become increasingly filled with the noise of machines, encouraging musicians to create a more "complicated polyphony" in order to provoke emotion and stir our sensibilities. He notes that music has been developing towards a more complicated polyphony by seeking greater variety in timbres and tone colors. Noise-Sounds Russolo explains how "musical sound is too limited in its variety of timbres." He breaks the timbres of an orchestra down into four basic categories: bowed instruments, metal winds, wood winds, and percussion. He says that we must "break out of this limited circle of sound and conquer the infinite variety of noise-sounds," and that technology would allow us to manipulate noises in ways that could not have been done with earlier instruments. Future sounds Russolo claims that music has reached a point that no longer has the power to excite or inspire. Even when it is new, he argues, it still sounds old and familiar, leaving the audience "waiting for the extraordinary sensation that never comes." He urges musicians to explore the city with "ears more sensitive than eyes," listening to the wide array of noises that are often taken for granted, yet (potentially) musical in nature. He feels this noise music can be given pitch and "regulated harmonically," while still preserving irregularity and character, even if it requires assigning multiple pitches to certain noises. The variety of noises is infinite. If today, when we have perhaps a thousand different machines, we can distinguish a thousand different noises, tomorrow, as new machines multiply, we will be able to distinguish ten, twenty, or thirty thousand different noises, not merely in a simply imitative way, but to combine them according to our imagination. Six Families of Noises for the Futurist Orchestra Russolo sees the futurist orchestra drawing its sounds from "six families of noise": Roars, Thunderings, Explosions, Hissing roars, Bangs, Booms Whistling, Hissing, Puffing Whispers, Murmurs, Mumbling, Muttering, Gurgling Screeching, Creaking, Rustling, Buzzing, Crackling, Scraping Noises obtained by beating on metals, woods, skins, stones, pottery, etc. Voices of animals and people, Shouts, Screams, Shrieks, Wails, Hoots, Howls, Death rattles, Sobs Russolo asserts that these are the most basic and fundamental noises, and that all other noises are only associations and combinations of these. He built a family of instruments, the Intonarumori, to imitate these six kinds of noises. Conclusions Russolo includes a list of conclusions: Futurist composers should use their creativity and innovation to