If you have read Music theory for Guitar you may already be able to play Do Re Mi in one or more keys on the guitar. At least you know what we mean by a Key. It’s just the diatonic scale starting with some specific root note. We know that we have 12 possible keys A thru G# but most guitar players prefer C and G or A and D.
Keys in common use are “white” keys and C is the most popular of them all. In fact for a guitar player the key of A is a better choice to start because the shapes are easier and you can use open strings for a bass line. D is also a good Key for the same reason and it is a forth above A so I suggest you learn the grips for D and A to start. I’ll continue with the theory of these simple chords since you can find the shapes here and the video will show you how this works in practice.
Major Chords — the major triad
If we take any diatonic scale and express it as one thru seven ( 1 – 7 ) we have a simple scheme for building chords and talking to other musicians. The rule for creating a major triad is play every other note. That is the root chord for any scale is 1 – 3 – 5. We usually say this as first, third and fifth of the scale. Now since we have memorized the diatonic scale as a fingering, a pattern that never varies we can play the a chord root of any scale as a bass line or a lead line so that all keys are alike to us. The finger pattern to the diatonic scale should be in your hands in muscle memory. One this happens you are on your way to being able to play what you hear and you have a selection of notes that will sound good over any chord.
Chord Scale – Nashville Notation
You might wonder what happens if we take the 1 – 3- 5 which forms the root chord and add one to each note. On a keyboard this corresponds to taking the C chord and moving it one key to the right. As every piano student knows this gives you D minor. And if we take the 2 – 4 – 5 notes from the C scale on the guitar we also get D minor, but as before the 2 – 4 – 5 from our fingering of the diatonic scale gives us the 2 minor of whatever scale we started with. Note please, that these arpeggios will not be suitable for playing as chords because two notes are often on the same string.
For those who already have some knowledge of chord shapes let me say that in C the chord scale consists of the following chords each triad being derived by adding one to each note of the previous triad. C, Dm, Em, F, G, Am, Bdim.
Try it, you will play Do Re Mi in chords. These are called 1 thru 7 in Nashville notation where it is understood that 1, 4, and 5 are Major and the rest are minor except 7 which is dim. Jazz musicians usually express the chord scale as I, ii, iii, IV, V, vi, 7. Either notation provides of means of transposing any key into any other key. When you can use bar shapes to do this you are no longer a beginner. Ease of transposing is what makes bar shapes important.
When most folk/rock/country guitar players think of a key they think of a set of chords that fit together to accompany a song and not necessarily of the major scale that provides the individual notes. As it happens the most common group of chords in use is called a 1 – 4 – 5 and these are just chords built on the first, fourth and fifth notes of the key that the singer chooses to sing in. They are also the major chords of the key.
Using the Capo
Guitar players seldom get to pick a key. If a singer wants D# also known as Eb you just suck it up and either play single notes in the scale or find a capo and move your favorite chord shapes up the neck until they sound in Eb. C for example sounds D with a capo at the 2nd fret and Eb /D# with the capo at 3. A beginner who can play only A and D would play D with the capo on the first fret. Once you learn two keys a fourth apart you can use a capo to play anything that is in a major key. C, G, and a capo give you every possible key but G requires Bm which is a bar as difficult as F.
Minor keys/chords are a challenge for beginners because some bar chords are required. C is the easiest key to play a complete chord scale but it does have the dreaded F chord which has at a minimum a small bar. If you can play a full F bar and a full B minor bar you are no longer a beginner and are well on the way to 7th chords and blues.
Another good reason to learn to play the diatonic scale is that it gives you all the pentatonic scales which are much used in blues and Jazz music. The pentatonic scale is just 1 – 2 – 3 – 5 – 7 of the diatonic scale. By eliminating the fourth and sixth of the major scale we get a set of notes that almost always sounds consonant so many teachers skip the theory above and just tell students to memorize pentatonic scales. One problem with this for ear players is that these scales are difficult to sing so if you wish to go that way you have to practice.
Jazz musicians say that with a capo on your dash board you are allowed to park your car in handicapped stalls but if you can use a capo you are on the way to making up your own arrangements.