The Dawn of a New Era The modern phonograph cartridge uses magnetic flux to produce a voltage corresponding to the groove information. This is accomplished by attaching a magnet or a coil to the cantilever that is moved by the stylus placed in the groove. The voltage output is produced by movement (velocity) of the coil or magnet cuttings the magnetic lines of force. There have been several other approaches to the solution of producing voltage from movement of the stylus/cantilever, the Win FET 10, Stax CPY Toshiba C-100P. I have experience with all of these. The Toshiba C-100P is the forerunner (about 40 years ago) to the DS cartridge. This type of cartridge uses a light source focused on a photo diode. The light source reaching the photo diode is varied by the movement of shading plates attached to the cantilever moved by the stylus contact with the record groove. Thus the voltage output (amplitude) produced by the cartridge is in step with the stylus to groove movement. The benefits from this are about 10 times less mass attached to the cantilever, linear out put and output starting at DC. The main difference is the sound.The most real reproduction of music I have listened to in my 50 years of association with vinyl records and the audio bussiness