Abstract: A non-invasive apparatus for detecting turbulent flow in a cerebrovascular system of a patient without use of software, includes a planar, circular head adapted to be placed against an eye socket of the patient. A microphone in the head detects an acoustic signal from the cerebrovascular system and converts the acoustic signal to an electrical signal. A filter passes only a portion of the electrical signal having a frequency in a range between 350 Hz and 1,800 Hz as a filtered electrical signal, so as to eliminate extraneous signals due to other than vascular flow. A headset has at least one ear piece with a speaker therein for converting the filtered electrical signal to an audio signal in order to detect the turbulent flow in the cerebrovascular system of the patient.