Re: Staff and voice definitions

[Carl Sorensen]

David Fedoruk <david.fedoruk <at> gmail.com> writes:

> 
> Using Lilypond keeps challenging assumptions I have made about WEM
> (Western European Music) notation. In most cases, there is a voice
> which goes with each staff, but I don't see that the creation of a
> voice is  part of the staff engraver or any of the engravers that go
> along with it.

In my experience, one of the hardest things about LilyPond is understanding the
logic behind it.  I think that Han-Wen and Jan have done a masterful job of
architecting a system that is flexible and extensible. With all this power,
sometimes the function can be difficult to understand.

Recognizing that I'm not an expert, I'll give you my best shot at explaining
things, which others can feel free to correct, as they'll undoubtedly know
better than me.

My understanding is that a voice needs to be associated with a staff in order to
get the notes printed in a staff.  However, the voice is not a sub-context of a
staff, because the voice can be switched to be part of a different staff.
> 
> Can I assume that the creation of a music which goes between the {} is
> separate from the staff?

If you don't explicitly create a voice, a voice context is automatically
created, and associated with the current staff.

> 
> A follow-up question is can a Piano staff which has two staffs which
> work together, have only one { music } and still run between both
> staves? A single voice played by two hands.

Yes, this can be easily done.  All one needs to do is to use the \autochange
keyword.  This is described in section 7.1.1 Automatic Staff Changes of the 2.10
documentation.  You can also manually change staffs; this is described in
section 7.1.2 Manual Staff Changes. 


Good luck,

Carl Sorensen