Luigi Russolo in the context of "Sound art"

Noise music (or simply noise) is a subgenre of experimental music that is characterised by its use of unwanted noise as a primary musical element. The genre has roots in early 20th century avant-garde music, but later drew influence from industrial music. It is characterized by a rejection of conventional music theory and traditional song structures, often featuring little or no melody, rhythm, or harmony. This type of music tends to challenge the conventional distinction between musical and non-musical sound.

"Noise as music" originated as an avant-garde music style in the 1910s through the work of Luigi Russolo an Italian Futurist, who published the manifesto The Art of Noises in 1913. Elements of noise music were later explored by artists in the Dada and Fluxus movements, as well as through electroacoustic music, modern classical and musique concrète. Composers such as John Cage, Edgard Varèse and James Tenney would explicitly use the term "noise" to describe some of their experimental practices. During the 1960s and 1970s, compositions such as Robert Ashley's "The Wolfman" (1964) and Pauline Oliveros "A Little Noise In The System" (1967) were among the earliest examples of contemporary noise music. While works by non-academic artists such as Lou Reed's Metal Machine Music were influential for later noise artists.

Futurism (Italian: Futurismo [futuˈrizmo]) was an artistic and social movement that originated in Italy, and to a lesser extent in other countries, in the early 20th century. It emphasized dynamism, speed, technology, youth, violence, and objects such as the car, the airplane, and the industrial city. Its key figures included Italian artists Filippo Tommaso Marinetti, Umberto Boccioni, Carlo Carrà, Fortunato Depero, Gino Severini, Giacomo Balla, and Luigi Russolo. Italian Futurism glorified modernity and, according to its doctrine, "aimed to liberate Italy from the weight of its past." Important Futurist works included Marinetti's 1909 Manifesto of Futurism, Boccioni's 1913 sculpture Unique Forms of Continuity in Space, Balla's 1913–1914 painting Abstract Speed + Sound, and Russolo's The Art of Noises (1913).

Although Futurism was largely an Italian phenomenon, parallel movements emerged in Russia, where some Russian Futurists would later go on to found groups of their own; other countries either had a few Futurists or had movements inspired by Futurism. The Futurists practiced in every medium of art, including painting, sculpture, ceramics, graphic design, industrial design, interior design, urban design, theatre, film, fashion, textiles, literature, music, architecture, and cooking.

The Art of Noises (Italian: L'arte dei Rumori) is a Futurist manifesto written by Luigi Russolo in a 1913 letter to friend and Futurist composer Francesco Balilla Pratella. In it, Russolo argues that the human ear has become accustomed to the speed, energy, and noise of the urban industrial soundscape; furthermore, this new sonic palette requires a new approach to musical instrumentation and composition. He proposes a number of conclusions about how electronics and other technology will allow futurist musicians to "substitute for the limited variety of timbres that the orchestra possesses today the infinite variety of timbres in noises, reproduced with appropriate mechanisms".

The Art of Noises is considered by some authors to be one of the most important and influential texts in 20th-century musical aesthetics.

An experimental musical instrument (or custom-made instrument) is a musical instrument that modifies or extends an existing instrument or class of instruments, or defines or creates a new class of instrument. Some are created through simple modifications, such as cracked cymbals or metal objects inserted between piano strings in a prepared piano. Some experimental instruments are created from household items like a homemade mute for brass instruments such as bathtub plugs. Other experimental instruments are created from electronic spare parts, or by mixing acoustic instruments with electric components.

The instruments created by the earliest 20th-century builders of experimental musical instruments, such as Luigi Russolo (1885–1947),Harry Partch (1901–1974), and John Cage (1912–1992), were not well received by the public at the time of their invention. Even mid-20th century builders such as Ivor Darreg, Pierre Schaeffer and Pierre Henry did not gain a great deal of popularity. However, by the 1980s and 1990s, experimental musical instruments gained a wider audience when they were used by bands such as Einstürzende Neubauten and Neptune.