Hi, Swampwalker; pivot to stylus distance is not really variable with the Pro-Ject 9 series tone arms. The headshell was designed such that installing a cartridge with typical mounting holes will put the holes at about the midpoint of the headshell slots and the stylus at the designed 230mm effective length. The slotted headshell allows for a range (~6mm) of cartridge mounting hole configurations but there is only one correct effective length for the intended alignment geometry.
If the distance from the pivot to the center of the headshell slots (~220.5mm) is grossly different for the OP's Pro-Ject 9cc tonearm, then the stated 230mm effective length may be in error. As to whether the pivot-to-spindle distance is grossly different than the stated 212mm, it's an easy task to measure that distance on the Pro-Ject 'arm. I get ~212mm with an aluminum 9 tonearm installed on a (Pro-Ject) mmf-7 turntable.
If Wilson667 takes a few quick measurements it may eliminate a couple of the obvious variables.
Tom
If the distance from the pivot to the center of the headshell slots (~220.5mm) is grossly different for the OP's Pro-Ject 9cc tonearm, then the stated 230mm effective length may be in error. As to whether the pivot-to-spindle distance is grossly different than the stated 212mm, it's an easy task to measure that distance on the Pro-Ject 'arm. I get ~212mm with an aluminum 9 tonearm installed on a (Pro-Ject) mmf-7 turntable.
If Wilson667 takes a few quick measurements it may eliminate a couple of the obvious variables.
Tom
