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In the manual I am reading it states Primary Chords of a key are identified by the Roman Numerals I, IV and V. It goes on to state that in the Scale of C there are 3 Primary or Major Triads: C, F and G. Further, that they consist of the root, a major 3rd and a perfect 5th.

This is confusing. The manual goes from a 1,3,5 sequence to a 1,4,5 sequence. I don't get it. Your comments please.

Thank you.

I=CEG (root=C, major 3rd = C-E, perfect 5th = C-G)
IV=FAC(root=F, major 3rd = F-A, perfect 5th = F-C)
V=GBD (root=G, major 3rd = G-B, perfect 5th = G-D)

does this make sense?

Well, a triad is a chord of three tones a third apart, i.e., C E G
D F A
E G B
F A C so a triad has three tones built on the interval of thirds.

A scale is a ladder of tones, i.e., C D E F G A B C

C = I
D = II
E = III
F = IV
G = V
A = VI
B = VII

Thus a chord (triad) built on C is C E G or a I chord.
A chord (triad) built on F is F A C or a IV chord

A chord (triad) built on G is G B D or a V chord

The root refers to the starting tone of the chord as the root of C E G is C; F A C is F; G B D is G

That's a beginning. But no matter what key is used the name of the key is NUMBER 1. Example: The starting key of the scale in C is C; in F it is F; in A it is A. So A is 1, B is 2, C# is 3 and so forth. I hope this helps.

Thanks to the above. I think I got it .... somewhat. Another quick question. What is the difference between a Primary Chord and a Major Chord or are they the same thing?

In a scale pattern three tones seem to stand out as the strongest--the I, IV, and V. As the strongest tones they are the "primary" or most important, so to speak, and thus, chords built on those tones of a scale are 'primary chords' all of the others being secondary chords. Chords can be either major or minor depending on the arrangements of the whole and half steps. In C major for example the tones--C, F, G--are roots of the chords and they would be MAJOR chords. However, if C Minor is the scale the C, F, G again are the primary chords but the whole/half step arrangement is different and the C chord would be minor but still primary, the F chord would be minor but primary, and the G chord would be --um. . . .--major or minor depending on what form of the minor scale is in use. Usually it is the harmonic form so it would be major and a primary chord. ) I hope this isn't too confusing. With some thought you can see the difference. I, IV, V are primary in either case.

Is that the Humphries book? It covers a lot, but is like a quick summary, detail is sparse. If you want to learn chords, there are many other music theory books that spend many pages instead of one sentence. Or you can also find much online about these subjects by searching google.com, like for primary chord or major chord. Adding the word "theory" to that search will greatly help to filter results to acutal theory sites.

Primary chord pretty much means I, IV and V, primary in the sense of important or most commonly used. The I IV and V chords are both primary and major. A major chord means the chord third is not flatted (as opposed to a minor chord that is).

There are all manner of chords, but the I ii iii IV V vi vii nomenclature are a special class called normal chords, in that they are chords that only use the normal notes in the scale (for the notes within the chords), so therefore, it always comes out this way (for key of C):

I ii iii IV V vi vii
C Dm Em F G Am Bdim

I IV and V are major and primary.
The others are neither.

So those other chords like a Cm or D major chord are very possible to write and play, but they are not normal chords in the key of C.

Excellent Lightnin. Thank you. Now I understand more clearly the terminology.

Lightnin's dismissal of the other chords as 'neither' is not quite right. They are termed 'secondary' chords as gravitation to them is less likely than the stronger pull to I, IV, V. His Roman numeral classification is quite correct. Isn't it nice to get elucidation? He didn't discuss minor but the sequence is the same except the scale pattern is different. I, IV, V are the primary chords whether Major scale or Minor scale.

Sorry, I didnt mean to dismiss anything. I only intended to mean that the terms Primary or Major did not apply to any others except I IV V.

Yes, I did assume only Major keys, which should have been mentioned. Minor keys are ordered differently. I just meant that in the Major keys, the chords other than I IV V are always minor chords (and vii is diminished).

But it was Jean Phillipe Rameu in the 18th century that said I IV V were the most important, it wasnt me

The significance of this is: One can identify the key of a popular music song, and then write out the list of the I ii iii IV V vi vii chords to match that scale (the chord list is the scale note names, plus the maj/min/dim notations). Oserve the major/minor/dim chord notations very carefully (my nomenclature only applies to the Major keys). Then check the chord symbols used in that song against this list, and one immediately sees that this list is obviously the chords that are generally used in that key. This list is the "normal" chords for that major key.

But watch the major/minor notation carefully, they matter greatly. If Am is in the list, Am will probably be there, and very often if I IV or V, but an A chord probably wont be found in this key. The I IV V chords occur more frequently, the others somewhat less so. Other chords not in this list for this key are sometimes used, but more rarely, if at all.

It is really instructive to do this learning exercise, for many songs. Music generally uses these normal chords which match the key, and this list defines them. But music varies greatly of course. A Beatles song will be very much more normative (stays in the list, sounds normal), and jazz standards noticeably less so - a bit like bland vs interesting in that sense.

The above is very interesting and I am sure will become more understandable to me as I progress. However, I was hung up on some nomenclature which was clarified when "Primary" was explained for me. Now I am not sure, to quote Lightnin above "One can identify the key of a popular music song, and then write out the list..." what the term "key" means and how it can be identified.

