Graham Phantom Supreme?

Why would Bob Graham knowingly produce an alignment jig that is off for the 10" & 12" arms ? How much error are we talking about ? To my ears, the alignment sounds perfect...No audible distortion through the lead out groove. Too bad Graham didn't put a detent on the center of the pivot cap so that I could use my feikert. Anyone have an idea how to measure for the exact center point so that I could make my own detent ? I am going to inquire with Graham directly about this.

Dear Hiho, it is the off-set angle at the headshell mounting area. The problem here is, that the off-set of the mounting area is too large for the 10" and especially so for the 12" arm wand.
Resulting in additional and unnecessary breakdown torque as well as in an odd position mounting of the respective cartridge.
In an uni-pivot like the Phantom the bearing has no off-set - just the mounting area has ( here off-set is a function of the geometry and effective length ). The smaller the off-set angle is, the smaller the breakdown torque is.
That's one of the reasons why longer pivot tonearms do sport less skating force.
Hope I am not too obsessed with minute detail here ...;-) ....

Dertonarm: "In an uni-pivot like the Phantom the bearing has no off-set - just the mounting area has."

Actually there is an offset angle at the bearing with semi-unipivot designs like Phantom (or Basis Vector, Continuum Cobra/Copperhead, etc.. in the same genre) because there's a secondary bearing to stabilize azimuth so if you draw a line between the main bearing and the secondary bearing, it is offset at an angle matching exactly like the headshell. This clever design allows the azimuth adjustment having no effect on VTA. Same concept in many fixed bearing designs.

A true unipivot like the earlier Graham arms, such as 2.2, used offset angled outrigger weights to do the same thing, and since Graham has a patent on this feature, you don't see other arms doing that.

Anyway, thanks for explaining about the Supreme headshell issue.

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Here is a picture from

Graham 12'' Phantom IIs

The red signs are coming from the timeline Strobe (speed controller)

Dear Hiho, you're right.
I forgot - the Phantom is a semi-unipivot design.