Ball bearings are very popular in tonearm design and are used quite often. Today, high-tech manufacturing processes allow bearings with very low tolerances. The bearings in the Schick arms have a 0 µm positive tolerance and 7 µm negative tolerance. This means that there may only be a maximum of 7 µm small ‘holes’ in each ball respectively to its race. However, there are many balls in the bearing, so the probability that several deviations form this 7 µm clearance at the same time is very low. This principle results in a connection that is practically free of play. Leaving enough ‘air’ of course to rotate freely.
This low tolerance has other properties that are advantageous when building the tonearm: Low running noise. Running noises are undesirable. In the form of resonances, they also contribute to the loss of information. The low tolerance of the polished raceways and balls as well as a synthetic lubricant ensure the lowest possible running noise. It is possible to buy bearings that look very similar for a small price, but the low quality can be heard directly. When turned close to the ear, cheap bearings generate noise. You can hear the metallic crunching noises of a brand-new, perfect bearings! Nothing you want in the sound of your turntable system.
For example, turn the vertical axisof an old tonearm and you’ll know what I’m talking about.
Low tolerance and a smooth surface have another advantage. A low breakaway torque.
The mechanical force to set the bearing in motion at all is very low, so the pickup can better. The extremely smooth surface also keeps rolling friction very low, not least thanks to the special synthetic lubricant. A normal ball bearing grease would act like glue here.
One more word about durability. These bearings are specified for extremely high speeds, something that is not found in tonearm life, but this guarantees an extremely long life of several decades.
Apart from the movable axes of the tonearm, the choice of material also plays an important role. Metal is a good resonator, which is bad at first. But metal parts that are mechanically connected to each other hardly resonate anymore. In Schick tonearms, the headshell construction takes over this function, among other things. The contact area between the arm and the headshell plug very effectively reduces the resonance. The same goes for the axis through the arm and the counterweight. All elements are connected to one another to reduce resonance.
Special attention was paid to the damping of the tonearm tube. Here 3 different materials in 9 sections are used to optimize the resonance behavior. Optimal does not mean absolute ‘dead’ (overdamping), but rather using it in the right place, in the right amount.