Aortic area: Right sternal border, 2nd intercostal space. S2 is louder than S1.
Pulmonic area: Left sternal border, 2nd intercostal space.
Erb's point: Left sternal border, 3rd intercostal space.
Tricuspid area: Left lower sternal border, 4th intercostal space, not always audible.
Mitral (Apex) area: Left midclavicular line, 5th intercostal space. The S1 is loudest in this area. S3 and S4 are heard here.
