I visited conservatoire des arts et metiers museum in Paris a couple years ago. It is full of fascinating scientific devices from the past. Among then was the t

I visited conservatoire des arts et metiers museum in Paris a couple years ago. It is full of fascinating scientific devices from the past. Among then was the timbre analyser. I was blown away. A purely analogic spectrum analyser. https://commons.wikimedia.org/wiki/File:Timbre_analyser-CNAM_12605-IMG_5057-gradient.jpg https://commons.wikimedia.org/wiki/File:Timbre_analyser-CNAM...