This is why it’s good to have a single-point universal like the GeoDisc in your toolkit. Also I use the SMARTractor, another single-point true universal (with multiple curves to choose from) which is definitely more precise, but also much more expensive. And I’ve used a Mint LP (2-point) to good effect, but it’s frustrating to have to buy a new one for EACH setup (yes you really have to).
The simple GeoDisc should work quite well with your unusual tonearm, because the center pivot point is so easy to visually sight - when you can’t clearly "see" the pivot point, the GeoDisc doesn’t work very well. The GeoDisc is based on the Loefgren A IEC curve (i.e. Baerwald), which is quite common and generally works well. Your P2S distance should ideally be set based on the tonearm maker’s recommendation, but if it’s a little off in reality, a true universal like the GeoDisc or SMARTractor will compensate for that (as long as you have enough leeway in your headshell slots), whereas the Mint LP will give you an increasingly erroneous result as you stray further from what the Yip thought the P2S should be. With a Universal - if you find yourself "short" on the headshell slot length (towards the front end of the shell) then the P2S distance is probably too big, and vice-versa.
In theory the MintLP for a specific setup will be more precise than even a SMARTractor (and I must admit the Mint has FAR better lines for cantilever alignment), but in reality this advantage will often be negated by P2S distance not being in EXACT agreement (again, unlike a universal, the Mint will not adjust for discrepancies here). I don't think it's uncommon for the P2S distance to be off by 1mm (or more) from where you requested the holes drilled into a blank armboard - maybe with a fixed ecosystem like a Rega you can be more confident in its published P2S distance. And the back-and-forth iterations between the two alignment points is a bit more time consuming, and can be a tad frustrating at first.
The simple GeoDisc should work quite well with your unusual tonearm, because the center pivot point is so easy to visually sight - when you can’t clearly "see" the pivot point, the GeoDisc doesn’t work very well. The GeoDisc is based on the Loefgren A IEC curve (i.e. Baerwald), which is quite common and generally works well. Your P2S distance should ideally be set based on the tonearm maker’s recommendation, but if it’s a little off in reality, a true universal like the GeoDisc or SMARTractor will compensate for that (as long as you have enough leeway in your headshell slots), whereas the Mint LP will give you an increasingly erroneous result as you stray further from what the Yip thought the P2S should be. With a Universal - if you find yourself "short" on the headshell slot length (towards the front end of the shell) then the P2S distance is probably too big, and vice-versa.
In theory the MintLP for a specific setup will be more precise than even a SMARTractor (and I must admit the Mint has FAR better lines for cantilever alignment), but in reality this advantage will often be negated by P2S distance not being in EXACT agreement (again, unlike a universal, the Mint will not adjust for discrepancies here). I don't think it's uncommon for the P2S distance to be off by 1mm (or more) from where you requested the holes drilled into a blank armboard - maybe with a fixed ecosystem like a Rega you can be more confident in its published P2S distance. And the back-and-forth iterations between the two alignment points is a bit more time consuming, and can be a tad frustrating at first.
