Hi-lo notation
Hi-lo notation is for naming chord voicings. It applies to all tunings, even conventional ones like 12-edo or meantone. It allows arrangers, composers and theorists to discuss specific voicings with much more accuracy than the conventional 1st inversion, 2nd inversion, etc. nomenclature.
- C E G = C or C close
- C G E = Chi3 (because the 3rd is an 8ve higher than in the close voicing)
- G C E = Clo5 (aka 2nd inversion)
- E G C = ChiR (R stands for root) aka 1st inversion
- E C G = Clo3 (also 1st inversion)
- G E C = ChiRlo5
When there are multiple high or low notes, the terms "hi" and "lo" are only used once:
- C G E B = CM7hi37
- G Bb C E = C7lo57
"Add" is used for duplicated notes:
- C E G C = Cadd8
- G C E G = Caddlo5
- G C E G C = Cadd8lo5
- C E G E = Caddhi3 or Cadd10
- C C E G = CaddloR or possibly Chi35add8
This doesn't conflict with the usual use of "add" in chord names:
- C E G D = Cadd9
- C E G C D = Cadd89
- C D E G = Caddlo9 or Cadd2
- D C E G = Caddlo2
"No" is used as usual to omit notes, as in C9no5. The 4 words are used in this order: no - hi - lo - add - hi - lo. First omit notes, then move notes higher, then move notes lower, then add notes, then add high notes, then add low notes. Following this order removes any ambiguity:
- Chi3add8 = C G C E
- Cadd8hi3 = C E G C E
- Caddhi38 = C E G E C
The common open chords of a guitar:
- C major: x32010 = C E G C E = Cadd8hi3
- D major: x00232 = A D A D F# = Dhi3add8lo5
- E major: 022100 = E B E G# B E = Eadd8loR5 or possibly Ehi3add8hi58
- G major: 320003 = G B D G B G = Gadd8hi38 or possibly Glo5add8loR3
- A major: 002220 = E A E A C# E = Ahi3add8hi5lo5
To find the number of voices in a chord, start with the obvious: a triad has 3, a tetrad has 4, etc. Then subtract the "no" notes and add the "add" notes. For example, A7no5hi3add8 has 4 (tetrad) - 1 (no 5th) + 1 (add 8ve) = 4.
For more examples, see Kite Guitar Chord Shapes (downmajor tuning).
Notating chord progressions
There are sometimes two possible names for a voicing, depending on what one considers the "home octave" to be. As we saw, C C E G can be either CaddloR or Chi35add8. This ambiguity can be removed by designating one note in a specific octave as "the" tonic, then naming all other notes relative to that tonic. Unlike octave numbers which only increase when going from B up to C, the hi-lo categories only change in the region of the tonic. This has the advantage that transposing to a new key won't change the hi-lo categories.
| SPN names | D2 | E2 | F#2 | G2 | A2 | B2 | C3 | D3 | E3 | F#3 | G3 | A3 | B3 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| hi-lo names | loD | loE | loF# | G | A | B | C | D | E | F# | hiG | hiA | hiB |
Chord progressions can be written out as e.g. Cadd8 - loAmhi3add8 - Dm7 - loG7hi3. The entire 4-part harmony can be deduced note-for-note from this. Here are the notes, where the lower octave uses underlined letters and the upper octave uses lower-case letters:
- C E G c
- A E A c
- D F A c
- G D F B
This works with relative notation as well: Iadd8 - loVImhi3add8 - IIm7 - loV7hi3.
Naming the roots as hi or lo almost allows us to reduce a barbershop tag to a mere succession of chords. However voices sometimes coincide or cross. See Kite Guitar Translations by Kite Giedraitis#Barbershop tags
Hi-lo notation was invented by Kite Giedraitis.