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Offset Angle on VPI Classic Tonearm

Out of curiosity, is it everyone else's experience who owns a VPI Classic with the Classic tonearm that they have to twist the cartridge out to achieve correct offset angle? I have a Lyra Delos, and I've used the VPI jig, the Mint, and Ken Willis' Accutrack that allows setting up with all four geometries (Baerwald, Loefren, VPI, and Stevenson), and they all require a healthy twist of the Delos in the headshell to achieve a proper offset angle. I understand that having to twist the cartridge in the headshell when aligning it to a specific geometry is nothing new or controversial, but I am puzzled why make a tonearm that does not comply symmetrically even with the proprietary jig designed specifically for it. I can't imagine a cartridge that would not require twisting to be aligned correctly, but am perhaps wrong?
actusreus
actusreus OP
733 posts
 
Captain_winters,

As you're looking from above, you can see that front of the cartridge's body is not parallel to the front of the headshell's face (my Delos also extends beyond the headshell). The Delos also has a symmetrical hole drilled through it for a different mount and you can see that the hole is not aligned with the symmetrical line notched through the front of the headshell. To describe it differently, you can see the mounting screws are not aligned symmetrically in the headshell slots. I had to twist the cartridge out to get the correct offset angle on the protractors (to have it parallel to the lines on the arc when the stylus rests on the null points). The cartridge appears perfect. Any ideas why the twist with mine is necessary?
stringreen's avatar
stringreen
6,468 posts
 
I have a Benz LPS and aligned it with the MINT....it looks absolutely square to me....overhangs the headshell a bit.
brf
1,715 posts
 
Dyan xx2-mk2 is square in the head shell with 1/8 inch overhang from the head shell
Koetsu Black has a very very slight twist and with 1/8 inch overhang from the head shell.
To the uniformed eye, both cartridges look square in the head shell.
actusreus OP
733 posts
 
Interesting. The twist is required for every alignment tool I've tried. This tells me the cartridge must have some sort of an asymmetric quality to it; I guess an almost imperceptible cantilever asymmetry. It'd be interesting to hear from other Delos owners.
captain_winters
133 posts
 
Actusreus
I suggest ensuring that you have zero azimuth when you are aligning the cantilever with the MINTLP.  If you have azimuth other than zero, either cartridge tilted to the inner or outer groove, you might be twisting the cartridge to compensate for a visual artifact of the azimuth.  I use the MINLP surface, and the azimuth rod, and an accurate ruler to ensure I have equal distance from the rod to the MINTLP glass before I align the cantilever.  Both of my cartridges stick out a little from the front of the head shell, but for all practical purposes the cartridge is parallel to the face and the screws are also in the same place in the slots of the headshell.
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