Subwoofer cone material must be rigid and very light. Most subwoofer cones are made using a composite of paper and polypropylene to give impart that lightness and rigidity. Using polypropylene also adds a layer of protection for the speaker by imparting resistance to water, mold and mildew. The subwoofer cone is the part of the speaker that is connected to the cage by the surround, and also to the cone on the speaker coil, which creates the up and down movements that create the sound you hear. Other materials such as Kevlar, aramid fiber and silk have also been used to make subwoofer cones.
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