Chord progressions for a scale

It's actually not as complicated as we sometimes try to make it out. This, however, is a bit of an oversimplification.

The notes in the scale of C major are C-D-E-F-G-A-B-C, and you build your chords by taking every other note - so the notes in a chord of C are C, E and G, and the notes in Dm are D, F and A. You'll notice there is a four fret gap from C to E in C major and a three fret gap from D to F in Dm and that is how we determine whether a chord is major or minor

Why is a I-IV-V sequece C-F-G7 and not C-Fm-Gm? A chord of Fm requires the notes F, a three fret step to Ab and C, and a chord of Gm requires the notes G, a three fret step to Bb and D. You'll notice that Ab and Bb don't exist in the scale of C we wrote out up top; so we have F and G major chords.

Why is there a 7 in the dominant 5th? The real highly theoretical stuff about it is way beyond me, but I'm sure Noteboat will be able to give us all chapter and verse on it. Suffice to say that, in a G7->C (perfect) cadence, the root note (G) resolves by stepping down via the 7th (F) to the 3rd of the tonic chord (E in the C major chord) and the 3rd in the dominant (B in the G7 chord) resolves to the root note in the tonic chord (C in C); the particular sound of a 7 chord being caused by the tritone from the 3rd (B in the G7 chord) to the 7th (the F).

This works in minor keys too, the dominant chord in Am is still E7, a major chord with a G# in it.

A :-)

This is why I failed music appreciation in the 8th grade. I know I should be able to understand this but reading Alans reply almost made my head explode :? I can do complex math equations; I got an A in college calculus. Why does music theory make me want to scream?

This is why I failed music appreciation in the 8th grade. I know I should be able to understand this but reading Alans reply almost made my head explode :? I can do complex math equations; I got an A in college calculus. Why does music theory make me want to scream?

Because it's Arithmetic and not Mathematics? :wink:

It's actually not as complicated as we sometimes try to make it out.

:lol: :lol: :lol:
I know I should be able to understand this but reading Alans reply almost made my head explode :?
+1, I read this like 5 times before I think I kind of understood it.

When I first went into theory, I built some web pages to help me remember. I made one that might help you to understand a little easier - http://freenet-homepage.de/greybeard/Modes.htm

Thanks for that link! It helped out a bit in how things relate to each other!

When I first went into theory, I built some web pages to help me remember. I made one that might help you to understand a little easier - http://freenet-homepage.de/greybeard/Modes.htm

I tried to look at your charts but this little voice kept saying "look away look away". Then I felt that pressure building in my brain and the whole page became a blur. Maybe I should try that music appreciation coarse again?

You're clearly destined to play jazz for the rest of your days

A :D

You might find this approach a little too easy, but it may also clear up your head enough to give you a fresh start:

https://www.guitarnoise.com/lesson/the-power-of-three/

It may not seem like it right now, but a lot of this stuff becomes second nature through repetition. Trouble is, in most of our lives there is no reason to reinforce the learning and so it often is a matter of learning and relearning and relearning. Take a little time and write things out and test yourself. The more you can make it of a practical and useful nature to yourself, the quicker it will sink in.

Hope this helps.

Peace

Thank you guys, I really should do some simple arithmetics before asking initial question! :oops: What I still don't understand is where that 7 comes from. And, actually, if we use those chords to construct a progression in a given key, when can we use other chord forms like 9th or 13th? Okay, okay, I'll know I should buy a good theory book 8)

Thank you guys, I really should do some simple arithmetics before asking initial question! :oops: What I still don't understand is where that 7 comes from.

Here are a couple of tables that people have found useful:
Notes by scale degree Notes by name (in C)
1 2 3 4 5 6 7 8 C D E F G A B C Chord no. Chord name.
-------------------------------------------------------------------------
1 3 5 C E G I C major
2 4 6 D F A ii D minor
3 5 7 E G B iii E minor
4 6 8 F A C IV F major
5 7 9 G B D V G major
6 8 10 A C E vi A minor
7 9 11 B D F vii° B diminished


Now, here's the same table, harmonising each note in 7ths, i.e. with four notes per chord:

Notes by scale degree Notes by name (in C)
1 2 3 4 5 6 7 8 C D E F G A B C Chord no. Chord name.
-------------------------------------------------------------------------
1 3 5 7 C E G B Imaj7 Cmaj7
2 4 6 8 D F A C iim7 Dm7
3 5 7 9 E G B D iiim7 Em7
4 6 8 10 F A C E IVmaj7 Fmaj7
5 7 9 11 G B D F V7 G7
6 8 10 12 A C E G vim7 Am7
7 9 11 13 B D F A viim7b5 Bm7b5


They are the same except for the last note, the seventh. Note that they form different kinds of sevenths depending on the scale degree. The I and IV are maj7 while the V is a dominant 7th.

Now, while jazzers often use four-note chords all over the place, in general, for rock, pop and folk, that is too much. Especially the maj7 is too radically different in tone from the major and is only used occasionally for flavour. The min7 are often used though because they sound a little less "minor" thatn

The dom7, the V, however is special. To put it simply, it dominates. How so? Well, it virtually forces you to hear the note a 4th above as the key centre. Including a G7 makes you want to hear a C, a "resolution". Why is that?

Well, the new note added to G major (G-B-D) to make a G7 is an F. The interval between the B and the F is called a tritone (AKA b5, #4, diabolus). The tritone B-F is "dissonant" (tense, uncomfortable). Move each note a semitone (half step), B up to C and F down to E and we get the C-E major 3rd which is "consonant" (pleasant, stable).

This resolution from the tense V7 to the stable I is characteristic of all modern music, classical, jazz or popular.
And, actually, if we use those chords to construct a progression in a given key, when can we use other chord forms like 9th or 13th?

We can extend the chords further, adding the 9th (2), the 11th (4) or the 13th (6). These are used for additional colour but do not change the fundamental character of the chord like 7th do.

True 9th and 13th chords (and maj9, maj13) , where the 9 and 13 are stocked on top of the dom7 or maj7 chord are virtually only used in jazz (or classical music). They are complex and require a very clean sound to be heard properly.

Like a rolling stone uses the first five chords of the C major scale. C, Dm, Em, F and then G instead of G7... Maybe that's why it sound so cool and you get a totally different feeling than if you replace the G with G7. On the other hand, playing Dm7 instead of Dm doesn't make a difference, the song sounds just as good (in my ears, that is :)). Just something I found interesting. :)