Music Theory (Basic Level) - Part 2 : Intervals continued ..

This article was originally written by Eowyn. It is going to be published part by part in DTB, to help the guitarists over the world to learn music theory in details.

When the notes are played sequentially, the interval is called "melodic".When they are played simultaneously, it is called"harmonic".

The name of an interval depends on the number of notes it contains, including the end notes; for example, the interval C - F contains 4 notes (C, D, E, F), and will be called a “fourth”. The type of an interval depends on the number of H's and W's that it contains. An interval can be "minor" (m), "major" (M) or “perfect” (P); in addition, intervals can be “augmented” (aug or # or +) (raised by an H) or “diminished” (dim or b) (lowered by an H). When nothing is specified, the interval is considered to be major or perfect.


Here's a table of the intervals you should know:

The “8” is not called a perfect eighth but a perfect octave or simply octave. Intervals can span more than one octave. A "9th" is a 2nd an octave higher, an "11th" in a 4th an octave higher and "13th" is a 5th an octave higher. I've never seen intervals larger than a 13th being used in practice... and in blues and rock music, you'll rarely need more than the m7.

And finally this: make sure you know the difference between a "chromatic" H and a "diatonic" H:

• A chromatic H is when you raise (or lower) a note by an H without changing its name. For example, C - C#, Db - D, Gb - G, A - A# are all chromatic intervals.
• A diatonic H is when you raise (or lower) a note by an H and change its name. For example, C - Db, C# - D, F# - G, A - Bb are all diatonic intervals.

Please note: C - C# is musically identical to C - Db... but not theoretically. Damn theorists!

To be continued...

Music Theory (Level : Basic) - Part 1 : Intervals

This article was originally written by Eowyn. It is going to be published part by part in DTB, to help the guitarists over the world to learn music theory in details.

Theory
Intervals aren’t much fun to learn but they are essential and we'll need them:
• in the context of scales
• in order to define chords
• to help in analysing phrases and solos
and most importantly, we absolutely need to know how to play them. So please, bear with me and
read on.
As you probably know, the whole western musical system is built on 12 notes:

Some points worth noting:
• Some notes have two names (e.g. C# - "C sharp", or Db - "D flat"). This is required
for theoretical reasons that we will not go into but in practice they are one and the
same note.
 
• This ordered sequence of notes is called a scale; this particular one is the
"chromatic scale". We'll get into scales in future topics.
 
• Between any pair of consecutive notes in the scale above, there is an equal
distance of a halftone (H); two halftones form a whole tone (W). Because of that
equal distance of a halftone, this scale is called equal-tempered. Why there are
only twelve notes and why there is that equal distance of a halftone between any
pair of adjacent notes is a very complex subject that we won’t go into here.
 
The "distance" between two arbitrary notes is called an "interval".


To be continued...