Reviewer: Pierre Lurné - TNT France
Reviewed: September, 2020
I promised this article would be about tone arms, but first, a summary of where we are and what lessons can be drawn from this reality? When one buys a cartridge, the tracking error is already in the box, because nothing done by man is perfect. Any product, of any kind, suffers from “mechanical or manufacture tolerances or margins” which affect the making and the assembling precision and, consequently, there is absolutely no way of knowing the size of the inherent tracking error of the cartridge you have just bought.
Large or small, who knows? To the left or the right side, who knows? Then, your own set up of the cartridge in the arm head-shell, will not be perfect again, will add, or subtract, to the value, who knows? (See details on the previous article). In addition, tracking angle concerns the horizontal plane only and, indeed, this usual and inevitable lack of precision is at work in the two other planes: the azimuth error in the lateral plane and the VTA/SRA error in the vertical plane. Manufacturers do their best in spite of the problems. Mainly thanks to magnifying optical means, microscopes, profile projectors, time, etc. Similarly, hi-fi enthusiasts try to do their best too with their protractor in hand, but they must keep in mind that this adjustment is nothing but a very rough guide. Without the relevant measurement instruments, the only solution is to “twist” one's cartridge a tiny bit and after several trials a “sweet point” emerges. Relax, it is rather easy to do!
The tracking angle problem is a drawback of the pivoting arms. Tangential arms are free of it by principle. Still, if one buys a tangential arm to get rid of the tracking error, he is going the wrong way and wasting time because it's already inherent in the cartridge, and even larger than the usual smaller one made at the set up. Thence, again, “twisting” one's cartridge in search of the “sweet point” can help. In other words: when any audiophile in the world is setting up a cartridge, he helps himself with a protractor and he expects a very small remaining tracking error of, let's say, 1 or 2 degrees of angle. If he uses a tangential arm, he expects almost zero degrees. Both situations are totally wrong as the cartridge's own tracking error is much larger and has been totally passed over, in silence, for decades (!?). Let's take the example of a cartridge affected by a 4° tracking error, an average value depending on your budget and on your luck on the day you bought it (more details here). After setting up on a pivoting arm, the total error will range from around 4+1 = 5°, if the two errors add and on the same side; or 4–1 = 3°, if one error is on the left and the other on the right they subtract. Comparatively, on a tangential arm, the tracking error will remain more or less at 4°.
Don't haggle over the numbers, focus on the principle. Whatever the arm used with your cartridge, pivoting or tangential, the tracking error will be roughly similar! No matter the type of arm used! A Revolution in our Little Analogue World! Statistically speaking, the tangential arm could have a small advantage over the pivoting arm. In practice things are different because nobody uses an “average cartridge-arm combo”, but only his own particular one with its own unknown flaws, large or small.
The next article will be entitled: The Naked Truth (TNT) about Air Bearing Tone Arms.
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