acoustic condition monitoring

Data from acoustic condition monitoring of a milling process. During the process, several test parts were milled and acoustic data was recorded using a MEMS microphone.
One file shows two different tools used during milling, one for rough (face) milling with five cutting edges, and one with four cutting edges.

The other files show the data from different parts being milled, with the tool having four cutting edges. There were seven parts milled in total.
As the parts progress, it can be seen that the acoustic data changes, indicating wear and damage in the tool.