Do you know your zenith error? Correct it!
Years ago, we were instructed to align our cartridge body at the protractor null points to achieve ideal alignment. Later, Wally Malewicz gave us the original WallyTractor and a way to improve upon this by aligning the cantilever at the null points while also removing parallax error.
However, we haven't had a way to align that which REALLY matters when setting your stylus/cantilever assembly for ideal horizontal alignment: the contact facets of the stylus that read the groove walls.
Your cartridge is in perfect alignment on the horizontal plane when a line drawn between the two contact facets form a straight line pointing at the center of the record. This straight line SHOULD be perfectly perpendicular to the cantilever - which is MUCH easier for us to see and therefore align for optimum playback quality.
However, cartridge manufacturers often work with 2 to 3 degrees of tolerance with their stylus mount accuracy (though we have seen as much as 4.75 degrees off of perpendicularity with the cantilever.) This means that even though you aligned your cantilever perfectly at the null points, your stylus could be badly out of alignment - completely nullifying your best efforts to achieve minimum tracing distortion.
This zenith error (which, as a function of visual alignment is alternatively referred to as angular error) can cause you to experience quite audible tracing distortions without being aware of it. You are not likely to notice that the soundstage isn't as wide and deep as it should be. Nor will you notice the imaging isn't as pinpoint as it could be. If your stylus isn't properly oriented in the groove, dynamics will be muted, high-frequency extension dulled and the "suppleness" that vinyl playback is known for is just not what it could be if the zenith error were corrected for.
For now, the only way to measure your stylus zenith error is with very high quality microscopy like that which we use in our Cartridge Analysis Service. However, we are currently working on a method that would allow anyone to measure zenith error of their cartridges without microscopy.
The solution to MEASURE zenith error is coming in 2021!
The WallyZenith is for use when you already know what your stylus/cantilever zenith error is and wish to make a corrective alignment. It is possible, though not very practical, to use the WallyZenith as a measurement tool for zenith error. It may not be practical as it involves repeated listening and subjective assessment. WallyZenith is a corrective tool first and foremost.
In addition to offering the ability to align the stylus contact edges to be perfectly parallel with the record radius and thereby read the left and right channel grooves simultaneously, the WallyZenith allows the user to align for ideal cartridge azimuth BEFORE aligning the cantilever.
Using either the WallyReference (or the customized shim included with the WallyTools Cartridge Analysis service) to quickly and easily align azimuth followed by an alignment of the cantilever with the WallyZenith saves an enormous amount of time and hassle and ensures maximum playback optimization with the greatest accuracy and ease. See the calculator used to determine the visual angle required when zenith correction is performed when an azimuth angle is already present in the cartridge mount using the button below.