GBT Tulsa

The terms for different speaker drivers differ depending on the application. In 2-way loudspeakers, there is usually no driver called "mid-range". Home stereos use the designation "tweeter" for high frequencies whereas professional audio systems for concerts typically designate all types of high frequency drivers as "HF" or "highs" or "horns".

The spider is usually made of a corrugated fabric disk, generally with a coating of a material intended to improve mechanical properties. Unusually, a German manufacturer, Klangfilm, used bakelite for spiders in some of its early drivers, and another German company currently offers a spider made of wood. The surround can be a roll of rubber or foam, or a ring of corrugated fabric (often coated), attached to the outer circumference of the cone and to the frame. The choice of suspension materials affects driver lifetime, especially in the case of foam surrounds which are susceptible to aging and environmental damage.

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