Development of An Earplug Equipped with Active Noise Reduction (Ontwikkeling van een Oordrp met Active Geluidreductie).
Abstract
In cooperation with Philips Asset and Groeneveld Etcea an earplug was developed equipped with an active noise reduction system. The goat, to achieve a extra active attenuation of 20 dB, is almost reached. An attenuation of 18 dB was obtained for frequencies below 500 Hz. Reduction of the loop-gain results in an extension of the frequency range with a tower attenuation. The system uses a specific telephone with an improved frequency response with respect to the standard walkman telephones. The casts of both telephone types are equivalent. The special designed telephone, however, has a low impedance which requires a complex adaptation to the electronic control unit. The use of a personal moulded earplug as connection between the ear canal and the electra acoustic part of the system gives some leakage. Application of a standard earplug gives better results and is general applicable, however, the fixation with the ear canal is not as robust as with a personal moulded plug.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 18, 1995
- Accession Number
- ADA307480
Entities
People
- H. J. Steeneken
- J. A. Verhave
- S. T. Goverts