Musicology commonly classifies note scales as either hemitonic or anhemitonic. Hemitonic scales contain one or more semitones and anhemitonic scales do not contain semitones. For example, in Japanese music the anhemitonic yo scale is contrasted with the hemitonic in scale. The simplest scale in most common use over the planet, the atritonic anhemitonic ("Major") pentatonic scale, is anhemitonic, so also the whole tone scale.
A special subclass of the hemitonic scales is the cohemitonic scales. Cohemitonic scales contain two or more semitones (making them hemitonic), in particular such that two or more of the semitones fall consecutively in scale order. For example, the Hungarian minor scale in C includes F-sharp, G, and A-flat in that order, with semitones between.
Ancohemitonic scales, by contrast, possess either no semitones (and thus are anhemitonic), or possess semitones (being hemitonic) but ordered such that none are consecutive. In some uses, as vary by author, only the more specific second definition is understood. Examples are numerous, as ancohemitonia is favored over cohemitonia in the world's musics: diatonic scale, melodic major/melodic minor, Hungarian major, harmonic major scale, harmonic minor scale, and the so-called octatonic scale.
Scale or scales may refer to:
When referring to stringed instruments, the scale length (often simply called the "scale") is considered to be the maximum vibrating length of the strings to produce sound, and determines the range of tones that string is capable of producing under a given tension. In the classical community, it may be called simply "string length." On instruments in which strings are not "stopped" or divided in length (typically by frets, the player's fingers, or other mechanism), such as the piano, it is the actual length of string between the nut and the bridge.
String instruments produce sound through the vibration of their strings. The range of tones these strings can produce is determined by three primary factors: the mass of the string (related to its thickness as well as other aspects of its construction: density of the metal/alloy etc.), the tension placed upon it, and the instrument's scale length.
On many, but not all, instruments, the strings are at least roughly the same length, so the instrument's scale can be expressed as a single length measurement, as for example in the case of the violin or guitar. On other instruments, the strings are of different lengths according to their pitch, as for example in the case of the harp or piano.
The scale of a map is the ratio of a distance on the map to the corresponding distance on the ground. This simple concept is complicated by the curvature of the Earth's surface, which forces scale to vary across a map. Because of this variation, the concept of scale becomes meaningful in two distinct ways. The first way is the ratio of the size of the generating globe to the size of the Earth. The generating globe is a conceptual model to which the Earth is shrunk and from which the map is projected.
The ratio of the Earth's size to the generating globe's size is called the nominal scale (= principal scale = representative fraction). Many maps state the nominal scale and may even display a bar scale (sometimes merely called a 'scale') to represent it. The second distinct concept of scale applies to the variation in scale across a map. It is the ratio of the mapped point's scale to the nominal scale. In this case 'scale' means the scale factor (= point scale = particular scale).