\version "2.18.2"

\header {
  title = "Prova"
  composer = "P. Bacchetta"
}

global = {
  \key c \major
  \time 4/4
}

jazzGuitar = \relative c' {
  \global
  % Music follows here.
  
}

\score {
  \new Staff \with {
    midiInstrument = "electric guitar (jazz)"
    instrumentName = "Jazz guitar"
  } { \clef "treble_8" \jazzGuitar }
  \layout { }
  \midi {
    \tempo 4=100
  }
}