>The organ is, together with the clock, the most complex of all mechanical instruments developed before the Industrial Revolution. Among musical instruments its history is the most involved and wide-ranging, and its extant repertory the oldest and largest. Despite its essentially indirect and therefore relatively inflexible production of sound, no other instrument has inspired such avowed respect as the organ, ‘that great triumph of human skill … the most perfect musical instrument’ (Grove), ‘in my eyes and ears … the king of instruments’ (Mozart, letter to his father, 17–18 October 1777).
> The organ is, together with the clock, the most complex of all mechanical instruments developed before the Industrial Revolution
Or to put it more strongly: the most complex machines on the planet for roughly 2000 years. The starting point usually acknowledged is Ctesibius's hydraulis, an organ with a simple automatic pump (no calcant or animal labour required) and pressure regulation. That was about 250BC. They were still producing innovations well after the industrial revolution, e.g. pneumatic relays.
>The organ is, together with the clock, the most complex of all mechanical instruments developed before the Industrial Revolution. Among musical instruments its history is the most involved and wide-ranging, and its extant repertory the oldest and largest. Despite its essentially indirect and therefore relatively inflexible production of sound, no other instrument has inspired such avowed respect as the organ, ‘that great triumph of human skill … the most perfect musical instrument’ (Grove), ‘in my eyes and ears … the king of instruments’ (Mozart, letter to his father, 17–18 October 1777).
Stephen Malinowski's famous YouTube channel of animated graphical scores has a great selection of organ pieces: https://www.youtube.com/watch?v=JXaCmhAMnHs&list=PLA20FE13E9...
St. Cecilia, pray for us!