Are there solfege syllables for diminished and augmented imperfect intervals?

Question

Sometimes it is necessary to name notes and intervals differently based on how they are functioning and I was curious if this idea caired over to solfege.

For example, the notes of a C^o7 are C, Eb, Gb, and Bbb. The C would be Do, the Eb would be Me, and the Gb would be Se. Would there be a better way to describe the Bbb then La which would represent A, the enharmonic equivalent of Bbb?

Answer 1

This depends in large part whether we're talking about "fixed do" or "movable do" solfege, so I'll answer from each perspective:

Movable Do

In movable-do solfege, the syllables mark the scale degree rather than the absolute pitch of the note, so the syllables used will vary depending on the key in which the chord appears. In practice, diminished seventh chords will almost always be found as a vii°7, so the top note of the diminished seventh is actually a minor sixth relative to the tonic (do). Thus, it would take the syllable "le".

For example: C°7 in practice is likely to appear in the key of Db, and since Db is then "do", the notes of the chord (C, Eb, Gb, Bbb) would be "ti", "re", "fa", and "le", respectively. You'll find that other common roots for diminished sevenths (sharp second, sharp sixth) also work out in a similar way without requiring any new solfege syllables.

Fixed Do

Traditionally, in fixed-do solfege each syllable simply names a note without regard to accidentals, so B, Bb, and Bbb would all be named "ti" (as would B sharp and double-sharp). In more recent practice, there are some systems designed to add chromatic names to fixed-do solfege. While I've never personally used any such system, Wikipedia gives an overview of a few different variants, with Bbb corresponding to "sef", "taw", or "tu", depending on which scheme is in use.

Answer 2

My students and I just had this discussion in spelling fully diminshed seveths. We think the diminished seventh should be TA. Here's why, the flatted seventh is TE, if we make it a double-flatted seventh it makes sense to use TA. It stays in the the TI family and gives a direction towards LA.

Answer 3

Only in the absolute spelling (fixed Do) the syllables doremi are corresponding to the cdefg.

But in the relative spelling this tetrad c-eb-gb-bb is the VIIdim of Db (major or minor) and will be spelled ti-re-fa-le (or: se,ti,re,fa,le in Db-minor).

The seven syllables normally used for this practice in English-speaking countries are: do, re, mi, fa, sol, la, and ti (with sharpened notes of di, ri, fi, si, li and flattened notes of te, le, se, me, ra).

https://en.wikipedia.org/wiki/Solmization

also see:

Tonic sol-fa (or tonic sol-fah) is a pedagogical technique for teaching sight-singing, invented by Sarah Ann Glover (1785–1867) of Norwich, England and popularised by John Curwen who adapted it from a number of earlier musical systems. It uses a system of musical notation based on movable do solfège, whereby every tone is given a name according to its relationship with other tones in the key: the usual staff notation is replaced with anglicized solfège syllables (e.g. do, re, mi, fa, sol, la, ti, do) or their abbreviations (d, r, m, f, s, l, t, d). "Do" is chosen to be the tonic of whatever key is being used (thus the terminology moveable Do). The original solfège sequence started with "Ut" which later became "Do".

https://en.wikipedia.org/wiki/Tonic_sol-fa