Hallo Herr Tonearm :-) and who ever is still with us
As I said, my tonearm pivot to spindle centre is to SME spec. as it turns out, (with my current cart, Per Windfeld).
I thought THAT was the salient point of YOUR departure on the DEFINITIVE- tracking error as a result, if this measurement is out of spec.
So now as this is right on spec, I try to understand why this should yet also be a problem?
Baerwald or Loefgren have THEIR best interpretation about where the null-points aught to be, Linn has theirs, SME theirs and so on. There is no FINAL and ONLY position where these null-points aught to be, else e.g. Linn and SME would have it ALL wrong the last 50 years --- is what I understand you try to relate, no?
Every 'template maestro' has his own sweet intuition about how to get there, so as to have the least distortion as a result. No problem with that at all, but as always more than one way leads to Rom (and many of course do not, also true).
I just think, if your first point is not the case here (spindle / pivot right on spec. in this here situation) why question the manufacturers 'preferred' set-up, and go on about other set-ups?
The exact arm-pivot to spindle with an e.g. Linn 9" arm is different to SME 9" arm and so is their resulting overhang and therefore their exact set-up. I guess you only let me off if I go with some set-up other than SME's, no? :-)
There is one still relevant item that was not even mentioned this far, that at both null-points, where ever they are picked to be, the cart's cantilever aught to be as close to 90 deg., as can possible be, in order to have at least at these two points 0 deg. tangential tracking error.
It seems to me, that it here where the SME (and Linn) arm can cause a problem with a cart's skewed cantileve. The SME arms (just as Linn's) have next to NO play to allow for the cart's cantilever skewness to be compensated, true.
With older cart designs its less of an issue, since they have no threaded mounting holes but need rather a longer screw and nut for fastening. This allowed (allows) for a slightly bigger margin for twisting the cart body to get the cantilever (rather than cart body only) aligned. And I would agree further, that the method used by Graham seems just about the best to achieve that also!
So not all is lost.
My last point: I do question greatly whether e.g. Graham arms (any other arm) are mounted, spindle / pivot, to the 100th of a millimetre correct! Never in all your live!
And it was THIS distance's absolute need for TOTAL correctness that stared this dialogue Egyptian geometry and all so at least my take. I might have missed something though.
SME also Linn assume that the cantilevers of the carts mounted are not out of true. Experience shows that this is of course not so, but it is a question of the degree of skewness relative to the cart body, with 1-2 deg. seeming the acceptable tolerance, so my understanding by Ortofons techies.
Now I may only wish that or discourse will be of some edification not just to the two of us :-)
Mit bestem Gruss,
Axel
As I said, my tonearm pivot to spindle centre is to SME spec. as it turns out, (with my current cart, Per Windfeld).
I thought THAT was the salient point of YOUR departure on the DEFINITIVE- tracking error as a result, if this measurement is out of spec.
So now as this is right on spec, I try to understand why this should yet also be a problem?
Baerwald or Loefgren have THEIR best interpretation about where the null-points aught to be, Linn has theirs, SME theirs and so on. There is no FINAL and ONLY position where these null-points aught to be, else e.g. Linn and SME would have it ALL wrong the last 50 years --- is what I understand you try to relate, no?
Every 'template maestro' has his own sweet intuition about how to get there, so as to have the least distortion as a result. No problem with that at all, but as always more than one way leads to Rom (and many of course do not, also true).
I just think, if your first point is not the case here (spindle / pivot right on spec. in this here situation) why question the manufacturers 'preferred' set-up, and go on about other set-ups?
The exact arm-pivot to spindle with an e.g. Linn 9" arm is different to SME 9" arm and so is their resulting overhang and therefore their exact set-up. I guess you only let me off if I go with some set-up other than SME's, no? :-)
There is one still relevant item that was not even mentioned this far, that at both null-points, where ever they are picked to be, the cart's cantilever aught to be as close to 90 deg., as can possible be, in order to have at least at these two points 0 deg. tangential tracking error.
It seems to me, that it here where the SME (and Linn) arm can cause a problem with a cart's skewed cantileve. The SME arms (just as Linn's) have next to NO play to allow for the cart's cantilever skewness to be compensated, true.
With older cart designs its less of an issue, since they have no threaded mounting holes but need rather a longer screw and nut for fastening. This allowed (allows) for a slightly bigger margin for twisting the cart body to get the cantilever (rather than cart body only) aligned. And I would agree further, that the method used by Graham seems just about the best to achieve that also!
So not all is lost.
My last point: I do question greatly whether e.g. Graham arms (any other arm) are mounted, spindle / pivot, to the 100th of a millimetre correct! Never in all your live!
And it was THIS distance's absolute need for TOTAL correctness that stared this dialogue Egyptian geometry and all so at least my take. I might have missed something though.
SME also Linn assume that the cantilevers of the carts mounted are not out of true. Experience shows that this is of course not so, but it is a question of the degree of skewness relative to the cart body, with 1-2 deg. seeming the acceptable tolerance, so my understanding by Ortofons techies.
Now I may only wish that or discourse will be of some edification not just to the two of us :-)
Mit bestem Gruss,
Axel