Essentials of Music Theory: Elementary

by Carl E. Gardner

The key-tone is the tone from which a diatonic scale is built.

The numerical system is a movable system which means that 1 is always the key-tone. The theory name system is a movable system, the tonic being always the key-tone or 1. The alphabet system is a fixed system which means that a letter is always the same tone or its octave. The Italian system is treated as both a fixed system and a movable system. This book treats of the movable do, do always being the key-tone, 1 and tonic.

THE MAJOR SCALE.

A major scale is a progression from any tone to its octave in which chromatic steps are omitted between 1 and 2,—2 and 3,—4 and 5,—5 and 6,—6 and 7; from 3 to 4 and from 7 to 8 half steps are made.

Following is a diagram of a two octave keyboard:—

The keyboard shows white and black keys. The black keys are in groups of two and three. As can be seen in the diagram, the white key next to the left of the group of two black keys is c. The white keys in order to the right of c are respectively d, e, f, g, a and b. Following b is a repetition of c at the distance of an octave. Notice that between e and f there is no black key as is also the case between b and c. In these two cases, where no black key separates the white keys, the white keys are one semi-tone apart. Two white keys separated by a black key are one whole step apart. A black key is at the distance of a semi-tone from an adjoining white key. The black keys derive their letter names from the white keys. A black key is named from either of the white keys between which it is situated. The black key between c and d is named c sharp (#) or d flat (b).

Starting at c and sounding the white keys in order to the right as far as the octave produces the ascending major scale of C; sounding in order to the left produces the descending major scale of C. Notice that no black keys are necessary in the case of the C major scale, the whole and half steps being in their proper places; namely, whole steps between 1 and 2, 2 and 3, 4 and 5, 5 and 6, 6 and 7, and half steps between 3 and 4 and between 7 and 8. The student must constantly keep in mind the order of whole and half steps in all scales explained. In each scale explained the letters will be numbered and a curved line will connect those figures representing tones one half step apart.

All major keys except C major require one or more black keys. The number of sharps or flats required for a key is placed at the beginning of the staff and this is called the signature.