Abstract: Described embodiments include a system, including a garment, configured to cover at least a portion of a body of a subject, one or more sound transmitters coupled to the garment, configured to transmit sound through the body of the subject, and a plurality of sound detectors coupled to the garment. The sound detectors are configured to detect the transmitted sound following passage of the transmitted sound through the body of the subject, to detect body sound emanating from the body of the subject, and to generate a plurality of sound-detector outputs in response to detecting the transmitted sound and the body sound. The system further includes a processor, configured to process the sound-detector outputs, and to generate a processor output in response thereto. Other embodiments are also described.

Abstract: A medical device (20) includes a case (32), having a front surface that is configured to be brought into contact with a body of the living subject (24). A microphone (34) is contained in the case and configured to sense acoustic waves emitted from the body and to output an acoustic signal in response thereto. A proximity sensor (56) is configured to output a proximity signal indicative of contact between the front surface and the body. At least one speaker (49) is configured to output audible sounds. Processing circuitry (50) is coupled to detect, in response to the proximity signal, that the front surface is in contact with the body, and in response to the detected contact, to process the acoustic signal so as to generate an audio output and to convey the audio output to the at least one speaker.

Abstract: A medical device includes an acoustic transducer, which is configured to sense infrasonic waves emitted from a body of a living subject with a periodicity determined by a periodic physiological activity and to output an electrical signal in response to the sensed waves. At least one speaker is configured to output audible sounds in response to an electrical input. Processing circuitry is configured to process the electrical signal so as to generate a frequency-stretched signal in which infrasonic frequency components of the electrical input are shifted to audible frequencies while preserving the periodicity of the periodic physiological activity in the frequency-stretched signal, and to input the frequency-stretched signal to the at least one speaker.

Abstract: Described embodiments include a system (74), including a garment (76), configured to cover at least a portion of a body of a subject, one or more sound transmitters (92) coupled to the garment, configured to transmit sound (128) through the body of the subject, and a plurality of sound detectors (22, 96) coupled to the garment. The sound detectors are configured to detect the transmitted sound following passage of the transmitted sound through the body of the subject, to detect body sound (25) emanating from the body of the subject, and to generate a plurality of sound-detector outputs in response to detecting the transmitted sound and the body sound. The system further includes a processor (98), configured to process the sound-detector outputs, and to generate a processor output in response thereto. Other embodiments are also described.