Tracking error distortion audibility

Dear Axelwahl, the TT's spindle to the tonearms pivot bearing point is NEVER variable in a pivot tonearm. It is the ONE single FIXED foundation of a given tonearms geometry. The distance of the tonearms pivot point to the center of the LP (= spindle of TT's bearing ) is NOT variable. The SME sliding mount is not meant to "variate" the mounting distnace nor to compensate for the fixed cartridge mounting holes. The SME V has a fixed mounting distance of 215.35 mm (SME does give this value in such detail because it is paramount for the whole tonearm geometry....).
Not taking this point as serious as it is means to skip the whole geometry alltogether and results in poor sonic performance and high distortion.

Please see here:
http://www.sme.ltd.uk/content/Series-V-1330.shtml

Woopsy,
I might get something VERY wrong here. Now PLEASE how can it be as you say... if I move the tone-arm post (containing the pivot bearing) back or forth -- it should be STILL the same distance to the centre bearing / spindle??
What is truely fixed (SME) is the distance from the mounting holes to the pivot bearing. Since there is no standart from mounting holes to stylus tip (usually ~ 9mm) the arm post in the SME design can slide back and forth to adjust for correct overhang.
This means the arm-post (containing the pivoy bearing, yes?) will change its distance to the record main-bearing centre pin, its unavoidable else there'd be NO overhang adjustment possible.
The only way to adjust overhang with a FIXED pivot to centre pin distance is to have oblong head-shell holes and NO SME head-shell has, hence the arm-post slide system.
Maybe we are not talking about the same measuremen(s)?
Axel

Dear Axel, we do talk about the same thing.
However - there is a huge missinterpretation by several SME V owners.

On the whole sliding distance of the SME mount - some 25 - 40 mm - there is ONLY ONE POINT where the spindle - pivot bearing distance (=mounting distance) is exactly the 215.35 mm SME does specify.
The distance is always the same on a circle around a given fixed point (here: the spindle). The SME slide does not feature a circle segment, but a linear one.
I guess the point is clear now - isn't it??
The SME-mount was introduced in the 1950ies to allow precise alignment of the mounting distance even when the drilling of the wooden armboard was inprecise. The fact that the SME V does feature fixed cartridge mounting holes have been critiszed from the day of its introduction.
It is simply a big mistake in its design. If the horizontal distance mounting holes to stylus on all cartridges would be the same (as it should, but is not...) , then SME would be right. But in real world, the SME does not allow adjustment of overhang........ with a given cartridge you either get it right by simple luck - or you doesn't.
You can not adjust it.
Unfortunately cartridge designers do not stricly design there cartridges with a standardized distance mounting holes to stylus.

Again - yes, there is no overhang adjustment possible with the SME V......
Sorry - SME's fault.....
I know a few SME V owners who do indeed have modified their SME V so that now they do feature oblonged holes to mount the cartridge.
They can adjust the overhang now.
With a stock SME V you simply CANNOT adjust the overhang.
If you try by using the SME slide, your whole geometry goes nowehere.
Thus the SME V does limit your selection of useable cartridges quite a bit......

Holy moly, you are dead serious in what you are saying as I can read ---- BUT something does not gel at all.

1) SME adds a overhang template, with a machined bushing for the V! (it goes over the centre pin). Then you put your stylus into a tiny prick-holed template (marked by a cross) and adjust the overhang so that the arm geometry (arm is tapered, yes) aligns visually, from above with the template! There is a lengthy section in the manual just dealing with that and exactly how to do it (and how not to do it). Also the is a special key tool to do the sliding bit (nothing like hand moving here). All that just to get this micron exact point -- with NO gauge to support your idea? Sound pretty far out, now doesn't it?

2) There'd be NO means, other than some funky optical measuring equipment, maybe the latest for a tool-shop, that would be able to set the arm as you suggest.

3) Since there are precision holes (for cap screws) drilled and tapped into the ALU arm-board, they could be just fine and no pivot-post movement mechanism needed, just some oblong holes, right?

4) There seems to be a MAJOR discrepancy here with some other expert Forum members that maintain that the pivot to centre-pin distance is NOT of the ULTIMATE importance as I hear it from you.

5) If it really was, why would SME for the last 50 years maintain a pivot post slide on the "best tone arm in the world" (their words, not mine) It written on the box, believe it or not.

6) So, I guess I hear your argument loud and clear, but SME can't be the one to support it, rightly or wrongly... And I do NOT say: you don't have a point.

I got to digest that bit! Do some geometry to see if your argument is valid, though.

It may just turn out as yet another funky argument, like all the differing anti-skating, and dynamic VTF stuff.

I'm baffled, but thank you for sharing,
Axel