|The Foundation and Basics of Music Theory|
The term interval refers to the distance from one note, to the other.
When first learning, it is very important that you know why the notes
"E" and "B" in a scale are different then the others. For example, if you
have an "E" - Sharp, its sounding pitch is "F", therefore another half step
up (or the next key up on the piano) would be "F" - sharp. if you
have a "B" - Sharp, its sounding pitch is "C", therefore another half step
up (or the next key up on the piano) would be "C" - sharp. If you do not
understand this, then do not go on untill you do. (Scroll down to
Enharmonic Intervals for an example)
The very first thing you should learn about intervals is whats called enharmonics. Enharmonics are the exact same pitch, just spelt differently. For example, "C"-sharp is the same key on the piano as "D"-flat. Why are they spelled differently if they sound the same? The answer will eventually become obvious as you learn. Keeping in mind the differences with "E" and "B" from the previous paragraph, "E"-sharp is the enharmonic of "F". The note "C"-Flat is the enharmonic of "B".
The first step to figuring an interval is to count how many notes away from eachother they are. For instance, if you have the notes "C" to "G", you know that the interval is a fifth. "C"-1 "D"-2 "E"-3 "F"-4 "G"-5. (If it is the same exact note on the same line or space, it is called a perfect unison.)
The next step is to figure out what quality the interval is. There are five types of qualitys: Major, minor, augmented, diminished, and perfect. The chart below refers to figures 1-12 to show how many half steps there are in the major, minor,and perfect intervals.
|Intervals and Their Qualities|
|Interval||Number of Hlaf Steps||Figure #|
|Diminished, Augmented, and the Tritone|
If a perfect or major interval is made one half step larger (without changing
its interval number) it becomes augmented. If a perfect or minor
interval is made one half step smaller (without changing its interval number) it
becomes diminished. An augmented fourth (and it's enharmonic - a
diminished 5th) is called a Tritone.
Enharmonic Intervals are intervals with the same sound that
are spelled differently.
If you were to play the above example on a piano, you would find that you would be playing the exact same notes each measure. They all sound the same, but are spelled differently. The reason for spelling them differently becomes obvious when you learn more about theory. Care must be taken in spelling intervals. If a specific interval is requested, the enharmonic-equivalent spelling is not correct. Thus, if a major third above E-flat is called for, a diminished fourth above D-Sharp is not correct, even though the sound is the same.
The inversion of an interval means that the lower tone of an
interval becomes the higher tone, or the higher tone becomes the lower tone.
|Interval Name||When Inverted Becomes|
|Some Typical Intervals & Their Inversions|
Intervals greater than an octave are called compound intervals. These intervals are
named in a similar manner to the intervals within an octave (simple intervals).|
The compound intervals are often labeled as their simple evuivalents-as if an octave were removed from the interval. The compound names are used only if it is important to stress the exact interval size.