4'33 (pronounced "Four minutes, thirty-three seconds") is a three movement composition that was composed by John Cage in 1952. It was composed for any instrument or combination of instruments, in fact the piece tells the performers to not play their instruments for the entire duration of the three movements. It is said to be a reflection of the influence of Zen Buddhism, something that Cage was studying throughout the years since the late 1940's. This idea first came up when Cage mentioned his desire to compose a piece entirely of silence. 

"to compose a piece of uninterrupted silence and sell it to Muzak Co. It will be three or four-and-a-half minutes long—those being the standard lengths of "canned" music and its title will be Silent Prayer. It will open with a single idea which I will attempt to make as seductive as the color and shape and fragrance of a flower. The ending will approach imperceptibility."

Chris Watson - Inside the Circle of Fire (2014)

"We tend to hear everything but we rarely listen"

Chris Watson is one of the world's leading Wildlife sound recordist, he was even in this business from the initial work he had for Tyne Tees television working on Attenborough documentaries. Having recorded everything from ants to elephants, he says capturing the sound of wild animals requires patience and the right equipment. The microphones are usually attached to very long cables - often a few hundred metres long - with Watson wearing headphones at the other end in a hide or a vehicle or hiding behind a bush so as not to disturb the wildlife.
  Most recently he has worked on a project called Inside the Circle of Fire which focuses on creating a sound map of Sheffield. Watson has been recording the sounds for the past 18 months and has captured what he believes shows the essence of Sheffield. It has all come together in the Millennium Gallery where all the sounds are playing on different speakers, and there's even some seats in the middle where you can go and collect your thoughts.

"When you go somewhere and really open your ears and really listen to a place - not just hear it, listen to it - that can be a really creative opportunity. Listening is a powerfully creative function and it can aid our daily lives."

Matthew Herbert - One Pig

Matthew Herbert is a British Electronic musician who uses everyday sounds and sounds from everyday objects, that he has recorded, to make his music.
"Over a 16-year career, Mr. Herbert has made provocative and sometimes bizarre music using noises he collects himself, often related to food and the body. He has woven rhythms out of rattling teeth and gulping digestive tracts; turned the cheep of a minute-old chicken into a funky bass line; and channeled the percussive crunch of 3,255 people biting into apples at once." [1]
Herbert followed the life of a pig from; death to birth; to being cooked, eaten and even digested; and recorded every sound possible along the way. This is how One Pig was born. He then managed to make each of these sounds into electronic music that became an entire album, and even manages to play them live to audiences.

“We live in a bubble, whereby we are separated from the consequences of our actions, whether it be the pollution that we make or the wars we start in distant territories or where our food comes from. It seems to me that one of the functions of art is to pop those kinds of bubbles.”