How to Construct a Major Key in Jazz Guitar

Video Transcript

" Hi! My name is John Armstrong with expertvillage.com. I'm a professional guitar instructor and today we are going to be studying beginning jazz guitar. Okay now that we've discussed our major minor diminished and augmented triads or chords, next it is important that you know how to put those together in a major key. We've talked about major scales and we've played the major scales. Next we need to understand how to put those triads together to create chords for a major scale to create a major key. Here we use the key of G major as an example but this same process will work with any major key. How we do this? How do we determine how to harmonize any diatonic scale, which is a 7 note scale, is to combine every other note in groups of 3 and figure out what type of triad or chord you come up with. So starting with the 1st, 3rd and 5th note of G major scale. I know I have a G, B and a D, so I know that my first chord in the key of G major is going to be a G major chord. Well that makes sense. Often the first chord in a key, whether it be major or minor referred to as the tonic chord of the key. So here my tonic chord is a G major chord, my one chord. My second chord, going to start on the 2nd note of the G major scale, an A note. If I combine every other note in groups of 3, I am going to see that I have A, C, and E. That gives me an A minor triad. Okay. So my 2nd chord, my 2 chord in the key of G major is A minor. So I have G major is my one chord or tonic chord, A minor is my 2 chord. My next 3 notes, every other note in groups of 3, are B,D and F sharp. Well, ha that's a B minor triad or a B minor chord. So my 3rd chord in the key of G major would be a B minor chord. So I've got G major as my tonic, A minor is my minor 2, B minor is my minor 3. My next 3 notes in groups of 3 are going to be C,E, and G. A C major triad so my 4th chord in the key of G would be a C major. So far I have G major, A minor, B minor, C major. My next 3 notes would combine in groups of 3 are D, F sharp and A, D major chord. My major 5. My next 3 notes are going to be E, G and B an E minor chord. My minor 6th chord. My next 3 notes are going to be F sharp, A and C, an F sharp diminished chord. My diminished 7 chord. So here are my 7 chords in the key of G major. G major, A minor, B minor, C major, D major, E minor, F sharp diminished resolving back to G major. This process of major, minor, minor, major, major, minor, minor, major diminished applies to any and all major keys using triads. "