Thank you to Marek, Lusaka and Lucy for your comments.
Marek Yes it's me playing the guitar parts 3, actually a capo II would avoid some resonances and give more clarity to the whole, but it would lose the side a little darker than I like this tone.
This work is also one of my favorites, I would have liked to learn to play the piano only to play this concerto movement !!! but being a guitarist, the only solution is treason, an adaptation of this masterpiece for 3 guitars, it's like the Mona Lisa reproduction in black and white on a stamp but it's still better than nothing!!!