How to Read Plus and Minus Signs in Chord Symbols

In a symbol such as C−, the minus sign identifies a minor chord. Its notes are C–E♭–G: root, minor third, and perfect fifth. Compare that with C major, C–E–G. The third changes; the fifth stays the same. MusicXML defines these major and minor chord structures explicitly. kind-value data type — MusicXML 4.0

You may see the same C minor chord written as Cm, Cmin, or C−. The minus is an alternative chord-quality label, so there is no instruction to subtract a note. Read the symbol aloud as “C minor.” The MusicXML reference documents the minus convention, while Steinberg’s notation manual lists m, min, and mi as minor-quality entries. MusicXML chord-quality symbols, Chord Symbol Popover Reference — Cubase Pro 15.0

As a practical reading habit, translate the sign into a word before choosing notes: D− becomes “D minor,” and A− becomes “A minor.” This keeps a small dash from becoming an isolated instruction whose target you have to guess.

A plus sign used as the chord quality means augmented. An augmented triad contains a root, major third, and augmented fifth. For C, that gives C–E–G♯. Start with C major and raise its fifth, G, by one semitone. Steinberg lists + and aug as augmented-quality entries, and MusicXML specifies the underlying intervals. Cubase chord-quality reference, MusicXML chord structures

Symbol	Read aloud	Notes	Change from C major
C	C major	C–E–G	None
C− or Cm	C minor	C–E♭–G	Lower the third
C+ or Caug	C augmented	C–E–G♯	Raise the fifth

These note spellings are worked applications of the interval definitions above. Notice that plus and minus change different chord members here: the augmented quality changes the fifth, while the minor quality changes the third. Memorizing that distinction is more useful than treating the signs as opposite operations on one note.

Read the chord quality and the seventh separately. A minor-seventh chord consists of a minor triad with a minor seventh; an augmented-seventh chord consists of an augmented triad with a minor seventh. A major-seventh chord has a major triad with a major seventh. kind-value data type — MusicXML 4.0

Applying those definitions produces this comparison:

Symbol	Meaning	Notes
C7	C dominant seventh	C–E–G–B♭
C−7 or Cm7	C minor seventh	C–E♭–G–B♭
C+7	C augmented seventh	C–E–G♯–B♭
Cmaj7	C major seventh	C–E–G–B

In particular, C+7 does not mean C major seventh. The plus identifies the augmented triad, and the plain 7 supplies the minor seventh. The University of Puget Sound’s theory text explicitly explains this reading. Jazz Chord Basics

For a useful comparison at an instrument, play C7, then C−7, then C+7, using the notes in the table. Keep C and B♭ in place. Change E to E♭ for the minor chord, then return to E and change G to G♯ for the augmented chord. This turns the symbols into specific note choices.

Some notation uses plus and minus as alternatives to sharp and flat signs in chord alterations. A clearly grouped (+11) means raise the eleventh, and (−9) means lower the ninth. Parentheses help show which number the sign affects. Jazz Chord Basics

For example, interpret C7(−9) by building C7 first: C–E–G–B♭. The ordinary ninth above C is D; lowering it by one semitone gives D♭. The resulting spelling is C–E–G–B♭–D♭, which you can write more explicitly as C7(♭9).

Similarly, C7(+11) raises the ordinary eleventh, F, to F♯. An illustrative voicing is C–E–B♭–F♯. This voicing leaves out the perfect fifth; it demonstrates the alteration without attempting to place every possible chord member under your fingers. Antonio J. García’s original notation guide permits sharp/flat signs in place of plus/minus alterations and discusses omitting natural fifths. Clear Chord Symbols

Keep these two readings distinct: C−7 names a minor-seventh chord, whereas C7(−9) names a dominant-seventh chord with a lowered ninth. Identify the whole chord structure before applying a local alteration.

Chord-symbol conventions vary. García’s guide notes the limited universal agreement and the practical difficulty of reading a small dash accurately. The Puget Sound text recommends grouping altered numbers to clarify what a sign affects. A cramped symbol without clear grouping may therefore need more evidence than its character order alone supplies. Clear Chord Symbols, Jazz Chord Basics

Use this checking sequence when the intended grouping is unclear:

1. Check the chart’s notation key. Look for an explanation of chord symbols in the score or collection.
2. Compare clearer symbols on the same chart. See whether minor chords consistently use a dash and alterations use parentheses.
3. Inspect any written accompaniment or chord diagram. Compare its actual notes with the competing readings.
4. Write the alternatives out. Seeing exactly which notes differ makes the unresolved question concrete.
5. Confirm the reading when possible. If the available notation does not settle it, keep your interpretation provisional.

When making a rehearsal copy, expand a confirmed reading into Cm7, Caug7, or C7(♭9). This gives you a readable reminder without repeatedly decoding the same mark.

Use a four-pass reading method: root, quality, numbered structure, alterations. The following worked example applies the minor-seventh definition and the numbered-alteration convention to D−7(−5). García’s guide also shows minor chords with a separately lowered fifth. MusicXML chord structures, Clear Chord Symbols

1. Find the root: D.
2. Read the quality: the first minus means minor, giving D–F–A.
3. Read the seventh: add C, producing D–F–A–C.
4. Apply the separate alteration: (−5) lowers A to A♭, producing D–F–A♭–C.

A clearer equivalent is Dm7(♭5). Both signs now have an explicit job: one establishes the minor quality; the other lowers the fifth. This example is especially useful because it prevents the mistaken habit of assigning every minus sign the same meaning.

For the next unfamiliar chord, write its root and basic chord notes before changing anything. Then apply each remaining mark to its stated target. Once you can identify the changed third, fifth, or extension, the symbol becomes a compact set of playable instructions.

• The <kind> element — MusicXML 4.0
• kind-value data type — MusicXML 4.0
• Chord Symbol Popover Reference — Cubase Pro 15.0
• Jazz Chord Basics — Music Theory for the 21st-Century Classroom
• Clear Chord Symbols — Antonio J. García