There is only one way to extract the music and that is with a cartridge. A cartridge (Fig. 8.9) consists of three basic elements : the stylus, the cantilever, and the generating system.
1. The stylus : The stylus is the only part which makes contact with the record. A force must be exerted by the tonearm Fig. 8.10, to keep the stylus in the centre of the groove when the record is spinning.
Fig. 8.8 Movement of the stylus in a stereo groove (a) Right-hand channel modulated. (b) Left-hand channel modulated. (c) Both channels modulated equally and in phase. (d) Both channels modulated equally but in opposite phase.