How Do Percussion Instruments Work?

Drums

Drums are the quintessential percussion instrument. They work through being struck on the head--the top of the drum, made from stretched natural or artificial leather or "skin"--and having this sound resonate through a cylindrical wooden frame.

Some drums play specific pitches. Timpani, or kettle drums, have their pitches adjusted by the tightening or loosening of the heads. Other drums, like rototoms, have a permanently assigned pitch.

Drums like snare drums or other set drums are played more for the quality of their sound than their specific pitch. They will sound higher or lower than one another, but they're not made to resonate with pitch easily identifiable on a chromatic scale. These drums are played for the quality of their sound, which may be dry and short (if the drum is small with a taut head) or boom-y and echo-y (if the drum is small with a looser head that vibrates longer and more slowly).

Keyboards

The word "keyboard" is often used to refer to piano-like instruments, but when it comes to percussion, this also means instruments like xylophones and marimbas.

These keyboards resemble piano keyboards but are played by being struck with mallets. The keys are made from bars of metal or wood that are arranged from large to small: the small keys play higher notes while the larger keys play lower notes.

Some keyboards, like bells, are made of a type of metal that has plenty of resonance and volume on its own when struck, so the instrument consists of just the metal keys on a frame. Xylophones, marimbas and vibraphones, however, need some added resonance, so each key has a resonating pipe below it which amplifies the sound with an echo. Like the keys, the pipes are arranged by size.

Auxiliary Percussion

After the two main schools are accounted for, there are still dozens of other supplemental--or "auxiliary"--percussion instruments we haven't talked about, and they all work in unique ways.

You might have metal cymbals (circular met discs which are suspended and make sounds when struck together or by mallets) or different types of shakers, which consist of different types of sealed, hollow containers partially filled with something like beads, which make noise by striking the insides of the container when shaken.

Other common auxiliary percussion can include bells, whistles, blocks covered in sand paper (they're rubbed together), hollow blocks of wood (they're struck), or really, anything that can be shaken or struck to produce an interesting sound. In fact, in addition to the traditional percussion instruments, many composers will specifically ask for particular pieces of "found percussion" made from household objects!