Percussion instruments naturally create ambient noise in music; often, non-pitched instruments are used to create unusual effects. Using common instruments to create new sounds is common in orchestral music. Small cylindrical disks called crotales create an ethereal sound when bowed with a violin bow instead of striking them with a mallet. Rain-sticks mimic the sound of rain and wind machines create a whirling wind effect. There are also thunder sheets and rolling bass drums that create thunderous and low, booming sounds.
Stringed instruments are capable of sustaining sounds for long periods of time; trained performers can create an imperceptible change between bow strokes to play ambient drones and high tessituras without break. These techniques can create a suspenseful mood in the music. Players can also use a hard pizzicato technique called a "snap pizzicato" or a "Bartok pizzicato" to create a loud snapping sound as the string makes noise when it strikes the fingerboard. Another technique, called "col legno," asks players to use the wooden back of the bow to play the strings; with this technique, a dry crackling sound can evoke images like dancing skeletons and breaking wood.
Electronic media is sometimes included with modern orchestral pieces; welectronic sounds, it is possible to stretch, skew and isolate particular moments of sound and extend and distort them to create new effects. A composition by Kevin Ure called "The Key" uses a set of keys to create several ambient effects to form a complete composition. Composers with expertise in electronic music and manipulation can create magnificent new sounds.
Brass and woodwind instruments are capable of several techniques that create interesting background effects. Key clicks are a technique used in some 20th century music; this technique asks the player to quickly move the keys or valves of the instrument while blowing to make noise, but not creating a traditional pitch with the instrument. Instruments may be taken apart in unusual ways to create high shrieking screams and wind effects. Glissandi and other sliding tones create non-specific tonal events that create discord and suspense within the music.