A schismatic temperament is a musical tuning system that results from tempering the schisma of 32805:32768 (1.9537 cents) to a unison.
Ellis's "skhismic temperament"[1] instead uses the note eight fifths below C, F♭-- (384.36 cents playⓘ), the Pythagorean diminished fourth or schismatic major third.
This places them well outside the span of a single diatonic scale, and requires both a larger number of pitches and more microtonal pitch-shifting when attempting common-practice Western music.
Historically significant is the eighth-schisma tuning of Hermann von Helmholtz and Norwegian composer Eivind Groven.
[citation needed] Groven built an organ internally equipped with 36 tones to the octave which had the ability to adjust its tuning automatically during performances; the performer plays a familiar 12-key (per octave) keyboard and in most cases the mechanism will choose from among the three tunings for each key so that the chords played sound virtually in just intonation.
[citation needed] Mark Lindley and Ronald Turner-Smith argue that schismatic tuning was briefly in use during the late medieval period.