Note for the manual

[Steve D]

For manual, 2.7 series, section 6.2.2, "Octave check"

Comment and suggestion--
The part of this section that explains \octave is somewhat difficult to
understand. It might be helpful, especially for beginners, to state that
"\octave a'" and other \octave checks produce no visible output in the
score, but that it is instead strictly a method to verify whether the
pitch that is specified with \octave would be (in \relative mode and if
it indeed were notated) at the absolute location indicated by the
single-quote(s) or comma(s) following that pitch.

One of the confusing things about the example is that, if one were to
think that \octave a' actually produced a notated A in the score, then:

\relative c' {
  e
  \octave a'
  \octave b'
}

would seem confusing, because it would seem that, since the expression
is in relative mode, that \octave b' is checking to see whether the B
that will be notated (if \octave b' did indeed produce output visible in
the score) is actually in the same octave (within an interval of a
fourth higher or lower) as the a' that came before it, when in fact both
\octave checks refer to the "e" that precedes them.

Best wishes,

-sd
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