The viola (/viˈoʊlə/; Italian pronunciation: [viˈɔːla]) is a string instrument that is bowed or played with varying techniques. It is slightly larger than a violin and has a lower and deeper sound. Since the 18th century, it has been the middle or alto voice of the violin family, between the violin (which is tuned a perfect fifth above) and the cello (which is tuned an octave below). The strings from low to high are typically tuned to C3, G3, D4, and A4.
In the past, the viola varied in size and style, as did its names. The word viola originates from Italian. The Italians often used the term: "viola da braccio" meaning literally: 'of the arm'. "Brazzo" was another Italian word for the viola, which the Germans adopted as Bratsche. The French had their own names: cinquiesme was a small viola, haute contre was a large viola, and taile was a tenor. Today, the French use the term alto, a reference to its range.
The viola was popular in the heyday of five-part harmony, up until the eighteenth century, taking three lines of the harmony and occasionally playing the melody line. Music for the viola differs from most other instruments in that it primarily uses the alto clef. When viola music has substantial sections in a higher register, it switches to the treble clef to make it easier to read.
The viola often plays the "inner voices" in string quartets and symphonic writing, and it is more likely than the first violin to play accompaniment parts. The viola occasionally plays a major, soloistic role in orchestral music. Examples include the symphonic poems Don Quixote by Richard Strauss and Harold en Italie by Hector Berlioz. In the earlier part of the 20th century, more composers began to write for the viola, encouraged by the emergence of specialized soloists such as Lionel Tertis and William Primrose. English composers Arthur Bliss, York Bowen, Benjamin Dale, Frank Bridge, Benjamin Britten and Ralph Vaughan Williams all wrote substantial chamber and concert works. Many of these pieces were commissioned by, or written for Lionel Tertis. William Walton, Bohuslav Martinů, Toru Takemitsu, Tibor Serly, Alfred Schnittke, and Béla Bartók have written well-known viola concertos. Paul Hindemith, who was a violist, wrote a substantial amount of music for viola, including the concerto Der Schwanendreher. The concerti by Paul Hindemith, Béla Bartók, and William Walton are considered the "big three" of viola repertoire.
AudioLayer satisfies the most sought after gap for contemporary music production on iOS devices. AudioLayer is a full featured open standard audio multi-sampler pushing the boundaries beyond what has been available even in the desktop music production worlds. And all this integrated in all relevant iOS production environments especially the emerging AUv3 AudioUnit standard.