Music

Music is an art form and cultural activity whose medium is sound and silence. The common elements of music are pitch (which governs melody and harmony), rhythm (and its associated concepts tempo, meter, and articulation), dynamics (loudness and softness), and the sonic qualities of timbre and texture (which are sometimes termed the "color" of a musical sound). Different styles or types of music may emphasize, de-emphasize or omit some of these elements. Music is performed with a vast range of instruments and with vocal techniques ranging from singing to rapping, and there are solely instrumental pieces, solely vocal pieces and pieces that combine singing and instruments. The word derives from Greek μουσική (mousike; "art of the Muses"). In its most general form, the activities describing music as an art form include the production of works of music (songs, tunes, symphonies, and so on), the criticism of music, the study of the history of music, and the aesthetic examination of music. Ancient Greek and Indian philosophers defined music as tones ordered horizontally as melodies and vertically as harmonies. Common sayings such as "the harmony of the spheres" and "it is music to my ears" point to the notion that music is often ordered and pleasant to listen to. However, 20th-century composer John Cage thought that any sound can be music, saying, for example, "There is no noise, only sound."

Classical music

Classical music is art music produced or rooted in the traditions of Western music, including both liturgical (religious) and secular music. While a similar term is also used to refer to the period from 1750-1820 (the Classical period), this article is about the broad span of time from roughly the 11th century to the present day, which includes the Classical period and various other periods. The central norms of this tradition became codified between 1550 and 1900, which is known as the common practice period. The major time divisions of classical music are as follows: the early music period, which includes the Medieval (500–1400) and the Renaissance (1400–1600) eras; the Common practice period, which includes the Baroque (1600–1750), Classical (1750–1820), and Romantic eras (1804–1910); and the 20th century (1901–2000) which includes the modern (1890–1930) that overlaps from the late 19th-century, the high modern (mid 20th-century), and contemporary or postmodern (1975–2015) eras.

Concentration

In chemistry, concentration is the abundance of a constituent divided by the total volume of a mixture. Several types of mathematical description can be distinguished: mass concentration, molar concentration, number concentration, and volume concentration. The term concentration can be applied to any kind of chemical mixture, but most frequently it refers to solutes and solvents in solutions. The molar (amount) concentration has variants such as normal concentration and osmotic concentration.

Qualitative description

Often in informal, non-technical language, concentration is described in a qualitative way, through the use of adjectives such as "dilute" for solutions of relatively low concentration and "concentrated" for solutions of relatively high concentration. To concentrate a solution, one must add more solute (for example, alcohol), or reduce the amount of solvent (for example, water). By contrast, to dilute a solution, one must add more solvent, or reduce the amount of solute. Unless two substances are fully miscible there exists a concentration at which no further solute will dissolve in a solution. At this point, the solution is said to be saturated. If additional solute is added to a saturated solution, it will not dissolve, except in certain circumstances, when supersaturation may occur. Instead, phase separation will occur, leading to coexisting phases, either completely separated or mixed as a suspension. The point of saturation depends on many variables such as ambient temperature and the precise chemical nature of the solvent and solute.

Instrumental

An instrumental is a musical composition or recording without lyrics, or singing, although it might include some inarticulate vocal input; the music is primarily or exclusively produced by musical instruments.

In a song that is otherwise sung, a section not sung but played with instruments can be called an instrumental interlude. If the instruments are percussion instruments, the interlude can be called a percussion interlude. These interludes are a form of break in the song.

In popular music

In commercial popular music, instrumental tracks are sometimes renderings of a corresponding release that features vocals, but they may also be compositions originally conceived without vocals. An instrumental version of a song which otherwise features vocals is also known as a -1 (pronounced minus one).

The opposite of instrumental music is a cappella.

For genres in which a non-vocal song or interlude is conceived using electronic media, rather than with true musical instruments, the term instrumental is nonetheless used for it.

Alpha Waves

Alpha Waves is an early 3D game that combines labyrinthine exploration with platform gameplay. By most definitions of the genre it could be considered to be the first 3D platform game, released in 1990, 6 years before Super Mario 64. Alpha Waves was released one year before Hovertank 3D, which is sometimes incorrectly credited as being the first 3D game on the PC. It provided the first truly immersive 3D experience, combining for the first time full-screen, six-axis, flat-shaded 3D with 3D object interaction (like bouncing on a platform). Alpha Waves was an abstract game with a moody, artistic presentation, curiously named for its supposed ability to stimulate the different emotional centers of the brain with its use of color and music.

It was developed initially for the Atari ST by Christophe de Dinechin, and later ported to the Amiga and DOS. The DOS port was done by Frédérick Raynal, a notable game designer who would go on to develop Alone in the Dark (often abbreviated AitD), and Little Big Adventure. He has said that his work on Alpha Waves was a major inspiration for the 3D engine for Alone in the Dark. The PC version was also localized in North America by Data East, and retitled Continuum. Infogrames may have also published their own version in the US under the original title, and it was also released as a part of no less than two Infogrames compilations, on which it retained its original name.