The tradition of dividing instruments into families is known as Organology. Some of the first western texts we have on this subject date to the 16th century, and even though there’s been much deliberation on this topic there are some generally accepted groupings:
- Strings family – These are instruments where the sound is produced from vibrating strings that are manipulated by the touch of the performer.
- Brass family – These instruments produce sound by sympathetic vibration of air via the performer’s lips in a tubular resonator.
- Woodwind family – These instruments fall into two categories: reed instruments and flutes. The sound is created by dividing a column of air with a reed or a fipple (the mouth piece of a flute/recorder).
- Percussion family – These instruments also fall into two main categories: pitched and un-pitched. The sound is created by striking the instrument with some kind of mallet or stick.
- Keyboard family – These instruments include pianos, synthesizers, and organs. The technique is relatively the same from one keyboard instrument to the other, but the way in which the sound is produced can vary greatly from one instrument to the other. The piano strikes strings with hammers (almost like a percussion-string hybrid) while the pipe organ pushes air through pipes (similar to woodwinds).
Understanding instrument family timbres
It’s important to remember that there’s a wide amount of timbral variety inside of each of these family groups, however, some generalities can be observed:
- The brass and percussion families are capable of some of the loudest dynamics in the acoustic instrument world
- The classical strings (violin, viola, cello, double bass) share surprisingly uniform timbral characteristics. These similarities allow for the lush combinations of sounds that orchestras are known for.
- The woodwind family contains a very diverse set of timbres ranging from the flute (possibly the simplest of tones) to the double reeds (very distinct nasally tones). They can produce a wide variety of dynamics and can blend well with all of the other families.
- The keyboard family is unique in that a pianist can essentially play any keyboard instrument with a small learning curve. The keyboard family also has a very diverse range of sounds (especially when electronic synths are considered). Typically, pianos are the most common keyboard in acoustic composition.
- The percussion family is widely used for emphasis in the orchestral and band settings, but are fully capable of expressing nearly any emotion in music.