14-string guitar (or even more) ...and it sounds FANTASTIC!

#2
Oh. It's just a Warr guitar. People have been doing that for years.
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#3
Pretty interesting concept! He does what I imagine it done with any extended range guitar: think of it more of a harp/piano/guitar hybrid.

For the guitar itself, it looks like two 7 strings guitars made as if they were conjoined twins.
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