| C | Dm | Em | F | G | Am | B⌀ |
|---|---|---|---|---|---|---|
| I | ii | iii | IV | V | vi | vii |
| Major | Minor | Minor | Major | Major | Minor | Half Diminished |
I’ve just come across this and although I get how to use it, I dont get why it’s the way it is like…
TTSTTTS - I know what this is, where it comes from and how it’s used.
As for the above clip , why are the Maj and mins where they are please. ?
thanks
Rachel…
PS, I’m not sure if I understand my own question yet. ok !!!
Chords are made up of stacked thirds which are, basically, every other note in the scale.
So if you start with the root note, skip a note and take the next note, then skip a note again, and take the next one, that is your basic root triad. In the key of C that would be:
C E G
Now using the TTSTTTS formula we can see that the interval between the C and the E is
T+T = 2 full tones. This interval is a “major third”. Do the same with the E and the G and you get S+T = 1.5 tones. That is a minor third.
So the root chord is a major chord on the bottom, with a minor third on the top.
Repeat this exercise for all the triads in the key.
You’ll see that major chords have a major third followed by a minor third, and minor chords have a minor third interval followed by a major third.
Diminished has two minor thirds.
Cheers,
Keith
Just to add another example to what Keith wrote, take the G major scale (i.e., the usual TTSTTTS formula starting from G).
G A B C D E F♯
Now create triads from each note of the scale:
G-B-D (G)
A-C-E (Am)
B-D-F♯ (Bm)
C-E-G (C)
D-F♯-A (D)
E-G-B (Em)
F♯-A-C (F♯dim)
And as with the key of C, you see the Maj min min Maj Maj min dim pattern.
Note that your original example in the key of C lists the chord built off the seventh scale degree as B⌀. That’s not wrong, but it’s also not completely accurate if you’re just building triads (as the other chords in your example imply) and not seventh chords. If you’re only building triads the chord which results from harmonizing the seventh degree of a major scale is just a diminished triad (e.g. B-D-F), usually notated with the ° symbol (e.g., B°) or with “dim” (e.g., Bdim). It’s when you add a minor seventh to this diminished triad (e.g., B-D-F-A) that you get a half-diminished chord (also notated ø7 and also called a m7♭5 chord). There’s also a diminished seventh chord, which is the diminished triad with a minor third added (e.g., B-D-F-A♭). Such a “fully diminished seventh chord” is usually notated as dim7 or °7.
Ok, I get some of what you’re talking about…
IE D Maj- would be D F# A but at C# would beC# F G# …I hope lol if I stick to 2 full tones then 1.5
Rachel.
| G | Am | Bm | C | D | Em | F#⌀ |
|---|---|---|---|---|---|---|
| I | ii | iii | IV | V | vi | vii |
| Major | Minor | Minor | Major | Major | Minor | Half Diminished |
Because of where they fall .!
ok , does the line Maj, min, min, Maj, Maj, min, half dim - will this work for all major scales 
does the line change for minor scales?
Rachel.
If you mean “any major key” then, yes!
Try it.
Minor keys are a “mode” which, basically, means the same scale pattern is used, but the 6th note of what would have been the major scale becomes the minor scale root.
So the pattern becomes TSTTSTT
Cheers,
Keith
yes lol, I did mean key in both instances. 
Rachel.
As an exercise, you could try to work out the pattern of major, minor, and augmented chords in a minor key by using this pattern like I did for major keys.
Cheers,
Keith
not quite there yet.
Rachel, to add to what @Majik and @J.W.C have shared.
An exercise done relatively early in Justins Practical Music Theory is to work out the major scale notes for each natural note ie not the sharps or flats eg
C D E F G A B C D (added the 2 notes from the next octave for the sake of what is to common in my reply)
G A B C D E F#
D E F# G A B C#
I have done those using the scale interval pattern you understand and the note circle.
Now as the others stated the chords are formed as triads. You make a chord for each note in the scale as they have shown.
In the key of C, the chord formed on the 5th note of the scale, G, is made up of the notes G B and D
Now look at the major scale in G, the chord for the 1st note, the root note is G B D, the G major chord. The pattern for a major chord is 1 3 5, based on the way we form the triad from the notes in the scale
The G chord notes from the C major scale match. Hence the chord on the 5th note of the major scale is a major chord.
Now look at the chord formed on the 2nd note in the C major scale, the notes are D F and A.
Look at the 1st chord in the D major scale, the notes are D F# A, the D major chord.
Now you see there is a difference, the second note in the chord formed with notes from C major scale has a second note that is a semi-tone lower than the D major chord we formed using the D major scale.
A note that is lower by a semi tone is said to be flattened. And it is this flattened third note that gives the minor chord it’s characteristic minor sound. The pattern for a minor chord is 1 b3 5.
If you were to look at the notes in the E major scale you would see the same pattern when comparing the triad build on the E note in the C major scale with the E major chord ie the flattened third note.
