Intervals And Accidentals
Run time: 4m 42s | Release Date: June 18th, 2012
An interval is the distance from one note to another note either above or below the original note.
The two most basic and important intervals to know about are a half step and a whole step. Let's start with a half step.
A half step is the distance from one note to the very next note either directly above or below the original pitch. This is probably most easily understood by looking at the keyboard of a piano. If I was to, for instance, start on the note B and go up one half step I would end up on the note C. The very next note above the note B is C. Likewise, if I was to start on the note C and go down one half step I would end up on the note B. The very next note below the note C is B.
Let's try it again, this time starting on the note E. Starting on E and going up one half step would take you to the note F. The very next note directly above the note E if F. And just like earlier, if our original note was F and we went down one half step we would end up on the note E. The very next note directly below the note F is E.
This is very important to remember: B and C, and E and F, are the only two sets of natural notes which are separated by half steps. All other natural notes are separated by whole steps.
Now that we know what a half step is, a whole step would be much easier to understand. A whole step is simply the distance of two consecutive half steps. Let's start on the note A. If we go up one half step from the note A it will take us to this black key. We know that a whole step is two consecutive half steps, so if we go another half step from this black key we will end up on this note, B. Let's review that quick: if we start on A and go up one whole step we end up on the note B.
Let's try it one more time, this time we will start on the note D. Just like before, if we start on the note D and go up two half steps we end up on the note E; two half steps equals one whole step.
Now, the black keys on a piano do actually have letter names. This is where the term accidentals comes in. An accidental is a symbol placed next to a note that raises or lowers that note by step.
The first commonly used accidental, a sharp, raises a note by one half step. This means that because this black key is one half step above the note F, then this black key is actually the note F#. One half step above the note F is F#.
The second accidental, flat, does the opposite of a sharp. A flat lowers a note by one half step. If we take a look at the note E and see that this black key is one half step below E, then this black key is actually the note Eb (E flat). One half step below E is Eb.
Now, you may be thinking that this black, Eb, is also a half step above the note D, and you are right. Each of the black keys can technically be called two different letter names, one sharp and one flat.
Before we wrap up, let's take a look at a few whole steps and half steps which incorporate accidentals. If I start on the note G#, and I go up one half step, I will end up on the note A. One half step above G# is A. Likewise, if I was to start on the note C# and go up one whole step I would up on the note D#. One whole step above the note C# is D#.