www.musictheory.net and then the piano theory books; Alfred's Theory 1 - 3. Every piano student in the last 50 plus years started out on Alfred's books. I do recommend you start with one of the "Pure" theory books, not something written specifically for the bass. Music theory is music theory - generic to all instruments.
http://www.guitar-chords.org.uk/chords-key-c.html will pull up the notes for just about any scale and then give you the chords made from that scale.
Yep chords are made from the notes of the scale. Every other one. So if you stack the notes of a scale you get the chords that harmonize that scale. As we play chord tones understanding this (it's called stacking 3rds) helped me pull everything together. Here is an example:
C Major Scale stack in 3rds (every other note) = the notes and chords made from the C major scale:
Code:
Notes Degree Spelling Chord name Function
C R CEGB R-3-5-7 Cmaj7 I (tonic)
D 2 DFAC R-b3-5-b7 Dm7 ii
E 3 EGBD R-b3-5-b7 Em7 iii
F 4 FACE R-3-5-7 Fmaj7 IV (subdominant)
G 5 GBDF R-3-5-b7 G7 V (dominant)
A 6 ACEG R-b3-5-b7 Am7 vi
B 7 BDFA R-b3-b5-b7 Bm7b5 vii (diminished)
For some reason this never travels well to the Internet - get the stacks lined up.
Why is the D chord minor? If you compare the DFAC to the notes in the D major scale the D major scale will have an F# and a C#. Your DFAC has the 3 and 7 flatted for a spelling of R-b3-5-b7 and that spelling makes a Dm7 chord. All minor chords will have a b3. All major chords will have a natural 3. Stacking the scale in 3rds automatically build the correct major, minor and diminished chords for that scale. That was a very big WOW for me and was the Rosetta Stone I was looking for.
Do a Google using this key word -- WWHWWWH -- that will send you to several papers on the Major scale and how it is formed. The following chart helped me see the entire Major and Natural Minor scale, i.e the big picture on one sheet of paper:
Major Scale Chart
C D E F G A B...............Notice the C scale has no Sharps
G A B C D E F#.............and the G scale has one, the F#
D E F# G A B C#...........and the D scale keeps the F# and
A B C# D E F# G#.........adds the C#. Then the A scale keeps
E F# G# A B C# D#.......everything and adds the G#. See how
B C# D# E F# G# A#.....it builds on it's self.
F# G# A# B C# D# E#
C# D# E# F# G# A# B#
F G A Bb C D E.............Look what happens with the flat scales
Bb C D Eb F G A...........F has one the Bb, then the Bb scale keeps
Eb F G Ab Bb C D.........it's self and adds the the Eb. Same thing
Ab Bb C Db Eb F G.......the sharp scales did...
Db Eb F Gb Ab Bb C
Gb Ab Bb Cb Db Eb F
Cb Db Eb Fb Gb Ab Bb
Memory pegs:
See God Destroy All Earth By F#irey C#haos. Order of the scales with sharps.
Fat cats go down alleys eating birds. Order of the sharps.
Farmer brown eats apple dumplings greasily cooked. Order of the scales with flats.
The key signature is showing three sharps. What scale has three sharps? C has none, G has one, D has two, A has three. Which sharps? Fat Cats Go so the A major scale has three sharps, F#, C# and G#. Using these memory pegs eliminates the need for the above chart. Learn the pegs - that fish thing.
Natural Minor Scale Chart
A B C D E F G ................Notice how the 6th column of the
E F# G A B C D................Major scale becomes the 1st column
B C# D E F# G A..............in the minor scale and how the 7th
F# G# A B C# D E............column of the Major scale is now the
C# D# E F# G# A B..........2nd column in the minor scale. And
G# A# B C# D# E F#........yep, the 1st column in the Major scale
D# E# F# G# A# B C#......is now the 3rd column, etc. etc.
A# B# C# D# E# F# G#....Ask your self why? Hint, think relative minor.
D E F G A Bb C
G A Bb C D Eb F
C D Eb F G Ab Bb
F G Ab Bb C Db Eb
Bb C Db Eb F Gb Ab
Eb F Gb Ab Bb Cb Db
Ab Bb Cb Db Eb Fb Gb
Opps, ran out of space, that's all the forum will allow. That should keep you busy till you get back.