UNIT 1: QUALITIES OF SOUND. DURATION (RHYTHM) 1. SOUND, NOISE AND SILENCE Essentially, music is sound. SOUND is produced when an object vibrates and it is what can be perceived by a living organism through its sense of hearing. It travels through physical mediums by sound waves, and it is normally a pleasant feeling. Sound propagates at high speeds. The waves travel through the air at 340 meters per second. When sound waves find an obstacle on their way they are reflected or bounced back in the opposite direction of the sound source. (Echo) NOISE is a disagreeable auditory experience but this is a subjective definition. Anyway, the physical difference between sound and noise is the sort of waves: sound waves are regular and in a noise the wave is irregular. Finally, SILENCE is the lack of hearing sensation. Actually, there is not such a thing as absolute silence. Even if we could isolate ourselves completely from outer sounds, we would still hear our own body s inner sounds. John Cage, an American composer who explored the possibilities of sounds and silence in his compositions, was interested in silence. He wanted to experience absolute silence. He entered a soundproof chamber at Harvard University. It was supposed to be totally silent, but he heard two sounds. Later he discovered that these sounds were his heart beats. He discovered then that real silence is impossible while you are alive. John Cage's most famous musical composition is called 4'33". It consists of the pianist going to the piano, and not hitting any keys for four minutes and thirty-three. 2. QUALITIES OF SOUND Sound has four qualities or parameters which allow us to identify it: Pitch, duration, intensity and timbre. If we try to describe a sound with words, we have to point out: 1) If the sound is high or low, that is the pitch. 2) If the sound is long or short; we point out the duration. 3) If the sound is loud or soft, that is the intensity. 4) If the sound comes from a voice or an instrument we point out the timbre. PITCH Each note corresponds to a different pitch. These are the names we use to designate the pitch of sounds. DO RE MI FA SOL LA SI SPANISH C D E F G A B ENGLISH 1
To represent the pitch we use the staff, the clef and the notes. The staff is written as five horizontal parallel lines. The notes of the music are placed on one of these lines or in a space between lines. Extra ledger lines may be added to show a note that is too high or too low to be on the staff. The clef is the symbol at the beginning of the staff. It indicates the name that the notes are going to receive. The treble clef indicates that the note on the 2nd line is called G (sol). From that reference, we can deduce the names of the other notes on the staff. DURATION Note values are symbols that represent the different durations of sound. NAME Whole note Half note Quarter note Eighth note Sixteenth note SYMBOL w h Q e x INTENSITY These are indicators of fixed intensity and, therefore, they maintain the corresponding volume until another different indicator appears. The most common, from soft to loud, are: pp (pianissimo): very soft p (piano): soft mp (mezzopiano): moderately soft mf (mezzoforte): moderately loud f (forte): loud ff (fortissimo): very loud TIMBRE One of the basic elements of music is called colour, or timbre. Timbre describes all of the aspects of a musical sound that do not have anything to do with its pitch, loudness, or length. In other words, if a flute plays a note, and then a piano plays the same note, for the same length of time, at the same loudness, you can tell that the only difference is this: a flute sounds different from a piano. This difference is in the timbre of the sounds. Timbre is caused by the fact that each note from a musical instrument is a complex wave containing more than one frequency. For instruments that produce notes with a clear and specific pitch, the secondary frequencies that are involved in the sound are called harmonics. The human ear and brain are capable of hearing and appreciating very small variations in timbre. 2
Qualities of sound and waves Sound is produced by vibrating bodies, therefore, the different qualities of sound are due to the shapes and characteristics that those vibrations may have. The pitch of sound depends on the wave frequency: The vibration speed. It is measured in units called hertzes (Hz) which show the number of vibrations per second. The duration of sound depends on the wave persistence: How long the wave lasts until fading out. The intensity of sound depends on the wave amplitude: The distance between the highest vibration and repose of the object. It is measured in units called decibels (db). The timbre depends on the mixture of root and harmonic sounds, which are different in each voice or instrument. It s the colour of sound. When we hear a sound, it is never pure, it is a mixture of sounds with different frequency and vibration amplitude. QUALITIES DISTINCTION PRODUCED BY PITCH low high DURATION long short INTENSITY loud soft TIMBRE voices instruments 3. ELEMENTS OF MUSICAL NOTATION WHICH DETERMINE THE DURATION 1.1. Note values Note values are symbols that represent the different durations of sound. NAME Whole note Half note Quarter note Eighth note Sixteenth note SYMBOL w h Q e x 3
The Parts of a Note: It is usual to beam together the flags of eight notes and sixteenth notes that are part of the same beat, in order to make reading easier. A whole note lasts twice as long as a half note. A half note lasts half as long as a whole note A half note lasts twice as long as a quarter note. A quarter note lasts half as long as a half note. A quarter note lasts twice as long as an eighth note. An eighth note lasts half as long as a quarter note. An eighth note lasts twice as long as a sixteenth note. A sixteenth note lasts half as long as an eighth note. 1.2. Rests Rests are symbols we use to represent the duration of the absence of sound. They match with note values in name and length: NOTE VALUE NAME REST w Whole note h Half note Q Quarter note e Eighth note x Sixteenth note 1.3. Time signatures They are used to divide the time into equal parts and to set the length of note values and rests. They are represented by fractions: Numerator Denominator Number of beats Note value = 1 beat We can determine any time signature by joining the data: Beat note value (it fills one beat) x Number of beats = Measure note value (it fills one measure) 4
Types of time signatures according to the number of beats: Duple: divided into two beats Triple: divided into three beats Quadruple: divided into four beats Most common time signatures: 1.4. Note length modifiers Dot: it is a small dot placed on the right of notes and rests. It adds half of their value. Ligature: it is a curved line that links two or more notes that sound the same, adding up their lengths. Fermata: it is a semicircle with a dot in the middle. It extends the length of the note or rest, interrupting for a moment the time measure. 5
1.5. Tempo The tempo is the speed of the performance of a musical piece. Metronome: it is a device with a pendulum, similar to a watch, whose oscillations set the number of beats per minute. Largo: very slow Adagio: slow Andante: calm Allegro: fast Presto: very fast Vivace: very very fast 6