Re: crescendi/decrescendi on one note in Lilypond? and how does a pianist do this?

[David Nalesnik]

Hi Ken,

On Sat, Jan 30, 2021 at 12:28 AM Kenneth Wolcott
<kennethwolcott@gmail.com> wrote:
>
> Hello;
>
>   I have another simple engraving question.
>
>   I frequently see a crescendo or decrescendo on a single note
> (usually a whole note).
>
>   How does a pianist do this? I can see a wind instrument or even a
> string instrument doing this.

It can be a description of the resulting sound rather than an
instruction for the pianist to execute.  So just a visual reflection
of the fact that the note gets softer (of its own accord in the
sustained note here).

There's also the possibility that, for whatever reason--as a
psychological cue to the player, perhaps--something actually
impossible is being notated.  Something like (off the top of my head):

{
  a'1\p\<
  <a'' c''' e''' a'''>4->-.\f\!
}

But in your example, the decrescendo applies to both staves.  It looks
like there is motion in the cropped part.

(As an aside, there's interesting discussion of seemingly impossible
notation in early Romantic piano music in Rosen's The Romantic
Generation, IIRC.)

>
>   And, even more importantly, how to engrave this?
>

If there is music beyond, simply end the hairpin on the following note or rest:

\version "2.21.5"

{
  a'1\>
  R1\!
}

If there is nothing, you could use a trick like ending the hairpin on
a zero-length spacer:
{
  a'1\>
  s1*0\!
}

(BTW, since the hairpins apply to both staves, you might consider
using a Dynamics context.)

>   Two measure screenshot provided: first measure I understand; the
> second measure I don't.
>
> Thanks,
> Ken