If you use the 231.5mm S to P distance for the FR-64s.......you will not be able to interchange headshells onto the FR-66s which is best set at 295mm.
I prefer to set my FR-64s at the FR recommended 230mm S to P to match the 295mm of the FR-66s.
And yes......I have listened to the differences between the 230mm distance and the 231.5mm.........
However I don't think this will solve the problems you have described Suteetat?
I have plenty of 'play' distance for all headshells I have tried on both my FR arms to align for ALL the known geometries.
Something appears amiss in your story?
I prefer to set my FR-64s at the FR recommended 230mm S to P to match the 295mm of the FR-66s.
And yes......I have listened to the differences between the 230mm distance and the 231.5mm.........
However I don't think this will solve the problems you have described Suteetat?
I have plenty of 'play' distance for all headshells I have tried on both my FR arms to align for ALL the known geometries.
Something appears amiss in your story?