In Lllypond, connect half note with 8th note beams for guitar arpeggio

Question

I've come across guitar sheets several times where the bass note of an arpeggiated chord, written as a half note (to keep the string ringing) is connected to the beam of the 8th notes following, for example in this post. How can I engrave this in Lilypond?

Here are some ideas I tried, but none is really satisfying: (\tweak in 4th measure inspired by this answer)

\version "2.16.2"


\score {

  \new Staff <<

    \new Voice="mel" {
      \voiceOne
      \relative c'
      {
                % 1st measure, with rests
    r8 g' c e r a, d fis |

                % 2nd measure, simultaneous notes in two voices with different lengths
    c,8 g' c e d, a' d fis |

                % 3rd measure, omit note heads -> stem on wrong side of half note
    \omit NoteHead c,8 \undo \omit NoteHead
    g' c e
    \omit NoteHead d, \undo \omit NoteHead
    a' d fis |

                % 4th measure, \tweak does not do anything apparent here...
    \tweak duration-log #2 c,8 g' c e \tweak duration-log #2 d, a' d fis |

                % 5th measure, 8th notes in bass is not really what I intend
    c,8 g' c e d, a' d fis |
      }
    }

    \new Voice="bas" {
      \voiceTwo
      \relative c'
      {
    \repeat unfold 3 {c2 d} | s1
    c8 s4. d8 s4.
      }
    }

  >>

  \layout {}

}

Thanks!

Answer 1

I don't really know exactly what you want the final output to look like. But here are some suggestions.

\score { 
    \new Staff { 
% 1. different voices (with rests)
        << { r8 g' c'' e'' r a' d'' fis'' } 
            \\ { c'2 d' } >> |

% 2. merging the heads in different voices (as already suggested)
        \mergeDifferentlyHeadedOn
        << { c'8 g'8 c'' e'' d' a' d'' fis'' } 
            \\ { c'2 d' } >> |

% 3. incorporating the minims into the beams (by tweaking the durations correctly)
        \tweak duration-log #1
            c'8 g' c'' e'' 
        \tweak duration-log #1
            d'8 a' d'' fis'' |

% 4. making the minims have quaver length, and extending the beam a little
        \stemUp
        c'2*1/4 \set stemLeftBeamCount = #1 g'8 c'' e''
            d'2*1/4 \set stemLeftBeamCount = #1 a'8 d'' fis'' |
    }
}

NB: in my code, I have used absolute pitches not relative pitches.

Answer 2

There is an option to do exactly what you want.

For some reason the complete example seems to be temperamental and isn't displaying properly, but the Lilypond keyword is \mergeDifferentlyHeadedOn. Look it up in the documentation.

    { \relative c' { 
       <<
      { \mergeDifferentlyHeadedOn
        c8 g' c e d, a' d fis }
      \\ 
      { c,2 d }
      >>
    } }