A lot vs. Alot: 9 Grammatical Pitfalls
in the system of equal temperament tuning used on keyboard instruments, two tones that sound the same but are notated (spelled) differently. Pitches such as F and G are said to be enharmonic equivalents; both are sounded with the same key on a keyboard instrument. The same is true of intervals, which are always named according to their notation: A-F is an augmented sixth, while A-G and G-F are both minor sevenths; all are enharmonically equivalent. C major (which has a key signature with seven sharps) and D major (with five flats) are enharmonically the same key; D major is considered easier to read and thus is much more commonly used than C major. Enharmonic tones and intervals are often components of pivot chords in modulation (change of key), especially if the composer is changing from a key notated in flats to one notated in sharps (or vice versa).