This image compares the sound frequency reception between the stethoscope bell and diaphragm. It features labeled illustrations of both the bell and diaphragm in use on a chest, showing their anatomical contact points including skin, ribs, and lung tissue. Two graphs depict frequency ranges: the bell captures low-frequency sounds between 20 to 200 Hz, while the diaphragm detects higher frequencies from 100 to over 2000 Hz. The chart also associates each part with specific heart and lung sounds, highlighting their clinical use for different auscultation purposes.