Changing the size of a staff with a music function

To change the size of an individual staff, you would \set the fontSize property of the Staff context, and \override the 'staff-space, and 'thickness properties of the StaffSymbol.

This snippet shows how to simplify this process by defining a music function called staffSize. It works as a macro and sets each of these three properties for you. (It can actually be used in any context that has a font size engraver, not just Staff contexts.)

If you want to resize all the staves in the file (and all the text as well), a simpler way is to use #(set-global-staff-size xx).