Fundamentals of Acoustics and Music Theory
Contents – 1st & 2nd ESO
Item 1 – The Sound / Fundamentals of Acoustics
Physics is a science in which changes of state of bodies may be reversible, unlike chemistry, in which state changes are irreversible. (Think of the changes of state of water in physics vs. chemical combustion).
Acoustics is a branch of physics dedicated to the study of sound. Within this field, musical acoustics is a specific area of study.
Sound waves are transmitted, and we hear them, but they are invisible. The sound used in music is made with regular longitudinal waves. However, we need to differentiate between sound and noise.
Sound can have pitch or height, technically called frequency. Noise, on the other hand, cannot be tuned to a musical note. This is why music is (generally) made with sounds, not noise, although both can be perceived by the human ear.
Sound has 4 characteristics or qualities:
a) Hue (Pitch or Frequency)
A sound’s hue, also called pitch or frequency, determines how high or low it sounds. A higher frequency means a higher pitch, and a lower frequency means a lower pitch.
b) Timbre
Timbre is the quality that allows us to distinguish one sound from another, even if they have the same pitch. For example, a flute and a guitar playing the same note will sound different because they have different timbres due to their different constructions.
c) Duration
Duration refers to how long a sound lasts. It is measured in seconds (and later we will see how it’s represented by musical figures). Sounds can be long or short.
d) Intensity
Intensity is the force or power of a sound. We commonly call it “volume.” It is measured in decibels. In music, intensity is controlled through dynamics.
Item 2 – Graphical Representation of Sound
Musical Notes
In our musical system, there are 7 main notes: do, re, mi, fa, sol, la, and si (or C, D, E, F, G, A, and B in English notation).
Pentagram (Staff)
The pentagram, or staff, is where music is written. It consists of 5 lines and 4 spaces at equal distances from each other. The score is the staff plus the notes and other musical symbols.
Additional Lines (Ledger Lines)
Additional lines, or ledger lines, are placed above or below the staff to represent notes that are too high or too low to fit within the staff.
Clefs
The clef is a symbol placed at the beginning of the staff of a musical piece, indicating the pitch of the notes. The most commonly used clef is the treble clef (also known as the G clef), where the symbol indicates the G above middle C on the second line of the staff.
The treble clef is used for higher-pitched sounds, such as female voices, high male voices, and instruments like the guitar, flute, saxophone, and the right hand of the piano.
The bass clef (also known as the F clef) is used for lower-pitched sounds, such as low male voices, the left hand of the piano, and instruments like the bass, trombone, or tuba.
The C clef is less common today and is used for instruments like the viola or bassoon.
Alterations (Accidentals)
The smallest distance between two notes can be a tone or a semitone. A tone is equal to two semitones.
Alterations, or accidentals, change the natural pitch of a note by a semitone.
The three most common alterations are:
- Sharp (#): Raises the pitch of a note by one semitone.
- Flat (b): Lowers the pitch of a note by one semitone.
- Natural (): Cancels the effect of a sharp or flat, returning the note to its natural pitch.
Enharmonic Equivalents
Enharmonic equivalents are notes that sound the same but have different names. For example, on a piano keyboard, the black key between C and D can be called C# or Db.
This is a characteristic of our musical system where a single note can have two different names. For example, C# is enharmonically equivalent to Db, and E# is enharmonically equivalent to F.
Temperament and Scales
The Temperament System
Our current musical system, called equal temperament, was devised in the late fifteenth century by the Spanish theorist Bartolomé Ramos de Pareja. It divides the octave into 12 equal semitones.
An octave is the distance between two notes of the same name, such as from a low C to a high C. Within that distance, there are 12 semitones.
Chromatic Scale
The chromatic scale includes all 12 semitones of the equal temperament system.
C – C# – D – D# – E – F – F# – G – G# – A – A# – B (ascending)
Diatonic Scale
The diatonic scale consists of tones and semitones, with the semitones typically lying between the 3rd and 4th degrees and the 7th and 8th degrees (octave). The diatonic scale has 7 distinct notes, with the 8th note being the octave and the beginning of a new scale.
C (T) D (T) E (S) F (T) G (T) A (T) B (S) C (T = Tone, S = Semitone)
Item 3 – Rhythm
Rhythm, Meter, and Frequency
Rhythm is a natural phenomenon that exists both within and outside of music. For example, a day has a rhythm of 24 hours, and seasons change in a rhythmic cycle. This natural rhythm is based on frequency, which is the repetition of a sequence at evenly spaced intervals.
In music, meter organizes rhythm using a system based on the duration of notes and the division of time into measures (bars).
Note Values and Rests
Musical notes and rests are symbols that represent the duration of sounds and silences, respectively.
Each note value is typically half the duration of the next longer value (e.g., a half note is half the duration of a whole note). Conversely, each note value is twice the duration of the next shorter value (e.g., a quarter note is twice the duration of an eighth note).
Tie, Dot, and Fermata
A tie is a curved line that connects two notes of the same pitch, combining their durations.
A dot placed to the right of a note adds half of its value to the note’s duration.
A fermata (also called a hold or pause) is a symbol placed above a note, indicating that the note should be held for longer than its usual duration, at the performer’s discretion.
Time Signatures (Meter)
Time signatures are used to organize music into measures (bars). They consist of two numbers, one above the other, like a fraction.
The top number indicates the number of beats in each measure.
The bottom number indicates the note value that represents one beat (e.g., 4 = quarter note, 8 = eighth note).
Binary and Ternary Meters
A binary meter has two beats per measure.
A ternary meter has three beats per measure.
A meter can also be classified as having binary or ternary subdivision, depending on whether the beat is divided into two or three equal parts.
Item 4 – Melody and Harmony
Melody
A melody is a series of notes arranged in a musically meaningful way. It consists of phrases, which are short musical motifs that can be repeated and developed throughout a piece.
Harmony
Harmony refers to the simultaneous sounding of three or more notes, forming chords. It is the study of how chords are constructed and connected.
Chords
A chord is a combination of three or more notes played together. The most common chords are major and minor chords.
The main difference between a major and minor chord is that in a minor chord, the middle note (the third) is typically lowered by a semitone.
Major chords are often described as bright and happy, while minor chords are often described as sad or melancholic. However, these are subjective interpretations.
Item 5 – Organology and Timbre (Musical Instruments)
Timbre
Timbre is the quality of a sound that allows us to distinguish between different instruments or voices, even when they are playing the same note at the same pitch and volume.
Organology
Organology is the study and classification of musical instruments.
Instruments can be classified in various ways, but one common approach is based on how they produce sound.
String Instruments
String instruments produce sound through the vibration of strings.
- Bowed Strings: Played with a bow, such as the violin, viola, cello, and double bass.
- Plucked Strings: Played by plucking the strings with fingers or a pick, such as the guitar, lute, harp, and ukulele.
- Struck Strings: Played by striking the strings with hammers, such as the piano.
Wind Instruments
Wind instruments produce sound through the vibration of an air column inside the instrument.
- Woodwinds: Traditionally made of wood, though now often made of other materials, such as the clarinet, oboe, bassoon, flute, recorder, and saxophone.
- Brass: Made of metal, such as the trumpet, horn, trombone, and tuba.