The dictionary defines a chord as; A combination of usually three or more musical tones sounded simultaneously.
On a guitar the most commonly used chords are probably power chords, a chord simply consisting of the root note and the fifth. They sound great with loads of gain, and most modern rock songs are build around them. I’m sure every beginner out there has has learnt some classics using power chords, and they form the basis of much of what any guitarist will do. Nirvana’s Smells Like Teen Spirit is one of the most memorable power chord sequences that I’m sure every teenager post-1991 has learnt at some stage in their guitar playing career, myself included.
What happens when you wish to go beyond power chords and start to add more voicing, depth and dynamics to your chord playing? In this article I will explain how you can add a few notes to the basic power chord to drastically change the sound, and the theory behind those extra notes and how they may be applied to other chords.
For this article I will assume you know how to play an A minor power chord. The chord is made from an A, played on the 5th fret of the low E string and an E played on the 7th fret of the A string. Most players usually add the octave to the root note and play the A on the 7th fret of the D string. A pretty basic rock power chord, and a basis for many songs over the years.
You can take this power chord and change the key and sound quite easily. At the moment the chord has quite a neutral sound, it could be major or minor as we haven’t added the third note yet that would make it into a ‘true’ chord. To make the minor you must simply add the minor third of the A minor scale, which is C. So a chord made of A, E and C is an A minor. You’re playing the root, the fifth and the third. If you raise the third one semitone to a D flat you’re playing the major third and so the chord will change from an A minor to an A major. Try playing the two different versions, you should hear the chord go from a sad sound to a happier sound.
These simple three note chords are known as major and minor triads.
This theory can be applied to all chords. If someone asks you to play a minor chord, you know that you must play the root note, the fifth note and the minor third. If you know your scales then this shouldn’t be too hard to work out. Don’t worry if it sounds too complex, after a while it’ll become second nature and you’ll begin to recognise and memorise the chord shapes. The advantage of learning chords on the guitar is that once you’ve learnt the shape then it can be moved up and down the neck to different root notes really easily.
For now that is the main basic theory behind major and minor chords. It is possible to add flavour to these chords by adding extra notes. I’ll run you through some of the ones I use the most and how you can play them as well. All these chords are based around that power chord start point of root, fifth and octave.
A common extension I use while playing guitar is the add9 chord. As the name suggest you’re adding the 9th note of the scale to the triad. You might ask how do you add the 9th note when there are only 8 notes in the scale? Well the 9th is really a relative term to your root note. Take the note nine intervals up from your root, which is an octave higher than the second. So in our A minor example you would play a B. Typically this note is played instead of the fifth, and is common in a lot of blues rhythm playing.
Another type of chord is a suspended chord. I use a lot of suspended second chords, written as Asus2. When playing a suspended second you remove the third and play a second instead. So an Asus2 consists of the notes A, E and B. These chords can give a lighter, dreamy sound and sound great through the clean channel with loads of chorus.
Seventh chords are also commonly used in many forms of music. Here you aren’t replacing any note from your triad, but you are adding another note to create a four note chord, called a tetrad. As the name suggests, you add the 7th note from the scale. In our example an A minor 7th would be played using A, E, C and G, where G is the 7th note of the A minor scale. It is worth noting that there are many different kinds of seventh chord, depending on the scale you’re using. To start with I would recommend getting comfortable using the natural minor and the major sevenths. A major seventh is played using a major triad and then adding the 7th from the major scale. To play an A major 7th you would play your A major triad consisting of A, E and Db before adding the major 7th, which is a B.
Hopefully that has given you more of an insight into how some basic chords are constructed and why they are named the way they are. Ultimately you want to make it your goal to be able to play any chord by just hearing the name and working out which notes you need to play. It can all seem a little technical and difficult at first, but trust me, it gets easier over time. Remember to take everything slowly and learn one thing at a time and get comfortable with it before moving on to something more complex. Good luck and I hope this article can be of some help to anyone struggling with their chords.
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Kaku’s latest book is The Future of the Mind: The Scientific Quest to Understand, Enhance, and Empower the Mind (http://goo.gl/kGrVaR).
The Universe in a Nutshell: The Physics of Everything
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What if we could find one single equation that explains every force in the universe? Dr. Michio Kaku explores how physicists may shrink the science of the Big Bang into an equation as small as Einstein’s “e=mc^2.” Thanks to advances in string theory, physics may allow us to escape the heat death of the universe, explore the multiverse, and unlock the secrets of existence. While firing up our imaginations about the future, Kaku also presents a succinct history of physics and makes a compelling case for why physics is the key to pretty much everything.
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