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Pitch Here are some important points about pitch: • • • • Pitch is the “highness” or “lowness” of a sound and is scientifically measured as the frequency of a sound wave. We can compare two pitches and determine which sounds higher or lower than the other. We can hear an interesting phenomenon known as an octave as we travel upwards or downwards in pitch. When we listen to any two pitches that create an octave, we can simultaneously perceive how different they are (one is much higher than the other), and how much they are the same (they sound as though they are the same pitch). It is not just a coincidence that the higher pitch is exactly double the frequency of the lower pitch. While there are technically an infinite number of pitches, our system of music identifies only a small fixed number of pitches. Pythagoras (yes the triangle guy) experimented with vibrating lengths of string to arrive at the pitches we recognize today. Initially, Pythagoras identified seven pitches before we reach the octave and therefore use seven letters of the alphabet to name them. The space in between each of these seven pitches is not the same The name “C” repeats at the octave C D E F G A B C The space between “E” and “F” and “B” an “C” is half as big as all the others • • • • 1 A The smaller space is called a “half-step” while the larger space is known as a “whole-step” In order to have the same seven pitches in between every octave (from D to D, E to E, etc.) we will need more half-steps (e.g. between C and D, D and E…). The names for the “in-between” pitches use the words sharp and flat. A pitch that is a half-step higher than C can be called C-sharp (C#). A pitch that is a half-step lower that E can be called Eflat (Eb). When we want to be absolutely clear about a pitch, we use the word natural to describe pitches that are neither sharp nor flat. Ultimately, we end up with a total of 12 pitches identified using seven letters, sharps, and flats: 2 A# Bb 3 4 B C 5 C# Db 6 D 7 D# Eb 8 9 E F 10 F# Gb 11 12 G G# Notation Music existed long before notation, and we can make beautiful music without it. Still, the ability to read and write notation is an important skill for a musician and music theory student. Notation is presented on a grid called a staff. It is made up of 5 lines and four spaces, and allows us to represent the “ups and downs” of pitch visually. As we step up or down the lines and spaces of the staff, we step up or down the letters of the musical alphabet. In order to do this, we need a starting point. Much like the “You Are Here” arrow on the mall map, clefs indicate a reference point on the grid. A G-clef is used on the treble staff to indicate that the second line from the bottom is G the swirl circles the line An F-clef is used on the bass staff to indicate that the second line from the top is F the two dots are above and below the line Be careful of “shortcuts” that actually create confusion. “Every Good Boy Does Fine” and the many other tricks to remembering the lines can take us away from this simple fact: Pitches climb up and down the lines and spaces in alphabetical order. When we put the treble staff and bass staff together, we form a Grand Staff like the one below: EnharmonicPitch An enharmonic can be considered one pitch that has multiple names, or two pitches that have the same sound/identical frequency. This can be confusing, so let’s think about it for a minute: • • • The pitch between C and D is called C#. Could it not also be called Db? Is there such a pitch as E#? What about Cb? The answer to all of the above is YES! C# and Db are enharmonic. So are E# and F (natural). What is the enharmonic for Cb? Spelling Now all of this enharmonic stuff is not just a gimmick. There are important reasons to know which name should be applied to a given pitch. It does matter whether you call it C# or Db. Spelling counts! • • • One factor that determines the correct name is context. The key, the scale, or the chord in which a pitch is being used can determine which name is correct. Another factor is direction. When a pitch leads us upward by half-step, it typically uses its sharp name (e.g. C# leads us to D natural). In the opposite case, a pitch taking us downward by halfstep usually uses its flat name (e.g. Db leads us to C natural) Finally, I like to say that music is an “Equal Opportunity Employer.” As you will see when we build some scales, we use seven different letters to name the pitches. The ONLY letter name that repeats is the repeating octave. Scales A scale is a series of related pitches that have a distinct sound. A series because the ordering matters, and distinct because we can recognize it and distinguish it from others. Let’s take a look at how some common scales are constructed. As we saw in our discussion of pitch, two neighboring notes can be either a half-step or a whole-step apart. The series of notes C D E F G A B C makes up a major scale, and we saw that the spaces between E and F, and B and C are half-steps. In order to recreate the distinct sound of a major scale beginning and ending on any other note, we will need to introduce new pitches. This is because the location of the halfsteps (between the third and fourth notes, and between the seventh and eighth notes) is the identifying factor that we recognize as “major.” We must have half-steps in these locations to have a major scale. If we keep the same collection of notes (C D E F G A B C) but start in a different place (i.e mess up the order), we no longer have a major scale. For example, the series D E F G A B C D does not sound like a major scale because the half-steps between E and F, and B and C are now in the “wrong location.” In order to “fix” it, we will need to introduce new pitches. D E F G A B C D E>F needs to be a whole-step and F>G a half-step. This is easily fixed if we change the F into an F#. E to F# is a whole-step, and F# to G is a half-step. The same problem exists at B – C – D. Changing the C to a C# is the solution. The process of “fixing” scales to make them major occurs in a pattern known as the Circle of Fifths. CircleofFifths When we started talking about pitches, we first looked at the pattern from C to C. In the key of C, we don’t have to “fix” any pitches. We already have half-steps in the proper location without using any sharps or flats. This is why the key signature for C Major is no sharps or flats. C D E F G A B C Notice that the second half of the scale looks a lot like the first half. Each is made of two whole-steps and a half-step. This leads us to a great shortcut: G A B C is ready to go as the beginning of another major scale, no fixing necessary! In the second half of the G scale, I need to fix one note to follow the pattern D G A E F B G needs to become C D D E F# G E F# G This shortcut recurs on the fifth not of every scale. If I start with D E F# G (from above), the only note I need to fix is the seventh note, the one right below D. I need a C# Because of this pattern, musicians organize keys around a circle called the circle of fifths