Scale (music) identified by using a binary system of twelve zeros or ones to represent each of the twelve notes of a chromatic scale. It is assumed that the scale is tuned using 12-tone equal temperament (so that, for instance, C is the same as D), and that the tonic is in the leftmost position. For example, the binary number 101011010101, equivalent to the decimal number 2773, would represent any major scale (such as C–D–E–F–G–A–B). This system includes scales from 100000000000 (2048) to 111111111111 (4095), providing a total of 2048 possible species, but only 351 unique scales containing from 1 to 12
Diatonic and chromatic tuned. Among this latter class, some instruments, such as the piano, are always tuned to a chromatic scale, and can be played in any key, while others are restricted to a diatonic scale, and therefore to a particular key. Some instruments, such as the harmonica, harp, and glockenspiel, are available in both diatonic and chromatic versions (although it is possible to play chromatic notes on a diatonic harmonica, they require extended embouchure techniques, and some chromatic notes are only usable by advanced players). Because "diatonic scale" is itself ambiguous, distinguishing intervals is also ambiguous. For example, the interval B–E (a