Introduced here are electronic stethoscope systems designed to simultaneously monitor sounds originating from within a body under examination and the ambient environment. An electronic stethoscope system can include one or more input units that are connected to a hub unit. Each input unit may have at least one auscultation microphone and at least one ambient microphone. To improve the quality of sound recorded by an input unit, a processor can apply a noise cancellation algorithm that considers as input the audio data produced by the auscultation microphone(s) and the audio data produced by the ambient microphone(s). The audio data may be digitized directly in the input unit, and then transmitted to the hub unit for synchronization. For example, by examining the audio data produced by the ambient microphone(s), the processor may discover which digital artifacts, if any, should be filtered from the audio data produced by the auscultation microphone(s). The processor may reside within the input unit or the hub unit.