https://alonetone.com/vaisvil/tracks/ts-eliot-preludes-2—pythagorean-tuning
This was realized by composing Natalie’s part with a keyboard and pianoteq in Pythagorean tuning - exporting the voice, using Melodyne to retune Natalie to Pythagorean tuning and then composing the accomplishment using the pianoteq classical guitar preset in Pythagorean tuning - minor touch ups for both parts were done - the DAW was Cakewalk by Bandlab and my venerable Breverb the only effect added.