A tuning which transcends both the small-integer ratios of just-intonation, and the logarithmically equal "steps" or divisions of Equal Temperament.
The well-temperaments may be considered a subset of these, although in modern usage these nj-net scales are also frequently non-octave.
For examples, see Jonathan Harvey's 1984 classic Mortuos Plango Vivos Voco, Jean Claude Risset's classic computer piece Inharmonique, and many pieces by Brian McLaren.
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