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© Pro-Ject Audio Systems · Pro-Ject Align it PRO · Revision 2022.10.07
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From the beginning, the tracking error has a positive value, but between null-points is negative and after the
inner null-point positive. That is why our formula mentioned above counts with the absolute value of tracking
error. The red curve represents distortion. The Baerwald geometry works universally and equally well for many
musical tastes. An excellent allrounder, which is why it is so popular.
Null-points explanation
During playback, the stylus follows an arc on the record surface. And only at two points is the stylus tangential
to the record grooves. The picture from vinylengine.com shows it exactly.
The arc path is purple in color. And on the arc lie two points where the green line (orthogonal to the axle of
the cartridge) intersects precisely the center of the record. These points are called null-points. We have zero
tracking error in these null points, resulting in zero distortion.
Other consequence of not correctly adjusted cartridge
If your cartridge is not aligned, there is a good chance that the cantilever will never be tangent to the groove
and that the angle between the two will take exaggerated values. This can cause a lot of distortion and
mechanical tension on the cantilever of your cartridge and the stylus itself and wear down the grooves of your
records.