Interval of equivalence: Difference between revisions

Undoing last two edits (the term "formal octave" is not limited to Scala, other software programs and other people also use it)
Tag: Manual revert
Non-octave equivalence: equave should not exclude octave
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== Non-octave equivalence ==
== Non-octave equivalence ==
When the interval of equivalence is specifically not an octave, it is called the '''equave''' (a portmanteau of "equivalence" and "octave") or '''formal octave'''<ref>Op de Coul M. ''Scala help'' https://www.huygens-fokker.org/scala/help.htm</ref>.
When the interval of equivalence is allowed to be a non-octave interval, it is called the '''equave''' (a portmanteau of "equivalence" and "octave") or '''formal octave'''<ref>Op de Coul M. ''Scala help'' https://www.huygens-fokker.org/scala/help.htm</ref>. While the octave is the predominant interval of equivalence in most musical traditions, alternative equivalence intervals have been explored. A famous example is the [[tritave]] in [[Bohlen–Pierce]] and related systems.
While the octave is the predominant interval of equivalence in most musical traditions, alternative equivalence intervals have been explored.
A famous example is the [[tritave]] in [[Bohlen–Pierce]] and related systems.


=== Pseudo-octave ===
=== Pseudo-octave ===
{{Wikipedia|Pseudo-octave}}
{{Wikipedia|Pseudo-octave}}
A '''pseudo-octave''' is an interval that is not exactly [[2/1]], but close enough to still be treated as an octave.
A '''pseudo-octave''' is an interval that is not exactly [[2/1]], but close enough to still be treated as an octave.


[[Stretched tuning|Stretched or compressed tunings]] may be said to have pseudo-octaves, as do many non-octave scales.
[[Stretched tuning|Stretched or compressed tunings]] may be said to have pseudo-octaves, as do many non-octave scales. For example, the [[Carlos Beta]] scale has a pseudo-octave of 1212.8{{c}} at 19 steps.
For example, the [[Carlos Beta]] scale has a pseudo-octave of 1212.8{{c}} at 19 steps.


== Examples ==
== Examples ==