Figure 2. Power spectrum distribution of normal and Pathological heart sound signals in five auscultation locations (Curve naming used the format ‘*-#’, where ‘*’ represents either normal (n) or abnormal (a), and ‘#’ represents the signal acquisition area (A to T))

From

Spectrum Characteristics Analysis and Recognition of CHD Heart Sound in Five Auscultation Locations

Sheng MIAO, Jian’e Dong, Jingyu Hou, Zhong Lihui

Journal of Biomedical Engineering and Technology. 2020, 8(1), 14-24 doi:10.12691/jbet-8-1-3