Major scale will generally reflect the accidentals in the corresponding major scale. For instance, if a piece of music is in E major, then the seven pitches in the E major scale (E, F, G, A, B, C and D) are considered diatonic pitches, and the other five pitches (E, F/G, A, B, and C/D) are considered chromatic pitches. In this case, the key signature will have three flats (B, E, and A). The figure below shows all 12 relative major and minor keys, with major keys on the outside and minor keys on the inside arranged around the circle of fifths.
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