Both the bell and diaphragm are used interchangeably for all types of sounds and pitches
The bell is used for high-pitched sounds, while the diaphragm is used for low-pitched sounds
The diaphragm is used for high-pitched, like bowel sounds, while the bell is for low-pitched sounds
The diaphragm is used for softer sounds, like a murmur, while the bell is used for louder sounds