Like any other art form or field of study we may wish to explore, music is made up of many parts and ideas. But, at its core there are only a few basic materials needed to create music. These basic building blocks of music are sound and time.
When you sing a catchy song or play your favorite instrument, you are producing sounds. In music, sounds are used to add structure to time. Time can be described as the duration of sounds and the silence between sounds. The relationship between sound and time can become quite complex, but in the end we find ourselves back at these two basic materials.
Sounds and Vibrations
Sound is a sensation that you experience when sound waves (vibrations) reach your ears. Merriam-Webster defines vibration as a periodic motion of the particles of an elastic body or medium in alternately opposite directions from the position of equilibrium when that equilibrium has been disturbed. That’s a little bit technical for musical applications. For our purposes, we will call vibration the periodic movement of a substance.
When you play an instrument, all the parts of that instrument, including the air inside and around your instrument vibrate. During vibration, the pressure in the air alternates between compressions and rarefactions. Compressions are increases in air pressure and rarefaction is a decrease in air pressure. A sound wave (vibration) is created by producing one complete cycle of compression and rarefaction.
The number of compression-rarefaction cycles that take place per second is known as frequency. The human ear can hear a range between 20 to 20,000 cycles per second.
Four Characteristics of Sound
Sound has four basic characteristics or properties, that we can identify. These properties are pitch, intensity, duration, and timbre.
Pitch is a term used to describe the highness or lowness of a sound. When we hear a difference of pitch we are actually hearing a variation in frequency. In other words, the more sound waves that are produced per second, the higher the pitch we hear. The fewer sound waves produced the lower the sound will be. A tone is a musical sound that has a defined pitch.
Intensity is used to describe the loudness or softness of a pitch. In music notation, we use a selection of Italian words and abbreviations to describe intensity.
Duration is the length of time a tone is sounded. To describe patterns of duration the terms meter and rhythm are used. Meter is a term used to describe regularly recurring pulses of equal duration. Usually, the pulses are grouped into patterns of two, three, four, or more. One of the pulses in each group will be accented. Together, these patterns of strong and weak pulses make up a beat. Rhythm works within the meter and describes a pattern of uneven durations. The steady beats of the meter combine to form measures, but rhythm may be a pattern of almost any length.
Timbre is a word used to describe the quality of tone or color of a sound.