12 strings is one thing, but how about microtonal? That's instead of adding strings, you add frets!
If you haven't heard them yet, you're in for a wild ride: https://www.youtube.com/@AnginePoitrine
It is still worth noting that the microtones used by Angine de Poitrine are usually just transient notes, and could instead be played portamento with smooth transitions between the notes (eg on a fretless board) in most situations. It still sounds really cool, though, and certainly a technical and musical accomplishment. But the music itself still follows the usual patterns closely.
A bit spotty, but alright; meanwhile the Italian instrument makers said guitar-harp? Hold our expressos, this'll take some discipline:
That's the first time I've heard microtonal work in a rock setting. Pretty good!
I see your added frets, and raise "add frets on the fly using Lego":
In the early days of the guitar it had tied gut frets, it was microtonal by nature and you could move the frets for different temperaments. Then in the 19th century things changed and the guitar got fixed metal frets, ever since people have been trying to figure out how to have the benefits of both. 1852 is the first attempt that I know of.
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