Of course there are many more sounds and techniques invented and used for the harp, than are included in our video of chapter 9. For example: Combinations of extended techniques, scratching or hitting the strings and body of the harp with all kinds of materials, detuning or amplifying wherever you want – there are almost no limitations here!
We will soon add a video with excerpts of very new music, to give you an idea of what other composers have been inventing in recent years.
For the time being, here are two links to inspire you!
Concerning symbols for extended techniques, we show only a very few basic signs of chapter 9, since only these are common to all harpists. There are a lot more signs in use, but not every harpist will immediately recognize them. We do not want to give the impression that certain symbols are standard, when in fact they are not. You are better off explaining non-standard symbols at the start of the piece, or adding other explanatory media, like a videolink.