Chords & roman numerals

[D-Tuned]

I made a jamming video with help from SonicVisualiser, it scrolls the chord names and diagrams as the song progresses. I show the chord roman numerals too, the catch being that sometimes I show all three but sometimes only one ...which helps with the learning. Pretty clear so long as standard chords with their numerals are used but here comes a question:

In C#m the C#m chord is the "i" numeral, but what if the piece has a C# major in it? It seems to me that that is no longer the "i" chord and the dilemma (for me at this point at least) deepens when the my video seeks to challenge the subject to play the "i" chord in which case no one could be expected to play a C#.

Rephrased, how to use roman numerals to label off-standard chords and how to come up with the correct chord when seeing such labels?

[magicalex]

You would use an uppercase 'I' to represent C#major in the key of C#minor.

[D-Tuned]

Yet another freakin' paradigm shift for me but thank you. I would've thought that one could use only a single set of roman numerals in a key, so if I had to guess I would have guessed iM meaning a minor first but major

[magicalex]

Just to be clear, uppercase denotes major, lowercase denotes minor irrespective of key.

[D-Tuned]

Yes, so that in the key of C#m the 'standard' chords with roman numerals would be:

Code: Select all

i    C#m
ii   D#dim
III  E
iv   F#m
v    G#m
VI   A
VII  B

I can see myself making a jamming video in which the C# diagram that drifts by is labeled as a both a C# and as a I. But when I do the dirty move of using only two or only one of its designators and show just I ...I'm not sure it's gonna fly. If it is as you say and it is a widely held practice then yes. I'm not calling you on it, I have no clue, or I wouldn't have asked

[tavasti]

Code: Select all

ii   D#dim

That is incorrect, ii would D#min, ii° is D#dim

[D-Tuned]

Code: Select all

ii   D#dim

That is incorrect, ii would D#min, ii° is D#dim

Thanks, there goes yet another one where I managed to pile my fingers up my stack all the way to the armpit. Now I have to edit all the 2nds & 7ths in my chords cheatsheet because I called the major scale ending diminished chords just vii's as well. Not happy ...but it will heal