Subminiature Speaker Employs Ferrofluid Damping Technique

The ED Series subminiature speakers employ a ferrofluid damping technique, which uses a viscous liquid (ferrofluid) that is injected into the receiverÕs motor to reduce the armature excursion near resonance. Developed about 25 years ago, ferrofluids are colloidal suspensions of microscopic permanent magnets. This approach offers the advantages of screen damping without the problems associated with wax accumulation in the screen. The ED Series speakers are intended for use in low-profile headsets and earphones for both communications and professional audio applications. EMKAY INNOVATIVE PRODUCTS, Itasca IL. (630) 250-5930.