+@node Ambitus
+@unnumberedsubsubsec Ambitus
+@cindex ambitus
+
+The term @notation{ambitus} or @notation{ambit} denotes a range of
+pitches for a given voice in a part of music. It may also denote
+the pitch range that a musical instrument is capable of playing.
+Ambits are printed on vocal parts, so performers can easily
+determine if it meets their capabilities.
+
+Ambits are denoted at the beginning of a piece near the initial
+clef. The range is graphically specified by two note heads that
+represent the minimum and maximum pitch. To print such ambits,
+add the @code{Ambitus_engraver} to the @code{Voice} context, for
+example:
+
+@lilypond[verbatim,quote,ragged-right]
+\layout {
+ \context {
+ \Staff
+ \consists Ambitus_engraver
+ }
+}
+
+\relative \new Staff {
+ as'' c e2 cis,2
+}
+@end lilypond
+
+If you have multiple voices in a single staff and you want a
+single ambitus per staff rather than per voice, add the
+@code{Ambitus_engraver} to the @code{Staff} context rather than to
+the @code{Voice} context:
+
+@lilypond[verbatim,quote,ragged-right]
+\new Staff \with {
+ \consists "Ambitus_engraver"
+}
+<<
+ \new Voice \with {
+ \remove "Ambitus_engraver"
+ } \relative c'' {
+ \override Ambitus #'X-offset = #-1.0
+ \voiceOne
+ c4 a d e f2
+ }
+ \new Voice \with {
+ \remove "Ambitus_engraver"
+ } \relative c' {
+ \voiceTwo
+ es4 f g as b2
+ }
+>>
+@end lilypond
+
+@noindent
+This example uses one advanced feature,
+
+@example
+\override Ambitus #'X-offset = #-1.0
+@end example
+
+@noindent
+This code moves the ambitus to the left. The same effect could
+have been achieved with @code{extra-offset}, but then the
+formatting system would not reserve space for the moved object.
+
+@seealso
+
+Snippets: @lsrdir{pitches},
+@lsr{vocal,ambitus@/.ly}.
+
+Internals reference: @internalsref{Ambitus},
+@internalsref{AmbitusLine}, @internalsref{AmbitusNoteHead},
+@internalsref{AmbitusAccidental}, @internalsref{Ambitus_engraver},
+@internalsref{Staff} and @internalsref{Voice}.
+
+
+@refbugs
+
+There is no collision handling in the case of multiple per-voice
+ambitus.
+
+
+@node Note heads
+@subsection Note heads
+
+@menu
+* Easy notation note heads::
+* Shape note heads::
+* Improvisation::
+* Special noteheads::
+@end menu
+
+@node Easy notation note heads
+@unnumberedsubsubsec Easy notation note heads
+
+@cindex note heads, practice
+@cindex note heads, easy notation
+@cindex easy notation
+@cindex Hal Leonard
+
+The @q{easy play} note head includes a note name inside the head.
+It is used in music for beginners
+
+@lilypond[verbatim,quote,ragged-right,fragment,staffsize=26]
+\setEasyHeads
+c'2 e'4 f' |
+g'1
+@end lilypond
+
+The command @code{\setEasyHeads} overrides settings for the
+@code{NoteHead} object. To make the letters readable, it
+has to be printed in a large font size. To print with a larger
+font, see @ref{Setting the staff size}.
+
+@refcommands
+
+@funindex \setEasyHeads
+@code{\setEasyHeads}
+
+@seealso
+
+Snippets: @lsrdir{pitches},
+
+Internals reference: @internalsref{NoteHead}.
+
+
+@node Shape note heads
+@unnumberedsubsubsec Shape note heads
+
+@cindex note heads, shape
+
+In shape note head notation, the shape of the note head
+corresponds to the harmonic function of a note in the scale. This
+notation was popular in nineteenth-century American song books.
+
+Shape note heads can be produced by setting @code{\aikenHeads} or
+@code{\sacredHarpHeads}, depending on the style desired.
+
+@lilypond[verbatim,fragment,relative=1]
+\aikenHeads
+c8 d4 e8 a2 g1
+\sacredHarpHeads
+c,8 d4. e8 a2 g1
+@end lilypond
+
+Shapes are typeset according to the step in the scale, where
+the base of the scale is determined by the @code{\key} command.
+
+@funindex \key
+@funindex shapeNoteStyles
+@funindex \aikenHeads
+@funindex \sacredHarpHeads
+
+Shape note heads are implemented through the
+@code{shapeNoteStyles} property. Its value is a vector of
+symbols. The k-th element indicates the style to use for the k-th
+step of the scale. Arbitrary combinations are possible, e.g.:
+
+@lilypond[verbatim,fragment,relative=1]
+\set shapeNoteStyles =
+ ##(cross triangle fa #f mensural xcircle diamond)
+c8 d4. e8 a2 g1
+@end lilypond
+
+@seealso
+
+Snippets: @lsrdir{pitches}.
+
+
+@node Improvisation
+@unnumberedsubsubsec Improvisation
+
+Improvisation is sometimes denoted with slashed note heads. Such
+note heads can be created by adding a @code{Pitch_squash_engraver}
+to the @code{Voice} context. Then, the following command
+
+@example
+\set squashedPosition = #0
+\override NoteHead #'style = #'slash
+@end example
+
+@noindent
+switches on the slashes.
+
+There are shortcuts @code{\improvisationOn} (and an accompanying
+@code{\improvisationOff}) for this command sequence. They are
+used in the following example:
+
+@lilypond[verbatim,quote,ragged-right]
+\new Voice \with {
+ \consists Pitch_squash_engraver
+} \transpose c c' {
+ e8 e g a a16(bes)(a8) g
+ \improvisationOn
+ e8
+ ~e2~e8 f4 fis8
+ ~fis2
+ \improvisationOff
+ a16(bes) a8 g e
+}
+@end lilypond
+
+@seealso
+
+Snippets: @lsrdir{pitches}.
+
+Internals reference: @internalsref{Pitch_squash_engraver} and
+@internalsref{Voice}.
+
+@node Special noteheads
+@unnumberedsubsubsec Special noteheads
+
+@cindex note heads, special
+
+Different noteheads are used by various instruments for various
+meanings -- crosses are used for @q{parlato} with vocalists,
+stopped notes on guitar; diamonds are used for harmonics on string
+instruments, etc. There is a shorthand (@code{\harmonic}) for
+diamond shapes; the other notehead styles are produced by tweaking
+the property:
+
+@lilypond[verbatim,quote,ragged-right,fragment,relative=1]
+c4 d
+\override NoteHead #'style = #'cross
+e f
+\revert NoteHead #'style
+e d <c f\harmonic> <d a'\harmonic>
+@end lilypond
+
+@noindent
+To see all notehead styles, please see @ref{Note head styles}.
+
+
+@seealso
+
+Snippets: @lsrdir{pitches}.