How note names are chosen

A note has a letter as well as a pitch

The written name contains information that a piano-key location alone cannot show. C-sharp and D-flat reach the same key in equal temperament, but they use different letters. Those letters affect the names of intervals and the way a chord or scale is read.

ChordLilt keeps spelling in context. A chord built on C uses E or an altered E for its third. A seven-note diatonic scale uses each letter once before repeating the tonic at the octave.

Check three spellings that can look surprising

F-sharp major contains F-sharp, G-sharp, A-sharp, B, C-sharp, D-sharp and E-sharp. E-sharp sounds on the F key, but the E letter is required for the seventh degree.

D-flat dominant seventh is D-flat, F, A-flat and C-flat. Calling the last note B would hide its written relationship as a seventh. C diminished seventh similarly uses B-double-flat as its seventh; A is its enharmonic piano-key name, not its chord-degree spelling.

Enter a complete note

Use a letter from A through G, an accidental when needed, and an octave for a specific pitch. For example, F-sharp4 can be entered as F#4 or F♯4, and B-flat3 as Bb3 or B♭3. Use the actual note field’s example as a guide.

An octave belongs to the written note, so unusual accidentals near B and C deserve care. B-sharp3 sounds like C4; C-flat4 sounds like B3. Keeping the written octave avoids changing the intended interval when a note crosses that boundary.

Do not infer one root from an ambiguous set

The pitches C, D and G can be read as C suspended second or G suspended fourth. A set of pitch classes does not supply enough context to establish one harmonic root. Review the listed candidates and choose the interpretation that fits your exercise.

Likewise, a sharp-or-flat preference for a chromatic keyboard is not a complete spelling rule for every key. Check the chosen root, quality and degree labels before using the result as notation.

Use the written and sounding views together

When a name looks unfamiliar, compare three things: its letter, its semitone distance from the root and its diagram position. Agreement among all three is more useful than changing the accidental until the label looks familiar.

1. Read the root and the intended degree.
2. Count letter names for the interval number.
3. Check semitone distance for the interval quality.
4. Keep the resulting spelling in your saved or printed reference.