Any other distribution will result unquestionably in a grievous lack of relationship between registers:
| To be avoided: | etc. |
If one tone quality is to be enclosed, it must be between two different timbres:
| Good: | etc. | |
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It is possible to lend four distinct timbres to a chord in widely-divided four-part harmony, though such a chord will possess no uniformity in colour; but the higher the registers of the different instruments are placed, the less perceptible becomes the space which separates them:
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