Now for Perfect Intervals. Like I said before a perfect interval is called so because of its perfect mirror like image when it flips. So the intervals that are perfect are unisons, 4ths, 5ths, and octaves. If you flip a unison it is still a unison, if you flip an octave it is still an octave, then if you flip a 5th it’s a 4th, and if you flip a 4th, it’s a fifth. The fifth is also called the dominant for its strong presence I also think it is perfect due to its importance in chords!
So first let us go over what exactly a unison is. A unison is from one note to the same exact note. Not an octave higher or lower and also not the same tone. But actually note so C-B# is enharmonically the same but is not a unison.
So here are all Perfect Unisons:
It is the first scale degree of the major scales!
The next perfect interval is a Perfect 4th. A lot of music theorists have argued that a 4th is not perfect due to its consonance but it still is considered perfect due to its great connection to the 5th, the circle of 5ths and its main purpose in chords.
Here are all Perfect 4ths:
These are all the 4th scale degree in the major scales. They are also 2 whole steps and one half step away.
The third perfect interval is the Perfect 5th. The perfect fifth is also known as the dominant, which we will talk more about later. But just the word dominant means “very important, powerful, or successful” – Merriam Webster Online Dictionary. So why wouldn’t a 5th be perfect!
Here are all Perfect 5ths:
These are all the 5th scale degree in the major scales. They are also 3 whole steps and one half step away. The circle of fifths also show these just in a different order than I did.
The last perfect interval is the Perfect Octave which is the same exact note an octave higher or lower. Fun fact, music and sounds aren’t actually higher or lower, they are slower or faster. The slower the frequency the lower pitch it makes and the faster the higher it makes!
Here are all the perfect Octaves:
So these are all the perfect intervals that we will be studying.
Now to recap a minor interval is when you lower a major interval by a half step.
A diminished interval is when you lower a perfect or minor interval by a half step.
And an augmented interval is when you raise a perfect or major interval by a half step.
Here are 4 pictures showing the Perfect unison, perfect 4th, perfect 5th and perfect octave.
The 1st picture showing all perfect unisons on treble and bass clef played one after another in each measure using half notes.
The 2nd picture showing all perfect 4ths on treble and bass clef played one after another in each measure using half notes.
The 3rd picture showing all perfect 5ths on treble and bass clef played one after another in each measure using half notes.
The 4th picture showing all perfect octaves on treble and bass clef played one after another in each measure using half notes.
HOMEWORK: Give me 2 examples of each type of perfect interval! Either type it out or use finale to write them out!
The next task will talk about minor intervals!