Abstract: A chest piece for a stethoscope has a housing with a cavity. The cavity has a cavity surface which is paraboloid in shape, having an apex, an axis, and a focal point. The cavity terminates at the apex and an opening, and the focal point resides in the cavity. A transducer is positioned at the focal point. The parabolic shape of the cavity surface acts to reflect sound waves transmitted normal to the opening to the transducer, while reflecting other sound waves. A mechanical wave guide with a series of parallel passages preferably extends across the opening. Preferably, a membrane with a convex surface covers the opening. The cavity is preferably filled with a liquid or gel having physical characteristics similar to human flesh. To reduce noise from motion of the chest piece across the skin, the stethoscope can be activated by a pressure switch responsive to fluid pressure inside the cavity.

Abstract: An electronic stethoscope emulates the frequency response of a standard acoustical stethoscope in both bell and diaphragm modes, while providing additional features attainable only with an electronic stethoscope, such as signal amplification, noise reduction, wider bandwidth, and mode selection. The electronic stethoscope includes spectrally separate idealized diaphragm and idealized bell modes. The idealized diaphragm mode and the idealized bell mode each include emphasized passbands and de-emphasized passbands. The emphasized passbands are spectrally separate. In addition, the electronic stethoscope also includes a wideband mode, which permits the user to hear high frequency sounds such as those associated with mechanical heart valves, lung sounds, and the like.

Abstract: An electronic stethoscope having several modes of operation to process acoustic signals to provide filtered signals useful for diagnosis. In one mode of operation the stethoscope substantially provides only acoustic signals generated by biological activity of the heart. In another mode of operation, the acoustic stethoscope substantially provides only acoustic signals generated by biological activity of the lungs. In another mode of operation, the electronic stethoscope disproportionately amplifies abnormal heart sounds and normal heart sounds to enhance diagnosis of heart abnormalities. The electronic stethoscope is operated in a manner similar to a conventional acoustic stethoscope and has similar spectral characteristics, thus allowing a user with acoustic stethoscope experience to easily use the electronic stethoscope.

Abstract: A cover encloses the center sound tube and head of a stethoscope. The head cover can be extended over the head of a stethoscope and may be separate from or coupled to the center sound tube cover. A cover flap can extend over an upper end of the center sound tube cover and between lateral sound tubes of the stethoscope to preclude an unintentional engagement with hair.

Abstract: An electronically amplified, recording, stereophonic stethoscope, EARSS, utilizes binaural phase effect from two probes held in one chestpiece with amplifier. Skin contacts in probes are small, to localize, pliable, to fit body curves, shaped for acoustic amplification, spread for wide pickup. Connecting tubes are flexible, with dimensions and properties that protect, isolate, reinforce and adapt skin contacts to microphones. Adapters for multiple stereophones, listeners, recorders, videocameras and imaging of induced sound, facilitate teaching, consultation and sharing with patients. More sensitive and specific detection and recognition of diseases and functions stimulate more careful auscultation by physicians, new uses and tests, and increased lay use of a classic professional symbol.