This is an old thread, but it caught my attention
because I have been trying to refine the alignment
geometry on my VPI 12.7 tonearm (mounted on a VPI Classic 3 TT). I recently overcame my reluctance
to buy a Feickert protractor, and since I already
own a Fozgometer it didn't make sense to cavil
over a few more dollars to do the job right. I
spent about an hour tinkering with the protractor,
and the spindle-to-pivot distance proved to be 297
mm. That's 1 mm shorter than the 298-299 mm range
stated by VPI, and roughly 5mm shorter than the
302 mm measurement mentioned in this thread. I
have no explanation for this anomaly, except
perhaps that VPI was a hair off mounting the
tonearm to the plinth. After I finished aligning
the cartridge, I used the Fozgometer to adjust the
azimuth, and eventually got the signal strength of
both channels to within 0.5 db of each other. Good
enough, said I.
because I have been trying to refine the alignment
geometry on my VPI 12.7 tonearm (mounted on a VPI Classic 3 TT). I recently overcame my reluctance
to buy a Feickert protractor, and since I already
own a Fozgometer it didn't make sense to cavil
over a few more dollars to do the job right. I
spent about an hour tinkering with the protractor,
and the spindle-to-pivot distance proved to be 297
mm. That's 1 mm shorter than the 298-299 mm range
stated by VPI, and roughly 5mm shorter than the
302 mm measurement mentioned in this thread. I
have no explanation for this anomaly, except
perhaps that VPI was a hair off mounting the
tonearm to the plinth. After I finished aligning
the cartridge, I used the Fozgometer to adjust the
azimuth, and eventually got the signal strength of
both channels to within 0.5 db of each other. Good
enough, said I.