Michael A. Klasco
Menlo Scientific, Ltd., 39 Menlo Pl., Berkeley, CA 94707
Perhaps the drive behind a number of important new materials developments for speakers was the compact disc. The CD brought wide dynamic range with extended bass response into the home and car and ``digital-ready speakers'' have become more than just a marketing pitch. How are speaker engineers increasing excursion, thermal power handling, and maintaining performance characteristics at higher sound levels, while improving reliability? Specific solutions such as carbon fiber and Kevlar woven and nonwoven composite cones, new cone forming technologies, injection molded adhesiveless suspension surrounds, thermally conductive adhesives, thermally (but nonelectrically) conductive voice coil formers, high-temperature voice coil wire insulation and adhesives, a new magnetic geometry for high-excursion linear travel, ferrofluids for woofers, high-heat emmisivity plating techniques, and other fabriction and materials solutions will be briefly discussed. Advances in materials extend to enclosure materials, and a brief survey of developments in this related field will be mentioned. Additionally, test and measurement procedures to objectively quantify these enhancements will be touched upon.