---- On Fri, 10 May 2024 15:07:33 +0800 Mark Knoop wrote ---
> Haven't tested, but I think Text_spanner_engraver lives in Voice, rather than
> Staff. Try removing from the \global Voice, otherwise send a WME.
Ah... indeed. That does take care of it.
\new PianoStaff \with {
instrumentName = "古筝"
shortInstrumentName = "古筝"
} <<
\new Staff = "up" << \global \zhengR >>
\new Staff = "down" % \with { \remove Text_spanner_engraver }
<<
\clef bass
\new Voice \with { \remove Text_spanner_engraver } { \global }
\zhengL
>>
>>
Kieren's solution also works, with a bit less syntax.
Thanks to both!
hjh