How important is Cartridge Overhang? Need help

Hi, Wilson667; hopefully things all work out with your Mint protractor. What is the distance from the vertical tone arm pivot to the center of the headshell slots? You should get something around 220-221mm if the effective length is correct at 230mm. (220.5mm + 9.5mm holes-to-stylus = 230mm)

I measured the distance on my Pro-Ject 9 aluminum 'arm and the center of the headshell slots is just over 220mm from the pivot, which is correct for a typical 9.5mm mounting hole-to-stylus distance. It could easily accomodate the 8.5mm distance of the HMC-20.

Tom

As many of you know, but perhaps the OP does not, if the actual spindle to pivot distance on the table is not to spec, and if the Mint was built based on manufacturer's spec (rather than measured pivot to spindle), then the Mint will not be "correct". Since the stylus to pivot distance is "variable" in an arm w cart mounting slots, it really does not tell us all that much, unless there is a gross mismatch.

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

Hi Tketcham
just wanted to add some info in hopes of finding a solution.All the measurements I have made on the Pro-ject 9C tonearm (carbon arm with attached aluminum head shell) are as follows:

Pivot to spindle, 212 mm
pivot to tip of head shell, 235mm
pivot to center of head shell slots, 228mm
cartridge mounting hole to stylus tip, 8.5mm

Dear Wilson667: Due that the pivot to spindle distance is fixed: 212mm then the pivot to to stylus tip must be ( Baerwald. ) 230mm and not 235mm as you have right now.

This means that you need to go back/rearward with the cartridge by 5mm and offset angle: 24°. In this way you will be right on target.

Regards and enjoy the music,
Raul.