DT, I thought it was someone else who actually suggested that azimuth adjustment is a desirable feature, BECAUSE of possible problems related to the spatial location of the armboard with respect to the platter. We don't disagree on this.
However, I do get a sense of security with tonearms that provide for azimuth adjustment vs those that do not. Unfortunately, the sad fact is that most tonearms that offer the feature also change VTA along with azimuth, because to change azimuth, they rotate the arm tube near the pivot, not taking into account the offset angle of the headshell. Best way to do it is right at the headshell, so only the headshell rotates and only in the vertical plane of the stylus tip. Only Reed does it that way, or some detachable headshells offer it as well.
Actually, I was wrong in my geometrical analysis; the situation is even worse than I wrote, if one were to try to correct for armboard/platter disorientation using azimuth. At the very best, you could only restore the proper relationship (platter plane parallel to armboard) at one single point across the entire surface of an LP. And that's assuming the error was within the arc described.
However, I do get a sense of security with tonearms that provide for azimuth adjustment vs those that do not. Unfortunately, the sad fact is that most tonearms that offer the feature also change VTA along with azimuth, because to change azimuth, they rotate the arm tube near the pivot, not taking into account the offset angle of the headshell. Best way to do it is right at the headshell, so only the headshell rotates and only in the vertical plane of the stylus tip. Only Reed does it that way, or some detachable headshells offer it as well.
Actually, I was wrong in my geometrical analysis; the situation is even worse than I wrote, if one were to try to correct for armboard/platter disorientation using azimuth. At the very best, you could only restore the proper relationship (platter plane parallel to armboard) at one single point across the entire surface of an LP. And that's assuming the error was within the arc described.
