5 Chord tremolos look like beams, but are a kind of repeat symbol.
6 To avoid confusion, chord tremolo beams do not reach the stems, but
7 leave a gap. Chord tremolo beams on half notes are not ambiguous,
8 as half notes cannot appear in a regular beam, and should reach the
14 \context Voice \notes\relative c' {
15 \repeat "tremolo" 8 { c16 d16 }
16 \repeat "tremolo" 4 { c16 d16 }
17 \repeat "tremolo" 2 { c16 d16 }
22 linewidth = 40*\staffspace