Why is F sometimes called E#?
A contribution by Nemesio Valle, III
Although tones ostensibly have a discrete pitch (i.e., frequency), how they are "spelled" is elemental to their interpretation. For example, both Eb and D# above middle C utilize a frequency of about 622 Hz on an equally-tempered keyboard, but how they function (i.e., are treated musically) are very different. Such distinction is informed by the underlying grammar of Western Music.
When trying to understand how such enharmonic tones are discerned, one must understand the basic guiding principles for scalar construction. Because scale degrees form the roots of different triads, (each of which has a different "grammatical" usage in the musical sentence) each must have a distinct letter associated with it. For example, a D major scale will have an F# as its third scale degree since "F" is the third letter in a sequence that begins on "D." The use of "Gb" in its stead, would be musically unintelligible to the reader of a musical score because "G" implies a function based on the fourth scale degree. This treatment remains intact even in unorthodox scales (or "modes"); e.g., a Lydian scale (with a raised fourth scale degree) would be spelled: D, E, F#, G#, A, B, C#, D. The major scale which begins on Gb, if properly spelled, must use the letter "C" as its fourth scale degree, thus Gb, Ab, Bb, Cb, Db, Eb, F, Gb, even though the tone associated with that pitch is more commonly spelled "B." Similarly, in the little-used key of C# major, the notes used are C#, D#, E#, F#, G#, A#, B#, C#, even though the third and seventh scale degrees are most often written "F" and "C" respectively. Consistency in such nomenclature and usage is as important to the musician as spelling and grammar is to the journalist.
Just as we expect nouns and verbs to be used in particular ways, the spelling of a given tone gives information to the performer about how it will function. A musician will expect the fourth tone in a chord spelled C, E, G, Bb to be treated in a particular manner (i.e., as the seventh of a V7 chord, and consequently resolve downwards to A). An A# in such a context would result in a different resolution (i.e., as the augmented 6th of a German Sixth chord, which would resolve upwards to B). Of course, like language, expectations can be quite plastic; just as we might use the pun, homonym, or double entendre, a chord might be spelled (and then treated) differently in successive iterations. Such application can be used with great effect in order to create ambiguity (and thereby tension) for the listener. Because the listener cannot know how a particular pitch is spelled until after it is resolved, such "respelling" and movement into unexpected harmonic directions creates an a posteriori "a-ha" moment in which the listener reinterprets the chord from what was expected to what actually transpired. This compositional device can be used to create brief but unexpected harmonic deviations or provide a springboard for full-blown modulation into more distantly related keys.
Explore this concept further on the Scale-Key Relationships page.
Copyright 2009 Richard Romanelli