Prof. Dan Levitin ex music industry mogul cum psychoacoustician

• 1) Tanning. This made possible the preparation of skins for stretching over things to make early drums.
• 2) The drill/carving knife. This made possible the boring of holes in wood and bone.
• 3) Notation (and as you suggested, Perry, the printing press). Together, these emancipated music from small, insulated communities of people, and allowed for music to be learned by people who had never heard a piece before -- this is the beginning of music going global.
• 4) The concert hall. The first concert hall didn't arise until the 1600s. The Greeks had performance arenas for sporting and theater events, but in western society, concert halls didn't appear until the 17th century. This created two classes of people: musicians and listeners. The idea of a musical expert or performer was introduced consequent to this.
• 5) Tuning gears/pegs. This made possible the development of stringed instruments. (You had actually traced this back to Archimedes.)
• 6) Marconi - wireless transmission. This allowed people in one part of the world to hear music from another part of the world, or to hear music without having to leave their homes! This must have had an enormous impact on the sheer amount of an variety of music and individual could be exposed to.
• 7) Transistor. This made music portable. We take for granted that people can now hear music at the beach, in their cars, wherever they want.
• 8) Piano. Great harmony engine.
• 9) Tape/vinyl. It remains to be seen if this will have a big impact historically. but it sure had a big impact on my own life. This made it possible to preserve performances that can be played back anywhere, anytime, for a virtually unlimited number of times.
• 10) MTV. This changed our criteria for what constitutes "good music" from being based purely on the song to being based purely on the sex appeal.