You can do this for each note in the scale and would see that the chord follows either the 1 3 5 or 1 b3 5 pattern, until you get to the final 7th note in the scale which is a 1 b3 b5 and named a diminished chord.
Hope that made some sense. In a nutshell you have the pattern for figuring out the notes in the major scale and the pattern for the type of chord for each note in the scale. The first based on scale theory and the second based on chord construction theory.
Hi Rachel - can you please say where you came across it? And why? What were you reading / looking for?
I’m not sure what you mean? …
THis doesn’t correspond with knowing how to use it.
You have had some fantastic knowledge passed your way in this topic and much of it may be beyond your need and your level of understanding just now.
I’m asking questions to try to fathom what you want and need and why and how you hope to use it.
Cheers
Richard
My OP was very badly written. Theres a qustion and example, which have got a little mixed because I wrote it so badly but hey, I did say I’ wan’t sure I understood my own question.
so ignore TTSTTTS now…I’m filling in 30 year old memories lol…
Oh, I agree by the way with what you said. The infomation that @Majik @J.W.C @DavidP have writting is nothing short of fantastic and is proving to be a great help. I have to go back and finish up reading the last couple of posts again today.
so, I’m a binger and yesterday I was reading all manor of theory for about 14 hours, on and off between housework lol.
here’sthe link with that table
This is because I’m finishing up with Grade 1 and starting to look into progression and their construction.
Other links and reading for yesterday.
found this earlier looks pretty good to get into
As for the original table it has
C Dm Em …
some roman numerals
definitin of Maj or Min and dim
I get that the numerals are either upper case or lower case and that denotes Maj or min but.
How are the numerals constructed for that table , what is the theory used to decide upper case or lower. IF there even is one, hence, maybe I dont understand my own question . 
I know the numererals can change so I would like to understand how please.
Rachel.
Hi Rachel,
@Majik @J.W.C @DavidP have answered this but it may not be clear to you as yet, as you’re perhaps trying to understand concepts that require understanding of its building blocks. Absolutely nothing wrong with binge reading lots of theory. I did exactly the same when I started delving into theory. Still do it today 
Its a fascinating endeavour. But structured learning and application is the way forward.
So the initial broad learning order goes Notes 》Intervals 》Scales 》Chords. Understanding AND applying each item will then feed into the understanding AND application of the next item, as they build on each other. Take your time.
Justins Practical Music Theory does this brilliantly, and would highly recommend it. Highly practical too, so will get you on the guitar applying what you learn. And always ask lots of questions as you start to build this ‘pyramid’. 
In answer to your question;
Major and minor chords are determined, defined etc, by the 3rd interval in the chord. If its Major 3rd interval, then its a major chord. If its a minor 3rd interval, its a minor chord.
Cheers, Shane
Rachel,
To add to what Richard and Shane added, I would suggest that you start with Justin’s Practical Music Theory: https://www.justinguitar.com/classes/practical-fast-fun-music-theory-music-theory-course
I am sure that the various sources you read about provided lots of good information. I think essentially they provide many many puzzle pieces. What they may not do is adequately put the pieces together so you can see and make sense of the whole
This is what Justin’s course will do, provide a logical sequence to introduce the puzzle pieces, give you a sense of direction as you work towards building the whole picture.
The first few lessons are free, give you a taste. If that works for you then you would need to subscribe, either USD 9.99 for 6 months access or USD 99.99 for life time access.
I think the framework and flow provided in that will help you to make sense of music theory in a way that is helpful as you continue to learn to play and make music.
Thanks Rachel - this helps to advise you better and more focussed.
And the advice is - come out of that random rabbit-hole and back up so you have daylight and fresh air to breathe. So many sites, with different rates of information thrown out, not all consistent with one another’s approach.
Justin is your man. @DavidP has linked it … the Theory course is what you need.
Look at the first six modules:
I will make several answers, short and long.
Short [1 of 1]
Just as the notes within a major scale follow TTSTTTS so the chords follow a set pattern of Maj-min-min-MAJ-MAJ-min-dim
That happens through a process called harmonising the major scale - stacking notes in thirds until a triad is formed.
Long [1 of 2] taken from this topic: 3rds & Thirds Part B : some theoretical foundations
Harmonising the D Major Scale
We will work through the entire process of harmonising the D Major scale to create all seven chords within the key of D Major.
1] D Major chord = D - F# - A
The interval from Root to 3 is four semitones - this is a Major third so the chord is D Major.
2] E minor chord = E - G - B
The interval from Root to 3 is three semitones - this is a minor third so the chord is E minor.
3] F# minor chord = F# - A - C#
The interval from Root to 3 is three semitones - this is a minor third so the chord is F# minor.
4] G Major chord = G - B - D
The interval from Root to 3 is four semitones - this is a Major third so the chord is G Major.
