2. analog
  3. 157961-1975

I finally get it!

I had a long  discourse with VPI after I bought my new Classic 3 Sig SE years ago. The subject was that the S2P distance was off. After over one year of trying to get this resolved, I still received my tt back with this distance 1 mm (long).

I always wondered why there was no forthcoming measurement of the S2P distance. After all, VPI is know to have customers DIY their own tts, based on VPI's own products.

So, VPI offers their set-up jig with new tts. They don't offer any specific measurements for S2P. Someone had to ask on their forums in order to find out. Why?

I now know why. Because, their manufacturing was/is not very precise. So, if their S2P distance was off when the tt left their shop, their own jig (provided) would still keep the S2P distance in a (good enough) range. 

Nice try/trick.
128x128slaw

Showing 2 responses by phoenixengr

phoenixengr's avatar
phoenixengr
92 posts
 
slaw-
VPI has their metal work done by MDI, a very competent machine shop in NJ, so I don't think it is machining tolerances.  VPI assembles the parts, made by other companies for them, so it may be an assembly error.

From what I can tell, part of the problem is HW never put much importance on S2P measurements:

https://www.audioasylum.com/cgi/t.mpl?f=vinyl&m=1122027


This is a strange position to take for a turntable mfr, but  it might explain a lot.  IMHO, HW doesn't really understand tonearm geometry.  He has touted a 14" tonearm with no offset and claims it has no skating force and two null points; both assertions are incorrect (the math to prove this is trivial).  He posted that he discovered the benefits of no headshell offset by twisting the cartridge on an overhung tonearm with offset until the cantilever was aligned with the arm tube and the sound was "jaw-dropping".  I think the only thing that would be jaw-dropping would be the distortion as the tracking error would be ~17° and the distortion would be approaching 20%.
phoenixengr's avatar
phoenixengr
92 posts
 
A 1mm error in effective length implies a 0.1mm difference in overhang and a 0.1 deg difference in cartridge alignment. This should not be a drama. Read the articles.


@olddears

Where are you coming up with your numbers? A 1 mm difference in effective length (or S2P distance) will create a 1 mm difference in overhang and 0.87° tracking error at the null points and 1.47° tracking error between the nulls. Not huge, but an order of magnitude higher than you are quoting and completely unnecessary.

What other mfrs are as sloppy about this as VPI?
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