Please Help! I am confused. In the Key of C, the C Dominant 9 Chord scale intervals are 1-3-5-b7-9 and the corresponding notes for that chord line up with the scale intervals, (C- E – G – Bb). wich makes sense, and i understand that that derives from the C Major scale C D E F G A B, with the corresponding numbers to make up the intervals. but when i go to different keys they all have the same intervals (1-3-5-b7-9) but the notes that are in the chord sometimes do not add up with the intervals. (1-3-5-b7-9) for example, in the Key of A, a A Dominant 9 Chord has the exact same interval formula as the other Dominant Chords but the notes for the chord don’t add up to the formula.
1 – 3 – 5 -b7- 9
A – C# – E – G – B
Ex. where there is suppose to be a flat note there is a regular G chord… Does the C# make up for that G chord not being a flat? hmm. would It still be a dominant chord then?
Where I think you are getting confused is the “b” in b7.
A flattened 7th is exactly what it says. It means “flatten” the 7th degree of the scale, regardless of what the note already is, we still need to flatten it.
If it’s a natural note then it will become a flattened note.
If it’s sharp then it will become a natural note.
In the key of C we have the scale notes:
C-D-E-F-G-A-B
B is the 7th so a flat 7th will become Bb.
In the key of A we have the scale notes
A-B-C#-D-E-F#-G#
G# is the 7th so the flat 7th will become G.
Adom9 therefore = A-C#-E-G-B
The C# is simply the 3rd scale degree in A major.
Always number the notes in a key from 1 to 7. These will be your scale degrees from which you can use scale formulas.
All scale and chord formulas are with reference to the major scale. Doesn’t matter what the chord type, if it’s a minor chord, the formula is still with reference to the major scale. Look again at the notes in A major and compare the notes and formula for Am9.
Am9 = 1-b3-5-b7-9 – A-C-E-G-B
This chord has the same formula as the dom7 but with a b3. We know that the 3rd of A major is C#. If we flatten it, it becomes C.
Let’s look at one more. Key of Gb … a horrible bunch of notes 🙂
Gb major scale: Gb-Ab-Bb-Cb-Db-Eb-F
Let’s say the chord is a dominant 7(b9)
This chord is a dom7 with a b9.
Formula: 1-3-5-b7-9
Chord notes: Gb-Bb-Db-Ebb-Fb
Ebb and Fb look weird and wrong. Technically they are the correct terms to use. Many musicians will call them exactly that, especially music readers.
Most of us (myself included) willd just call them D (Ebb) and E (Fb). But technically, this wouldn’t be correct.
In summary.
1: Get the notes for the major scale.
2: Number them from 1 to 7
3: Apply the formula to those notes.
