128/121
128/121, the undecimal diatonic semitone, or octave-reduced 121st subharmonic, is an 11-limit semitone with a value of roughly 97.36412 cents. As the name "undecimal diatonic semitone" suggests, it acts as the diatonic counterpart to the 1089/1024, with the two intervals adding up to a 9/8 whole tone.