The_Complete_Idiot%27s_Guide_To_Music_Theory

112
Part 3: Tunes
Note
The notes of a chord don’t
always have to be played
in unison. You can play
the notes one at a time,
starting (usually, but not
always) with the bottom
note. This is called arpeggiating
the chord, and the
result is an arpeggio.
Warning
You should always
spell a triad using every
other letter. So D♭-F-A♭ is a
correct spelling (for a D♭
Major chord), but the enharmonic
spelling of C♯-F-A♭
is wrong
Forming a Chord
Okay, here’s the formal definition: A chord is a combination of three or more
notes played together.
Let’s do a little exercise: Sit down at the nearest piano and put your right thumb
on one of the white keys. (It doesn’t matter which one.) Now skip a key and
put another finger on the third key. Skip another key and put a third finger on
the fifth key. You should now be pressing three keys, with an empty key between
each finger. Press down and listen to the music—you’re playing a chord!
Basic chords consist of just three notes, arranged in thirds, called a triad. The
most common triads are constructed from notes plucked from the underlying
scale, each note two steps above the previous note. So, for example, if you want
to base a chord on the tonic of a scale, you’d use the first, third, and fifth notes
of the scale. (Using the C Major scale, these notes would be C, E, and G.) If
you want to base a chord on the second degree of a scale, use the second,
fourth, and sixth notes of the scale. (Still using the C Major scale, these notes
would be D, F, and A.)
Building a three-note triad.
Within a specific chord, the first note is called the root—even if the chord isn’t
formed from the root of the scale. The other notes of the chord are named relative
to the first note, typically being the third and the fifth above the chord’s
root. (For example, if C is the chord’s root, E is called the third and G is called
the fifth.) This is sometimes notated 1-3-5.
Different Types of Chords
Let’s go back to the piano. Putting your fingers on every other white note, form
a chord starting on middle C. (Your fingers should be on the keys C, E, and G.)
Nice sounding chord, isn’t it? Now move your fingers one key to the right, so
that you’re starting on D. (Your fingers should now be on the keys D, F, and A.)
This chord sounds different—kind of sad, compared to the happier C chord.
You’ve just demonstrated the difference between major and minor chords. The
first chord you played was a major chord: C Major. The second chord was a
minor chord—D minor. As with major and minor scales, major and minor
chords sound different to the listener, because the intervals in the chords are
slightly different.