I am not ambitious enough at this point to think of composing or arranging music, just to be able to read it and play it. I find it very difficult to read the music two staffs at a time, with the different notes, symbols, sharps and flats and then finger the right keys as well. I was thinking if I can learn by memory and practice the more common chords and their variations, I will be able to recognize them more quickly as I am playing and thus concentrate more on the fingering.

So, please explain "what the term "key" means and how it can be identified. I can tell you that without the help from this forum I would not be able to continue learning the piano as I cannot afford a regular teacher.

Thank you.

Lightnin is quite correct in that Rameau was a very important writer of music theory as well as a prominent composer of his time. You need time to digest this material but practise the chords. Technically there is only ONE major scale--that is the pattern of whole and half steps, i.e., w w 1/2 w w w 1/2, while there are THREE forms for the minor. Key refers to the starting point of the pattern which can be any tone. So if one starts on C then the pattern adapts to the white keys only (c d e f g a b c) and you have applied the pattern of whole and half steps. Were the pattern to be applied, say to D, then D would be the KEY (starting point) and the pattern would fall (d e F# g a b C# d) so KEY refers to the starting point of a scale pattern--major or minor. These two--major and minor--are the most frequently used patterns in western music. I hope this isn't too confusing! You need to 'meditate' on it for a while. Learn your chords and as you do it will become understandable. Good luck!

Daren, by key, I just meant the first note of the specific scale... The scale is the 8 note order, and the key is the first of those notes (the scale root) which defines the rest. More specifically the word key means the key signature at the beginnng of the staff lines which has the same key name... the key the song is written and played in. A key of C has a scale starting at C. This starting scale note defines the scale, and the key signature is shorthand to show which notes of the scale are to played as sharps or flats. The key is a generic name for the scale that starts on that note. I hope that is not double talk, dont make it be hard, its not.

For example, many songs are written in the key of C, with note I at C, so their key signatuare is blank, meaning no scale notes have sharps or flats (The C scale has all white keys). Some songs are written in the key of G with note I at G, which has a key signature of one sharp on F. Likewise a key of F with note I at F has one flat at Bb.

There are 15 of these possible keys, 7 sharps, 7 flats, and C with none. The Circle of Fifths shows these and their order, among other things. My piano teacher made me pass a written test to write out all 15 key signatures on paper in 40 seconds from memory. It is something we need to know to play songs other than in the key of C.

Below are the chords for the scales in the keys of C, G, F (beginning at C, G, F).

I ii iii IV V vi vii
C Dm Em F G Am Bdim (key of C major)
G Am Bm C D Em F#dim (key of G major)
F Gm Am Bb C Dm Edim (key of F major)

Step one at getting this is that a Major scale is defined by the scale note order W W H W W W H (Whole step, Half step), regardless where you start (scale root, or key). This is surely in your book, near the beginning. This is why some scales must use black keys, to maintain that W W H W W W H order for any major scale. Minor keys have different rules.

This order W W means the interval from 1 to 3 is always 4 half steps, by definition. A minor has only 3 half steps from 1 to 3, or said another way, the minor chord has a flatted third (lowered third compared to major chord).

So the reason we know ii Dm chord in key of C is minor, is because if in the key of C, we make a triad chord ii with root at D, and that chord uses only the notes of the scale (again, all white keys in key of C), then that 1,3,5 triad chord is necessarily DFG (using all white keys in this scale for C). However DFG is a minor chord, since the major would be DF#G (4 half steps). But F# is not in the scale of C, so DFG is a minor chord. ii and iii and vi and vii are alway minor in major keys (vii is diminished, 5 is also flatted).

The "Primary Chords" (I, IV, V) also covers every note in a major scale, and is sufficient to harmonize just about any melody in a major key. The practical implication is this: Take any melody in a major key and play it on a piano -- instead of testing a whole myriad of chords trying to find the ones that work, you can find chords that "work" with the melody much quicker by first testing the I, IV, and V chords. (Then as you become more experienced at "harmonizing-on-the-fly," the use of the other chords will come more naturally to you.)

Thank you all! I must pursue this in a new post.

One comment DarenT: it all may seem very interesting, but don't go that route yet. First learn what an interval is and how they help to give its name to a chord.
What you are asking in this thread belongs to basic harmony theory, and I don't think you should mess with that for now, or you'll find a whole mess of rules and complex analysis. Stick with learning the basics about scales, modes and intervals, since what you should focus for now is using those elements to help you sight read and understand a bit how music is represented on paper... at least in my opinion. If you get interested in theory a lot, and I think you are, you should also join a musical institution. Conservatories often have beginners courses for all ages.

Good advice. Thank you.

One last question for now. Does anybody know of a web site that has a comprehensive list of musical terms? There are so many terms it is easy to forget and get confused. For instance so far I have read of eight different types of Intervals throughout my course and yet when I look at some of the so called music dictionaries on the web they have a very limited definition. I tried book stores to see if I could buy a hard copy somewhere but to no avail. And one that specializes in Italian opera or symphonies would not be too meaningful.

Out of curiosity, what term? It would seem that either of
http://www.dolmetsch.com/musictheorydefs.htm
or
http://www.music.vt.edu/musicdictionary
should have almost anything.