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. The next type of 7 chord that I would like to discuss with you will be the dominant 7 chord. Now when it comes to 7 chords, we just don't have major minor like major, minor, diminished, augmented like we do with triads, we also have a new chord value or chord quality that we refer to as the dominant chord. Now the dominant chord is created by flatting the 7th notes, so the formula for that would be root, 3rd, 5th and flatted and 7. So basing that off my major scale here, my 2 octave major scale off the string is A. What I am going to have is a root, a 5th. Here's normally the 7th note of the major scale. We are going to flat it so 1,2,3,4,5,6,7 flatted. 1,2,3 we're going to add this 3rd here, 4,5, we add the 5th and the root at the top. So we have a root, 5th, flatted 7th, 3rd, 5th and root again. An A 7 or dominant 7. If you see the letter number of the chord with just the numbers 7 next to it. If there is nothing specifying whether the chord is major or minor, you assume that it is a dominant 7 chord. Major and minor must both be specified. Major with either m, a,g,a, capital or upper case M are often times a triangle symbol is used to specify major. Minor with a lower case m sometimes min or sometimes a dash symbol is used to specify minor but it is just the letter and the number 7 you have a dominant 7 chord. The same thing would apply to 9's, 11's and13's. You must specify major versus minor with those, otherwise you are playing a dominant chord.
