' for Stevenson. But 
the most people prefer better solution (values) for all groves. 
As I mentioned before you attribute to manufacturer to much
''authority'' with illusion that they know better,
By scientific arguments used by Kessler and Pisha all 22inspected
tonearms  have sub-optimal solutions for prescribed parameter.
I hope you can find their .article (Audio Jjanuari 1980) and see
for yourself. ''Belief'' is not an scientific argument. 

@nandric PS has nothing to do with Baerwald, i can re-align any cartridge on conventional headshell with slots on FR tonearm without changing PS distance. I do NOT change PS when i re-align between Baerwald, Stevenson or Lofgren, it’s all about cartridge position in the headshell, not PS which must be fixed to 230mm on FR tonearm, same with Ikeda tonearm.

Anyone who use Dr.Feickert protractor can do that too, no need to change PS distance to change alignment method.

Stevenson case has been discussed million times on audiogon. Actually it was made for classical music you’re listening, not me.

I have many tonearms and use them according manufacturer recommendations, some of my tonearms such as Reed is always Baerwald, my Lustre GST 801 realigned for Baerwald without changing PS distance. My Denon DA-401 aligned with its own method and i like it. What else ? Technics EPA-100 mkII is very close to Stevenson like almost any Japanese tonearms and i can't detect any single problem with many cartridges.

Using FR-7 or SPU series on FR tonearm everything is just perfect as it is with manufacturer recommendations, PS according to the manual.

Dear chakster, your ''theory'' imply that one can chose spindle
to pivot distance as one like. But pivot to spindle distance determine
eff. length. By Stevenson 245 mm by Bearwald 246 mm. If one 
could chose eff. length as one please we would not need tangential
arms because all points on the record would have zero angular error.
Your Feickert can't correct all the errors manufacturer made. 
As I mentioned by Kessler&Pisha all 22 inspected tonearms have errors. 

By Stevenson 245 mm by Bearwald 246 mm

This is why a cartridge must be moved just a little bit forward in the headshell and a little bit turned to the side to align by cantilever using lines on the protractor.

As i said earlier there are many turntables with fixed tonearms, you can’t change PS distance, but you can change alignment method moving a cartridge only (in the headshell slots).