Pairwise well-formed modes are investigated as substitutions on words over a three-letter alphabet. Motivating examples are the major and minor modes, here described in terms of the substitutions $a\mapsto ac,b\mapsto ba,c\mapsto cab$ and $a\mapsto ab,b\mapsto ca,c\mapsto bac$. Pairwise well-formedness is investigated through the inspection of the two-letter-mergings of a substiution, namely concatenations with letter insertions from the right and letter projections from the left. The appropriate generalizations of the two mentioned examples are the plain and twisted kaleidoscope substitutions. Four of their mergings turn out to be Sturmian morphisms with interesting interdependencies. The diatonic mergings are musically related to the medieval modes, which are fifth-generated. The syntonic mergings are third-generated and provide a common neutral anchor for the major and minor modes. The paper thus provides a new proposal in order to integrate the diatonic side of harmonic tonality with its triadic aspects, which we characterize as its syntonic side.

研究成对格式良好的模式，作为对三个字母的单词的替换。动机示例是主要和次要模式，在此以替代方式进行描述$\mathrm{一种}\mapsto \mathrm{一种}C，b\mapsto b\mathrm{一种}，C\mapsto C\mathrm{一种}b$ 和 $\mathrm{一种}\mapsto \mathrm{一种}b，b\mapsto C\mathrm{一种}，C\mapsto b\mathrm{一种}C$。通过检查一个替换的两个字母合并来研究成对的格式正确性，即从右侧插入字母并从左侧插入字母投影的连接。对上述两个示例的适当概括是普通的和扭曲的万花筒替换。他们的四个合并结果是具有有趣的相互依赖性的Sturmian射态。的全音阶mergings是音乐相关的中世纪模式，即第五生成。该谐振合并是第三代合并的，并为主要和次要模式提供了通用的中性锚。因此，本文提出了一个新的建议，以便将谐波音调的全音阶方面与其三重音方面进行整合，我们将其表征为其谐音方面。