trillSpan question:

[Kenneth Wolcott]

Hi;

  I have trouble understanding how to implement the \startTrillSpan
and \stopTrillSpan.

  I have two screenshots.

  The first is an obvious \trill, no span needed.

  The second requires the span, but I don't know how to place the
\stopTrillSpan.

  I see the trill section in the Notation Reference.  It does not help
me understand how to place the \stopTrillSPan correctly.  I could
place the \stopTrillSpan after the following note, but that certainly
would be correct, right?

  Another related question: what is the difference in the actual
performance of the two types?

  This is partially explained by Wikipedia:

"A rapid alternation between the specified note and the next higher
note (determined by key signature) within its duration, also called a
"shake". When followed by a wavy horizontal line, this symbol
indicates an extended, or running, trill. In music up to the time of
Haydn or Mozart the trill begins on the upper auxiliary note"

So does this mean that a dotted-quarter note trill will only be
"trilled" for a quarter note duration and will the spanner indicate
the full dotted quarter duration?

Thanks,
Ken Wolcott

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