Stylus on LP record. Coloured scanning electron micrograph (SEM) of a stylus travelling through the grooves of a stereo vinyl record. The grooves are cut into a flat disc of polyvinyl chloride (PVC). The grooves vary with the intensity of the music: the straighter the groove the quieter the music, the wavier the groove the louder the music. Vibrations are picked up by the stylus and transduced by a moving-coil or moving-magnet cartridge into an electrical signal, which passes through an amplifier to be heard on loudspeakers. Magnification: x72 at 5x7cm size.