Hitting your elbow with the tuning fork hurts, dumb doctors hit their elbows with the tuning fork. Smart dictors hit their patient's elbow with the tuning fork. Smarter doctors mask the pain they cause the patient by hitting their elbow by then asking did you feel that?
He has the pressures mixed up on the stethoscope functions. You use light pressure for the use of the diaphragm and harder pressure for it to act as a bell. The tunable diaphragms are a major upgrade from a normal stethoscope and I would highly recommend it