Setting tonearm angle?

Why would the azimuth change when you adjust the VTA? The two are set in two different planes. The SRA and overhang, sure, but not the azimuth.

I have an on-the-fly VTA adjuster on my Dynavector 501 arm (Pete Riggle), and I have several cartridges to adjust VTA on. They vary greatly in proper adjustment, from the Dynavector XX2MKII, two different Actex LPM, and Zu Denon 103R.

Having the Riggle VTA adjuster helps considerably in quickly setting VTA to optimum height. The point being, after overhang and alignment has been set for each cartridge, in their individual headshells, I have noticed no loss in sound quality due to improper overhang, just the improvement gained by proper VTA.

In other words, I haven't noticed the necessity of adjusting overhang as VTA is adjusted. I may be missing something, maybe the fact the sub-arm is so short that when the main arm is raised, the changes in VTA may occur with less variation in height of the main arm.

Further discussion would be welcome, as I am still learning about how to get the most out of my analog rig. I think I would go nuts if overhang had to be reset each time. Makes a good case for multiple tonearms/turntables.

Best regards,
Dan

agree with Islandmandan...almost all cartridges need some sort of angle not the straight line as the tonearms is set in the first time...also double check the tracking force again with the Digital Tracking Force Gauge after you set the VTA.

I agree that VTA shouldn't affect the azimuth, in theory. It does in this case. Tracking force goes off a lot too.
The VPI arm with it's free moving wobbly pivot system is a bit weird to work with. Seems to be a great system though.
Is this "unipivot" systen used in other TT designs?

When leveling the tonearm parallel to the record surface I think it makes more sense to concentrate on the cartridge rather than the tonearm, especially if the tonearm tube is tapered.

The front of my cartridge is perpendicular to it's top, therefore if I can get the front perpendicular to the record surface, the tonearm will be level.

I made a reference block by squaring up a piece of oak with 90 degree edges on the table saw and jointer. From that flat board with square edges I cross-cut 3" long blocks, knowing the tops and ends were perpendicular to each other.

With the stylus set to it's normal tracking force and at rest on a non spinning 180gm disc , I adjusted the tonearm height until the face of the cartridge was flat against the perpendicular edge of my reference board. My tonearm and cartridge assembly were now more or less parallel to the record surface.

My tonearm has no scale or markings to measure the tonearm height. You loosen a setscrew, raise or lower the post and pray for the best as you re-tighten the set screw. I used playing cards as shims between the bottom of the spindle and the base varying the height by varying the number of cards.

I can now measurably change the VTA and judge the sonic effect for myself by adding or subtracting playing card shims. Now it is possible to adjust the VTA by ear simply by adding or removing shims.

Azimuth adjustment is also possible using thin paper shims between the headshell and the cartridge.