User:Romeolz/Isomorphic layouts/Harmonic Table extensions: Difference between revisions

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 = Harmonic Table-ish extensions =
-testing (can you put 2 page titles???)
+These are all the extensions outside "pure HT", which is the mappings where 3/2 and 5/4 are next to the origin like in 12edo HT.
+== Alternate thirds ==
+This encompasses all HT extensions where 5/4 and 6/5 are replaced with some other type of "third", like 9/7 and 7/6, or 16/13 and 39/32. The definition of a "third" is nebulous, so I'm using it to refer to intervals between 240 and 460 cents, depending on context.
+=== Semaphore/Barbados ===
+By splitting the fourth in half we get an interval of about 249 cents. This can be interpreted in many ways, as 7/6, or 15/13, or many others.
+[[File:"HT" (4-3)^(1-2).png|none|thumb|600x600px|An even smaller octave than the augmented layout!]]
+=== Stearnsmic ===
+Splitting 9/2 into 6 equal parts yields an interval very close to 9/7 at about 434 cents. The octave is now already larger than in the hanson layout.
+[[File:"HT" (9-2)^(1-6).png|none|thumb|600x600px|Very close to 2.3.7 just intonation, but octaves are quite a reach.]]
+=== Orwell ===
+Orwell offers good approximations of even 11-limit intervals, using its generator of about 272 cents to split 3/1 into seven. The generator can be 7/6.
+[[File:"HT" (3-1)^(1-7).png|none|thumb|600x600px|A powerful temperament for even 11-limit just intonation, but the layout is quite spread apart...]]