The moving part of a speaker driver that generates sound through its movements which in turn create movement of air around the speaker. Diaphragms are typically cones or domes although they sometimes are in the form of metallic ribbons (planar-magnetic speakers) or thin, charged panels (electrostatic speakers). n dynamic speakers, which use cones and domes combined with a voice coil and stationary magnet, the diaphragm is connected to the voice coil, spider and suspension or surround. The suspension attaches to the driver at its widest diameter section connecting it to the basket (the structure that holds all the elements of a dynamic speaker driver together). The voice coil is attached to the smallest diameter section of the diaphragm. The voice coil interacts with a stationary magnet (in a traditional dynamic speaker driver) to create movement. This movement is transferred to the diaphragm to create sound. The spider attaches to the diaphragm or voice coil and holds the voice coil in proper relation to the magnet as well as acting as a spring or bungee to bring the diaphragm back to its resting position. iaphragms come a wide range of sizes and materials depending on their function. Most of those used for bass reproduction are eight inches in diameter or larger with subwoofer diaphragms typically running from twelve to eighteen inches in diameter. Midrange drivers (those that reproduce the middle frequencies including the human voice) range in size from six or seven inches to three or so inches in diameter with most being five to six inches in diameter. Tweeters that handle high-frequencies tend to use domes and are usually only about an inch in diameter. iaphragms must be stiff and sturdy while also being light weight. They need to be able to move and respond quickly, necessitating light weight. They also should not flex or deform as they move (which would cause distortion), requiring a strong structure. Most domes are made from some sort of light-weight metal (typically aluminum or titanium), silk or a light weight plastic. Midranges and woofers are typically cones that are made of some type of treated plastic or strong, specially formed paper. Diaphragms are what make it possible for speakers to generate sound by vibrating and exciting the surrounding air with their vibrations.