I agree on the importance of correct azimuth. Critical azimuth setting IMO is more important than critical horizontal tracking setting which occupies so much of our posts and energies, it seems.
Just a few comments. I begin with trying to set the cartridge level by viewing its reflection in a playing recording and making it parallel to the cartridge. I use an Audio Technica cartridge, which I think is more likely to have the cantilever and stylus placed symmetrically than smaller volume producers. If I had a more hand made device I would try hard as I can to see the stylus vertically in the groove. But this is only a starting point.
The final setting must, I think, be by ear. I would not use a mono recording; I would use a stereo recording with the biggest sound stage in my collection, classical preferably. I would make very small adjustment with the aim of maximizing soundstage for that would maximize separation which is the object of correct azimuth.
For those that use VPI unipivot arms I highly recommend the second pivot option. Even if it accomplished nothing else, and it does, it makes setting azimuth crazy easy. You just dial it in. I was VERY pleasantly surprised at what a small difference in azimuth can make in enlarging the soundstage. You can't do it on the fly, but it works out easily enough.
Just a few comments. I begin with trying to set the cartridge level by viewing its reflection in a playing recording and making it parallel to the cartridge. I use an Audio Technica cartridge, which I think is more likely to have the cantilever and stylus placed symmetrically than smaller volume producers. If I had a more hand made device I would try hard as I can to see the stylus vertically in the groove. But this is only a starting point.
The final setting must, I think, be by ear. I would not use a mono recording; I would use a stereo recording with the biggest sound stage in my collection, classical preferably. I would make very small adjustment with the aim of maximizing soundstage for that would maximize separation which is the object of correct azimuth.
For those that use VPI unipivot arms I highly recommend the second pivot option. Even if it accomplished nothing else, and it does, it makes setting azimuth crazy easy. You just dial it in. I was VERY pleasantly surprised at what a small difference in azimuth can make in enlarging the soundstage. You can't do it on the fly, but it works out easily enough.