Aleatoric music is a type of music where some part of the composition is left to chance. John Cage is credited with being the first to create this type of music with his piece 'Music of Changes.'

Aleatoric music would probably be the best example.

The answer is Aleatoric :) This is an answer to a crossword clue and I have the following letters A-E-T-R-C Please help

It means by chance. In concert bands, they use it to do a scale in layers, meaning it is a random set of notes going up the scale. Look up the song," Alchemy, Spirit into Sound" and you will hear many measures of this concept.

Do something in an original & unusual way, something unexpected - in a sonic or formal way.

either: [1] making sounds on an instrument in an unusual way (bowing a cymbal while immersing it in water), or making sounds on an "unusual instrument" (an Ebow on a toaster or playing cutlery) or [2] constructing music in an unusual way (John Cage & the I-Ching) or writing something that will have to be interpreted in an unusual way (graphic notation or some extension, thereof).