Physics of the Turntable

Tracking System

Tracking system is the part of the turntable that connects the pickup system to the body and ensures that the pickup system stays in the grooves of a record.

Tracking Systems cosist of a tone arm, counter weight, and anti-skating device. The pickup system is connected to one end of the tone arm. Therefore, one of the most important functions of the tracking system is to apply a tracking force between the pickup system and the grooves of a record. Depending on the type of pickup system, the tracking force will be large or small. For a piezo-electric pickup system, the tracking force is relatively high because of the weight of the crystal. However, magnetic tracking systems are much lighter and need significantly less tracking force.

The counter weight attaches to the opposite end of the tone arm and acts to balance the weight of the pickup system. The counter weight is adjustable, which is a necessary feature in order to balance the tone arm so that just the right tracking force is applied. The tone arm needs to be relatively light so that it does not create sideways drag on the record as the grooves spiral inward. This is where the anti-skating device comes into play. This device attempts to offset the small, inward force applied to the record, so that the stylus itself is left with no net force on it in the horizontal direction.