I have been admiring this piece, here played on an interesting 11-string. It appears to be 10-string with an additional string, and then the player puts a capo only across the first six strings (or is it seven?), turning the guitar into an alto guitar. Here is the score to the piece he's playing, although he may be using 3=g, not 3=f#.
http://tinyurl.com/p37l53u
https://youtu.be/abbSA08CBP0
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