Editing Octatonic scale (section)

===Beta chord===
<!--[[Beta chord]] redirects directly here.-->
{{Image frame|content=<score sound="1">
{
\override Score.TimeSignature #'stencil = ##f
\relative c' {
  \clef treble \key c \major
  <cis e g bes c>1 <cis e g c> <cis g' c>
} }
</score>|width=300|caption=A beta chord on C{{music|#}}, with two reduced versions}}

The beta chord (β chord) is a five-note chord, formed from the first five notes of the alpha chord (integers: 0,3,6,9,11;{{sfn|Honti|2007|loc=305}} notes: C{{music|#}}, E, G, B{{music|b}}, C{{music|natural}}). The beta chord can also occur in its reduced form, that is, limited to the characteristic tones (C{{music|#}}, E, G, C{{music|natural}} and C{{music|#}}, G, C{{music|natural}}). Forte number: 5-31B.

The beta chord may be created from a [[diminished seventh chord]] by adding a diminished octave. It may be created from a major chord by adding the sharpened root (solfege: in C, di is C{{music|#}}: C{{music|sharp}}, E, G, C{{music|natural}}),{{sfn|Anon.|1977|loc=12}} or from a diminished triad by adding the root's major 7th (called a diminished major 7th, or C#{{music|diminished}}<sup>Maj7</sup>. The diminished octave is inverted creates a minor ninth,{{clarify|date=August 2021|reason=Mangled grammar, incomprehensible.}} creating a C<sup>({{music|flat}}9)</sup> chord, a sound commonly heard in the V chord during an authentic cadence in a minor key.{{citation needed|date=August 2021}}