Percussion Energy

Percussion instruments are some of the most amazing instruments in the orchestra. All kinds of shapes and sizes make up the percussion section. And all kinds of sound energy comes from the instruments. They rattle, bang, crash, swoosh, thump, whisper, tinkle, and more.

Percussion describes instruments that are struck or strike themselves to get the sound energy from them. But really some of the instruments in this section don't work that way at all. There are two basic groups of percussion instruments. One is the membraphones and the other is the idiophones. In these two groups you have two other divisions; the instruments that have definite pitch and those that don't.

Membraphones are basically the drums. A membraphone is an instrument that has a membrane, or skin covering one or both ends. The timpani has a membrane on the top and the snare drum has membranes on both sides but they both work the same way. The energy that they use is also acoustic energy like other instruments. Just like when the strings of string instruments are tightened their pitch goes up; that is what happens to membraphones.

Some membraphones have a definite pitch but most don't. Like the other instruments we have talked about the bigger the drum the louder and deeper the sound you get from it. A percussionist stikes his instrument to produce a sound. This causes a vibration of the skin of the instrument and the air inside the drum will vibrate also. This makes the sound even larger. The instrument is hit with a mallet, a hammer, or a hand and this causes a vibration and sound. This image shows how a drum head vibrates.

The second kind of percussion instruments are the idiophones. These instruments are ones that make their own sound. The instrument itself vibrates and makes the sound. Some idiophones would be the cymbals, gongs, xylophones, and tubular bells. Most bells have definite pitch but gongs and cymbals don't.

Making Sound Energy with Percussion Instruments