Abstract: An ear piece assembly (10, 100, 200, 300, 500, 600, 700, 800, 900, 1000) designed for a stethoscope or other headpiece, and configured to allow rotation of an ear tip (20, 120, 220, 320, 420, 520, 620) of the assembly about a central axis (relative to the rest of the assembly) and to allow limited off axis movement of the ear tip (relative to the rest of the assembly). In typical embodiments, the ear piece assembly is designed to fit a user's ear canal and stay in place during typical use without rotational or off axis movement of the ear tip relative to the ear canal, and to provide substantially more comfort to the user than would a headpiece with a conventional ear tip assembly, particularly for prolonged wearing by the user. Other aspects of the invention are a headpiece (e.g.

Abstract: An ear piece assembly (10, 100, 200, 300, 500, 600, 700, 800, 900, 1000) designed for a stethoscope or other headpiece, and configured to allow rotation of an ear tip (20, 120, 220, 320, 420, 520, 620) of the assembly about a central axis (relative to the rest of the assembly) and to allow limited off axis movement of the ear tip (relative to the rest of the assembly). In typical embodiments, the ear piece assembly is designed to fit a user's ear canal and stay in place during typical use without rotational or off axis movement of the ear tip relative to the ear canal, and to provide substantially more comfort to the user than would a headpiece with a conventional ear tip assembly, particularly for prolonged wearing by the user. Other aspects of the invention are a headpiece (e.g.

Abstract: An active stethoscope or other sound detection device, including a diaphragm, at least one floating mass mounted to the diaphragm (at at least one coupling point of the diaphragm), and an acoustic transducer mounted to the floating mass. Preferably, each floating mass is configured and mounted so that as each floating mass and each coupling point of the diaphragm move in sympathy with acoustic waves (to be detected) that impinge on the diaphragm, the acoustic transducer rides with and is stabilized by the floating mass to which it is mounted and the diaphragm is stabilized by each floating mass. The acoustic transducer can be of any of many different types. For example, it can be a microphone, or an optical, capacitive, or inductive transducer. The diaphragm can have an isolating portion which absorbs acoustic surface wave energy incident thereon, or otherwise prevents or reduces transmission of acoustic surface waves through the isolating portion between regions of the diaphragm.