5] A Major chord = A - C# - E
The interval from Root to 3 is four semitones - this is a Major third so the chord is A Major.
6] B minor chord = B - D - F#
The interval from Root to 3 is three semitones - this is a minor third so the chord is B minor.
7] C# diminished chord = C# - E - G (the awkward diminished chord)
The interval from Root to 3 is three semitones, this is a minor third BUT this is a C# diminished chord, not C# minor. This is due to the distance between its Root and 5 also being a minor third. The six Major and minor chords have an interval of a ‘perfect fifth’ (seven semitones) between their Root and 5. This diminished chord is unique in having a ‘diminished fifth’ interval (six semitones) between them.
Long [2 of 2]
Consider G major - using the major scale formula:
Tone Tone Semitone Tone Tone Tone Semitone or
Whole Whole Half Whole Whole Whole Half
We get these seven notes:
G A B C D E F#
String several octaves together and you have:
G A B C D E F# G A B C D E F# G A B C D E F# G …
The chords in the key, derived from the scale (called the diatonic chords) are found using a process called ‘harmonising the major scale’. These chords will all be triads (three note chords).
Chord I
Root note = G
G A B C D E F# G A B C D E F# G …
Counting:
1, 3, 5 = G, B, D
Chord = G Major
Chord ii
Root note = A
A major scale = A, B, C#, D, E, F#, G#
Counting:
1, 3, 5 = A, C#, E
BUT
C# is not a note in the G major scale (the scale we are harmonising). The only note with a ‘C’ in its name in the G major scale is C natural. And we need to use only the notes in the G major scale when harmonising the G major scale. Therefore, this third note from our counting must be ‘flattened’ to match the notes found in the G major scale.
So, instead of
1, 3, 5 = A, C#, E
G major scale has
1, b3, 5 = A, C, E
Chord = A minor (a flat 3rd note makes a minor chord)
Chord iii
Root note = B
B major scale = B, C#, D#, E, F#, G#, A#
Counting:
1, 3, 5 = B, D#, F#
BUT
D# is not a note in the G major scale (the scale we are harmonising). The only note with a ‘D’ in its name in the G major scale is D natural. And we need to use only the notes in the G major scale when harmonising the G major scale. Therefore, this third note from our counting must be ‘flattened’ to match the notes found in the G major scale.
So, instead of
1, 3, 5 = B, D#, F#
G major scale has
1, b3, 5 = B, D, F#
Chord = B minor (a flat 3rd note makes a minor chord)
Chord IV
Root note = C
C major scale = C, D, E, F, G, A, B
Counting:
1, 3, 5 = C, E, G
Chord = C Major
Chord V
Root note = D
D major scale = D, E, F#, G, A, B, C#
Counting:
1, 3, 4, = D, F#, A
Chord = D Major
Chord vi
Root note = E
E major scale = E, F#, G#, A, B, C#, D#
Counting:
1, 3, 5 = E, G#, B
BUT
G is not a note in the G major scale (the scale we are harmonising). The only note with a ‘G’ in its name in the G major scale is G natural. And we need to use only the notes in the G major scale when harmonising the G major scale. Therefore, this third note from our counting must be ‘flattened’ to match the notes found in the G major scale.
So, instead of
1, 3, 5 = E, G#, B
G major scale has
1, b3, 5 = E, G, B
Chord = E minor (a flat 3rd note makes a minor chord)
Chord vii
Root note = F#
F# major scale = F#, G#, A#, B, C#, D#, E#
Counting:
1, 3, 5 = F#, A#, C#
BUT
Neither A# nor C# are notes in the G major scale (the scale we are harmonising). The only notes with ‘A’ or ‘C’ in their names in the G major scale are A natural and C natural. And we need to use only the notes in the G major scale when harmonising the G major scale. Therefore, this third note and the fifth note from our counting must be ‘flattened’ to match the notes found in the G major scale.
So, instead of
1, 3, 5 = F#, A#, C#
G major scale has
1, b3, b5 = F#, A, C
Chord = F# diminished (a flat 3rd note and a flat 5th note makes a diminished chord)
i = D minor
ii = E diminished
III = F Major
iv = G minor
v = A minor
VI = Bb Major
VII = C Major
Rachel
@sclay Thank you, bleedin obvious now
Suitably chided ,
I will get the Theory but not on top of XMas with aweful exchange rates
I just checked the price (gulp)
Rachel.
Thank you one and all, I feel better now
Rachel.
I’ll get the lifetime Theory soon as I can, I cant do it right now sadly. Next month hopefully.
Thanks again everyone.
Rachel.
Rachael,
I buy the theory course in six month chunks. I’m currently on my second ‘chunk’. I can’t see the need for lifetime access. I’m making my own theory notes as I go through the course. Making notes in your own words is a good way to learn it I think. In future, if I needed to revisit music theory, I would refer to my own notes, rather than re-watch Justin’s lessons.
