We need a system that differentiates between function and quality, hence why we have Leadsheet Notation for quality and Roman Numeral Analysis for function.
Definitions of new/unfamiliar terms for leadsheet notation:
What is the difference between an add 6 chord and an inverted minor seventh chord? (Ex: C^6 and Am7/C?)
What do we sub out in a sub chord?
Why is leadsheet notation important for our class?
Slash Chords
This is how we mark inversions for lead sheet notation (both triads and 7th chords).
Fro slash chords, here is an example: (Amin7/C) The A in this example represents the Tonic of the chord (the root). the “min7” tells us that this is a minor minor seventh chord (The quality of the Chord), and the C below tells us the bottom note (the bass). In this case, Amin7/C is a 1st inversion Amin7 seventh chord.
Unlike Roman Numerals and Chord Identification Notation (Mm7,MM7,dim7,etc.), the “7” from the quality of the chord description does not change to represnt the inversion. (from our example, we are reffering the the “7” in our Amin7/C). The “7” tells us that the chord is a seventh chord. The slash chord and note below tells us what the inversion is. If we were to transfer our example (Amin7/C) into our other quality identification system, it would look like: mm6/5, a minor minor chord seventh chord in first inversion.
A triad can be summed up by a single symbol, such as a lead-sheet chord symbol. A lead sheet symbol includes information about both root quality, as well as which pitch class occurs in the lowest voice (called the bass regardless of who is singing or playing that pitch).
A lead-sheet symbol begins with a capital letter (and, if necessary, an accidental) denoting the root of the chord. That letter is followed by information about a chord’s quality:
Finally, if a pitch class other than the chord root is the lowest note in the chord, a slash is added, followed by a capital letter denoting the pitch class in the bass (lowest) voice.
A C-major triad’s lead-sheet symbol is simply C. A C-minor triad is Cm. A D-sharp-diminished triad with an F-sharp in the bass is D#dim/F#. And so on.