During the history human were looking ways how to enhance hearing sense.   American Indians used to put their ear on the ground to listen if flocks are coming. Japanese still keep fish tanks which may report that earthquake is coming when human body is still unable to detect it. Stethoscope is another instrument which is used to determine unusual sounds in the body. I really liked it’s definition in Wikipedia:  the stethoscope is an acoustic medical device for auscultation, or listening to the internal sounds of an animal or human body. It is often used to listen to lung and heart sounds. It is also used to listen to intestines and blood flow in arteries and veins. In architectural language cities also have lung (green areas), heart (center), arteries and veins (infrastructure).

What could be the instrument listen to the city health when human senses are too weak? And how it would sound?