Indiana University

Piano Technology

Piano Shop Resources

1/7 Comma Well Temperament

  • Tune A4 to fork. The number 4 indicates notes in the octave above middle C4.
  • Tune A3 to A4. The number 3 indicates notes in the octave below middle C4.
  • Tune F3 to A3 making a wide 3rd with 4 beats per second.
  • Tune C4 to F3 making a narrow 1/7c 5th beating around 1 beat per second.
  • Tune D4 to A3 making a wide 1/7c 4th beating around 1� beats per second.
  • Tune G3 to C4 and D4. Make a wide G3C4 1/7c 4th and a narrow G3D4 1/7c 5th.
  • Tune E4 making a narrow 1/7c A3E4 5th. The C4E4 3rd should beat around 6 beats per second.
  • Tune B3 making a wide 1/7c B3E4 4th. The G3B3 3rd should beat around 4� beats per second.
  • Tune C3 to C4 making a good octave with a wide C3F3 4th and a narrow C3G3 5th.
  • Tune D3 to D4 making a good octave with a wide D3G3 4th and a narrow D3A3 5th.
  • Tune E3 to E4 making a good octave with a wide E3A3 4th and a narrow E3B3 5th.
  • Tune F#3 making a perfect F#3B3 4th.
  • Tune C#4 making a perfect F#3C#4 5th.
  • Tune Bb3 making a perfect F3Bb3 4th.
  • Tune Eb4 making a perfect Bb3Eb4 4th.
  • Tune G#3/Ab3 making a wide G#3C#4 4th and a narrow Ab3Eb3 5th. This should split G#Ab between E3 and C4.
  • Tune F4,F#4,G4,G#4 etc. checking 4ths,5ths and octaves.
  • Tune Eb3,C#3,B2,Bb2 etc. checking 3rds, 4ths, 5ths and octaves

The results look like this with six 1/7 comma tempered 5ths. Four perfect 5ths and two equal tempered 5ths. 1/7 comma 5ths are narrow by around 1 beat per second. 1/7 comma 4ths are wide by around 1� beats per second.

F 1/7 C 1/7 G 1/7 D 1/7 A 1/7 E 1/7 B 0 F# 0 C# = G# = Eb 0 Bb 0 F

Cents and Frequency table for 1/7 comma Well Temperament