The Corvallis-OSU Symphony Orchestra is composed of students of all majors, OSU faculty, professional musicians, and members of the community. There are four families of instruments in the orchestra: strings, woodwinds, brass, and percussion.
The string section is usually the largest in the orchestra. The sound of a stringed instrument is made by the musician drawing a horsehair bow across the strings, which causes the strings to vibrate. Dynamics or the volume of sound increases and decreases by the speed and weight of the bow as it moves across the strings. Smoothness and sharpness are altered by gliding and stopping the bow. The strings can also be plucked. Pitch varies as fingers press the strings down as they progress up and down the fingerboard. Vibrato, the rapid small variation in pitch which adds warmth to music, can be seen as the small movements of the musician’s fingers on the strings. There are four instruments in the violin family of varying sizes, from the smallest – the violin, to the largest – the string bass. Other stringed instruments such as the harp, piano, and harpsichord can be considered both strings and percussion because of the struck manner of how they’re played.
The woodwind family of instruments were originally made of wood, though they can now be made of silver, gold, or other materials. Sounds are made by blowing air through a mouthpiece with a sharp edge, like a flute, or with a reed, which vibrates as air crosses it. Clarinets have a single reed while oboes and bassoons are double reeds. Sharpness and smoothness of sound comes from stopping the air flow or letting it flow. The pitch changes as fingers press down metal keys to cover holes in the instrument. Vibrato comes from the quick pulsing of air blown through the instrument.
Brass instruments make sound when the musician’s lips vibrate against a mouthpiece. Pitch changes using valves or slides on the long brass tubes of the instruments, which let air go through longer or shorter pathways before it exits the bell. In addition, musicians can change the pitch by varying the tension in their lips.
The percussion section has the most varied shapes of instruments. Sound is created by striking, shaking, or scraping the instrument. Some instruments, such as the tympani or xylophone, are tuned while others, such as bass drum, don’t have a definite pitch. Percussion adds rhythm, accents, and intensity to music, but can also contribute to melody and harmony.