Welcome on my Chords Webpage.
A basic chords knowledge.
We will try here to understand how
chords are constructed. We have seen in the Intervals section the name
of those distances. Now, we have those intervals played simultaneously.
Pick two or more strings at the same time and you will play a chord. The purpose here is not to try to know the name of all chords by heart but rather to understand how to construct them.
Under the C scale below one has "Place of note in chords". This is practical when writing or reading chords, since it helps to situate whether it is a C11, C9, C7, C13, and so on. Also, another notion to take into account is chord degrees. See again picture below under "Chords degrees" (for both triads and seventh chords) a number showing where a chord stands. (I- first, II- second, VI- sixth position) and so on. This is crucial when it comes to analyzing chord functions.
Now, let's start off with C major chord. C will be the root of the chord, namely the Tonic. Then we will use three notes above the tonic: 1- a Tonic (1), 2- a Third (3), 3- a Fifth (5), 4- a Seventh (7). Then, I would advice to examine thoroughly the table below "Type of chords" and try to compose your own chord taking examples in the row "Melodic intervals". The chord, C-M7, is part of row 3. Next, CM7(b5) is part of row 13 and lastly C7, row 11.
Below is a four notes harmonization of a C major and minor harmonic scale.
See Chord G7, in the major and in the harmonic minor, in both case, it is a Major7 chord Called Dominant seventh, (written V7).
Conclusion: all dominant seventh chords are Major with a minor seventh, regardless of the key.
Now one knows, that, a Dominant seventh chord has a diatonic function.
Since it is always placed on the V7 degree, a dominant seventh determines a key signature. (a D7 chord is in the key of G)
E7 chord, shows that we are in the key of A, similarly, with D7 we are in G and so...
A good reason to learn the Circle of Fifths.