I don't think music sees innovation the same was as other fields do. The two categories of innovation are "Make it better" and "Make it different". Basically objective improvement versus subjective improvement. Music has an awful lot of innovations that don't make an improvement so much as they provide a change of scene.
The electric guitar is a great example. It was designed to make an acoustic guitar sound louder. Didn't do that in the slightest and did not improve anything about what people liked about guitar as it was back then. What it did do however is allow people access to a whole palette of sounds that didn't exist before. Not better or worse, just different and new.