Abstract: A phonocardioscope apparatus is provided for monitoring heart functions. The apparatus comprises an acoustical transducer for detecting the sound of heartbeats and producing an analog electrical signal in response thereto. An analog-to-digital converter converts the analog heartbeat signal to a digital heartbeat signal. The transducer may be coupled to the analog-to-digital converter by means of a non-linear amplifier which enhances the signal/noise ratio of the signal. The output of the analog-to-digital converter, which is the digital heartbeat signal, is stored in at least one RAM and the data stored in the RAM is then displayed on the liquid crystal display and may be printed as well. A microprocessor functioning as a CPU controls the operation of the A/D converter, the RAMs and the liquid crystal display. Further, a keyboard is coupled to the apparatus for permitting an operator to select the mode or characteristics of the display.