Here is a uncommon derivative of the classical guitar : an octave classical guitar, which is ... to say ... tuned an octave above a traditional acoustic guitar.
While loving the sound of the mandolin, I always wondered how to mix this kind of high sound with a smoother nylon strings flavour. I founded it when I got this delicious soprano Francisco classical guitar in 2010. Tuned like my mandolin (from bass to high : C#, F#, B, E, G#, C#) it allows a lead polyphonic playing ideal for mediaeval-like pieces of music. The sound almost reminds a lute or a harp, very warm, sweet and gentle, but you can also play dynamic rythms on it, in a Jethro Tull style. Unfortunately, this guitar didn’t find his way on a Minimum Vital album yet, but I hope I will play it in a future recording project.
Here you can see a rough video of me practicing at home with this unusual guitar. Note the decorations on the sound board were made by my son Gaël.