Let’s talk a little bit about acoustic guitar chords and in particular, dominant 7 chords which are one of the basic ‘must learn’ chord families every guitarist should know.
Chords are divided up into families which is a very natural way of grouping them together especially as every chord within that family will have the same ‘sound quality’ just at a different pitch or voicing. Major chords are a family of chords and are the starting point for many other forms of acoustic guitar chords especially as more notes get added or taken away from the major triad. There are many families of chords and after learning the major and minor families, dominant seven chords should be next on your list in terms of importance.
You may not realize it but dominant seven chords have been responsible for more innovation in music than any other. I’m not simply talking about acoustic guitar chords and modern music here but all the way back to Bach and Classical music, in every epoch of music there have been composers developing new ways of dealing with dominant seven chords which has in turn led to major developments in music. The importance of dominant chords and the influence they have had in music cannot be over stated.
The reason is because within all dominant seven chords exists an interval called a tritone, of all the 12 intervals we have available in music – the tritone is the most dissonant. It has an unsettling quality with a lot of energy and can also be labelled as a diminished 5th or augmented 4th depending on the musical circumstances. It’s the presence of this tritone within dominant chords that give them the desire to be resolved into another chord and this is what creates the tension and release you’ll often hear masterful composers manipulating. They can control the amount of energy and resolution in music through their ability to create and resolve tritone tensions.
Far from being important in just Classical music however, dominant seven chords are what Jazz music is almost entirely built around and furthermore what Blues music is based on too! You can see that their musical power is absolutely massive simply because of the opportunity they afford musicians to be creative and break new harmonic ground.
Acoustic guitar chords can be complicated or simple in the way they employ tritones. At the most elementary level we have simple dominant sevens such as C7, D7, E7, G7, A7 and B7. Those six would represent the most common dominant 7 chords for acoustic guitar and bands such as The Beatles are famous for using them in so many of their songs. They create strong cadences and when used with taste can totally lift a song to new heights.
In a major key the dominant 7 is placed upon the V chord so for example in C this would be…
C Dm Em F G7 Am Bdim
You can see that the dominant seven has been assigned to G as it is the fifth chord in the key and this creates a much stronger cadence from V to I in progressions due not only to the tritone being resolved but also due to the power of the cycle of fifths. If you can play G to C on your guitar then play G7 to C you’ll notice this difference. As with all acoustic guitar chords you must take care to ensure that every note is going to sound cleanly so that you’re able to hear the true voice leading as it unfolds within the progression.
In the minor key the addition of a 7 chord to the V is also very powerful and one only has to think of the sound of famous songs such as Hotel California or House Of The Rising Sun to realize the kind of tonality this creates. In the key of Am we would have…
Am Bdim C Dm E7 F G
The cadence of E7 to Am is again very powerful and distinctive. As we progress in our acoustic guitar lessons you’ll find that we are able to lift our guitar playing to an ever more refined and higher level through learning new acoustic guitar chord families. This will greatly increase your power as a guitarist and give you a lot more options for how to develop your acoustic guitar chord progressions.