Tracking error distortion audibility

Dear Axelwahl, the pivot bearing to spindle distance does NOT determine were your zero-error points are located. Again - see the Graham alignment tool with 2 options to adjust to either Baerwald or Loefgren - the zero-errors are on different points on the arc, but the spindle-bearing pivot distance is of course the very same on both, as the base of the Graham is not moved, but the adjustment takes place at the headshell ONLY.
I guess the point is clear now - isn't it?

Dear Axelwahl, good to learn your mounting distance is fine. If you had checked that earlier, we could have spared some time and space here...
Anyway - if you still have inner groove distortion when the tonearm geometry itself is fine, then this can be related to several points:

a) lateral azimuth of the cartridge/stylus
b) horizontal azimuth of the cartridge/stylus
c) antiskating
d) 2nd zero-error point already long passed when you reached the inner grooves (the SME uses an IEC-standard when calculating the zero-error-points. The 2nd point is pretty close to the 1st and in the inner grooves you are close to the maximum error - why this IEC-standard was used and favoured by SME and Ortofon was explained in the "Prices for Oldskool tonearms"-thread. It has to do with the new way to master and cut LPs in the early 1980ies.

a) and b) can hardly be altered in the SME V, but you can try - usually there is a small degree of free movement. Both do have direct impact of the position of the stylus contact area to the groove walls.
c) antiskating or skating force as the source of distortion will apply, when the distortion is pre-dominant in one channel only.

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 it’s 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 Ortofon’s 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

Dear Axelwahl, this way this is leading nowhere in an endless circle.
It would really make sense if you browse through Google and download the original papers by Baerwald and Loefgren about tonearm geometry and the complex interrelations. Reading them will answer 98% of all your questions and will set the whole theme in the right context.
Alternatively ou may send me a direct email (via Audiogon - just click on my alias dertonarm ) with your telephone number and I will call you up and describe the point in both our mother language. So far you still do missunderstand a few points in tonearm set-up and I will gladly clarify them in a short telephone call.
Greetings from a lakeside with view to the northern Alps (Zugspitze),
dertonarm

Hallo Herr Dr. Tonearm,
now this is getting somewhere, very good!
This pivot / spindle distance actually only came about because of our protracted discourse, and me having it measured, no effort lost, methinks.
Also, some bystanders may profit, all very beneficial, no?

That IEC-standard got pretty well lost in the general 'shrapnel' flying about in the other thread -- at least for me not having been into it earlier.

a)I have addressed, but as you confirm and mentioned, setting it is VERY marginal with the last resort to bore open the mounting holes of the SME arm. Something that I'm not too crazy on doing since the PW cart is not THAT much out of true --- yet it definitely is and previous (new) Ortofon Jubilee had the same issue. (Sent back 3 times, etc. etc.)

b) don't know if that is VTA, please explain to correlate...

c) since it's on-the-fly, easy to test with the SME, tried and found innocent. The distortion is actually ONLY during high energy passages soprano blasting, tenors also at full tilt, sibilants included, as well as higher pitch (mostly) instruments e.g. ff full orchestra violins and sundry crescendos.

d) +++ 2nd zero-error point already long passed when you reached the inner grooves (the SME uses an IEC-standard when calculating the zero-error-points. The 2nd point is pretty close to the 1st and in the inner grooves you are close to the maximum error
+++
I'm confident you got that standard sussed, and it would explain exactly what's going on then. Now, how far are these ICE null-points apart, be VERY interesting to know?!

++++ - why this IEC-standard was used and favoured by SME and Ortofon was explained in the "Prices for Oldskool tonearms"-thread. It has to do with the new way to master and cut LPs in the early 1980ies.
++++
I have my take, which may repeat what's been said on the other thread?
DG by example had decided to leave a LOT more dead wax to the end (early 80s, yes) to improve on the very IGD issue. That being so, it would explain why null-point 1. and 2. got moved closer together, wouldn't it?
Some GREAT ideas don't always do so good like e.g. RCA's Microgroove (...virus).

Now, what about Linn I ask?
Also gone IEC-standard?
Would be interesting to know (I hope you don't need to repeat all of this...)

Lastly if you want to drop the IEC-standard it will of course need to re-think / set all, by NOT going with the manufacturers supplied tools. Not a very cheerful thought, I say.

Greetings,
Axel