Topic 3: Frequency and Notes

 



Frequency is the number of cycles of a wave that occur in one second, measured in Hertz (Hz).
It is an essential concept in understanding the relationship between music and sound waves.
The frequency of a sound wave determines the pitch of the sound that is produced.

In music, the basic building blocks of sound are the musical notes.
Every note has a specific frequencies and hence a specific pitch. 

The specific frequency of a note  can be calculated using the formula:

f = f 0  2 n / 12


f0 is the frequency of the A note. (440hz)
n is the number of semitones between A and the note in question.

NoteFrequencyFormula
C4261.63 Hzf = 440 * 2^(0/12)
C#4/Db4277.18 Hzf = 440 * 2^(1/12)
D4293.66 Hzf = 440 * 2^(2/12)
D#4/Eb4311.13 Hzf = 440 * 2^(3/12)
E4329.63 Hzf = 440 * 2^(4/12)
F4349.23 Hzf = 440 * 2^(5/12)
F#4/Gb4369.99 Hzf = 440 * 2^(6/12)
G4392.00 Hzf = 440 * 2^(7/12)
G#4/Ab4415.30 Hzf = 440 * 2^(8/12)
A4440.00 Hzf = 440 * 2^(9/12)
A#4/Bb4466.16 Hzf = 440 * 2^(10/12)
B4493.88 Hzf = 440 * 2^(11/12)




Relationship Between Musical Notes, Intervals, Whole Tones, and Semitones

The distance between any two notes on the musical scale is known as an interval. Intervals are fundamental to music because they determine the melodic and harmonic progressions that create the distinctive sounds and emotions of different musical styles.


Types of Intervals

Intervals are categorized based on their size.
The smallest interval is a semitone, which corresponds to a frequency ratio of approximately 1.059463. A whole tone, on the other hand, is two semitones, or a frequency ratio of approximately 1.122462.

Whole tones are considered the basic building blocks of melodic motion, while semitones provide the necessary inflections and nuances that add expressiveness to melodies.

Semitones or half tone, simbol used: S or H

Whole tone or tone: T or W


Interval Ratios

The exact proportions of whole tones and semitones are determined by the mathematical relationship between the frequencies of the notes involved. For instance, the interval between A and B, a whole tone, can be expressed as a ratio of 9:8, where 9 represents the frequency of A and 8 represents the frequency of B. This ratio ensures that the two notes produce harmonious vibrations when played together.


Music Theory and the Relationship of Notes to Intervals

The study of musical notes and their relationship to intervals forms the cornerstone of music theory. It provides musicians and composers with a framework for understanding the structure and organization of music, enabling them to create melodies, harmonies, and rhythms that are both pleasing to the ear and structurally sound.


The Impact of Intervals on Musical Expression

The choice of intervals plays a crucial role in shaping the emotional and expressive qualities of music. For example, minor thirds, which have a frequency ratio of approximately 6:5, tend to evoke a sense of sadness or melancholy, while perfect fifths, with a frequency ratio of approximately 2:1, are associated with feelings of stability and harmony.


Appreciating the Beauty of Music Through the Language of Notes and Intervals

Understanding the relationship between musical notes, intervals, whole tones, and semitones grants us a deeper appreciation for the beauty and complexity of music. It allows us to recognize the subtle nuances that give each piece its unique character and emotional resonance. As musicians, composers, or simply music lovers, we can unlock a whole new dimension of enjoyment by delving into the mathematical and sonic underpinnings of this universal language of expression.