Numerical sight-singing

An alternative to the solfege system of sight-singing[?], this system numbers the [diatonic scale] with the numbers one through eight (or, alternately, one to seven, with the octave again being one.

Scale degree	Number	Solfege Syllable
Unison, Octave	"one"	Do
Augmented unison	"sharp one", or just "one"	Di
Minor second	"flat two" or just "two"		Ra
Major second	"two"		Re
Augmented second	"sharp two" or just "two"	Ri
Minor third	"flat three" or just "three"	Mé
Major third	"three"	Mi
Perfect fourth	"four"	Fa
Augmented fourth	"sharp four" or just "four"	Fi
Diminished fifth	"flat five" or just "five"	Se
Perfect fifth	"five"	Sol
Augmneted fifth	"sharp five" or just "five"	Si
Minor sixth	"flat six" or just "six"	Le
Major sixth	"six"	La
Augmented sixth	"sharp six" or just "six"	Li
Minor seventh	"flat seven" or just "seven"	Te
Major seventh	"seven"	Ti

In this system, 1 is always the root or origin, but the scale being represented may be [major], [minor], or any of the diatonic modes[?]. Accidentals (sharps and flats outside the key signature) are noted with a + or - when the numbers are written, but are often skipped when they are spoken or sung.

For example, one might sing "one, three, five, three, one" for a [major triad], but a [diminished triad] might be either "one, three, five, three one" or "one, flat three, flat five, flat three, one", depending on the student and the speed of the piece.

There is a pedagogical[?] debate about the merits of this system as compared to solfege: it holds an advantage in that no time is spent teaching the singers the system, and no memorization is required, but it is less precise.