When athletic height jumping was considered done and perfected, there was the Fosbury flop which opened new possibilities. Do you think there was such a moment in the music history? When someone showed how things can be done and from there everyone is using his/her technique?
I would say going from analogue to digital recording. Digital made edits possible that where impossible before.
i think getting any kind of reliable recording was a bigger jump. it totally transformed the way we listen to music.
the other thing is microphones and speakers. changed live music totally.