How a record player works

Vibrations from sound waves can produce movement in a needle attached to a diaphragm. If this needle is placed on a rotating surface a groove can be cut. The principle behind the record player is that another needle can then be placed in this cut and as the record is rotated tiny indentations in the walls of the grooves move the needle. The needle is connected to a tiny magnet that moves through a small coil. As every GCSE student knows, magnets moving through wires produce current. This current can then be sent to the amplifier which can then reproduce the original sound.


A more detailed description can be found here.
For information on the synthetic diamonds used in the record player cartridge see the industrial diamond page.


Front Chemistry History How it works Make your own Links copyright Daniel Cressey 2001