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Confusion on S2P distance for Classic Tonearm

PostPosted: Thu Oct 29, 2020 5:12 pm
by wyoboy51
I looked all over the forum but found inconsistent answers to this. I recently purchased a used Classic tonearm to go with my 10.5i tonearm both of which will be mounted on a custom turntable. I assume it's a Classic 1 arm since there are no other markings other than "Classic" on the headshell. I originally thought S2P distances were the same for both the 10.5i and the Classic. However, i discovered that the Classic arm is slightly longer (3mm) than the 10.5i and i started searching the web to make sure the 258mm S2P for the 10.5i also applied to the Classic arm. And then i found a post from Harry on the Vinyl Asylum website (January 6, 2010) in which Harry said, "The problem is the 10.5i is designed for 258mm spindle to male point mounting distance +/- 1 mm. The Classic is 262mm +/- 1mm mounting distance. They are not the same." There was no mention of whether the 15mm overhang is the same.
At the same time i've found several other posts on various sites on the web, including this one, that say they have the same 258mm S2P distance--leading to my confusion. Unfortunately i am unable to use the VPI alignment jig because the radius of my table's platter is 3mm larger than where the jig should fit over the platter edge--so i will use Feickert tools to measure and mount both tonearms. Just need to know if 262 is correct for the Classic arm--normally i would assume Harry to be the definitive authority on this but other moderators on the forum have said it's 258mm. Help !

Re: Confusion on S2P distance for Classic Tonearm

PostPosted: Fri Oct 30, 2020 10:07 am
by Brf
All JMW 10.5i, Classic series, Classic signatures, and 10-3D tonearms have a 258mm spindle to pivot distance. The only exceptions are the original JMW 10 and 10.5 tonearms which had a shorter effective length.

When using the single point Feickert alignment tool, the spindle to pivot is not crucial as long as your cartridge stylus can reach the protractor’s target. With arc protractors, you need to know the exact S2P distance and overhang to generate the correct arc for a specific tonearm.

Re: Confusion on S2P distance for Classic Tonearm

PostPosted: Fri Oct 30, 2020 11:55 am
by wyoboy51
Thanks for your response brf--one of the reasons i posted the question was because even though Harry said it was 262 i saw several posts by you saying it was 258--and i've seen enough of your posts to trust your advice as well. But, no offense, it still makes me wonder why Harry said it was designed to be 262... This almost seems to be confirmed by the fact that the arm is slightly longer than the 10.5i--If it really is 262 and i use 258, even if i can reach the outer Feickert target won't it be misaligned for the second, inner null point, geometry being what it is? On the other hand, what you say [about effective length i assume] makes sense -- although i'm wondering if using a different S2P just means the null points will move to somewhere else on the record--i remember seeing a calculator/spreadsheet on one of the sites where you could input whatever S2P and effective length you want and it would spit out where the null points are and tell you what the relative distortion would be at those points. I remember thinking at the time that the difference in distortion between null points at x and null points at y (where the difference was only a few mm) was so small i doubted anyone could tell the difference. It's certainly much easier for me to go with 258 here b/c that was what i had hoped in the beginning--to just be able to swap arms with no fuss other than VTA adjustment.

Re: Confusion on S2P distance for Classic Tonearm

PostPosted: Tue Nov 03, 2020 3:34 pm
by tujan
The P2S distance on my VPI Classic 3 turntable fitted with a Classic III tonearm measures 258 mm.

Re: Confusion on S2P distance for Classic Tonearm

PostPosted: Fri Nov 27, 2020 1:04 pm
by jllaudio
I have a Classic II. Is 258mm P2S still good for the Dr. Feickert?

Re: Confusion on S2P distance for Classic Tonearm

PostPosted: Fri Nov 27, 2020 3:28 pm
by Brf
jllaudio wrote:I have a Classic II. Is 258mm P2S still good for the Dr. Feickert?


Yes