# For intervals, is three semitones major or minor?

It should be a pretty simple question, but under a bit of exam stress I have forgotten.

As the title says, is three semitones a major or minor interval?

Neither, 3 semi-tones is an augmented second.

It could also be a minor third.

I'm being a bit sarcastic, because the question was asked for a exam.

Intervals can be measured in semi-tones (or half steps.)

But, intervals are named by: first a number and second a quality.

The number is based on the count between notes of the musical pitch letters. A to C is a third. 1 for starting at A + the 2 steps up to C = 3, so it's would be a third... of some quality.

Determining the quality is a bit more complicated. Adding sharps or flats change the size of the interval in semi-tones. The basic interval number and size in semi-tones determines the quality. Several detailed charts are online at Wikipedia:

Starting on C, one semitone up is C#/Db, two is D, three is D#/Eb. If you choose to call it D#, it's an augmented 2nd. If you choose to call it Eb, it's a minor 3rd. (The latter is somewhat more likely, I think we'll agree)

• It could also be f-double-flat, so a doubly diminished fourth. Commented Nov 17, 2018 at 18:00
• @phoog I'd upvote any answer that listed every enharmonic spelling of this interval just to reward the effort that went into it Commented Nov 19, 2018 at 4:10

Three semitones, if it is a generic interval of a third, is a minor third. It could also be some other ugly enharmonic interval, like a triply-augmented unison.

• Perfectly ok answer. Why did you get a downvote? Jerks. Commented Nov 16, 2018 at 22:36

Major and minor are measured in intervals not tones so this can be hard to describe properly.

If starting on C imaging a piano keyboard, going up 3 semitones would be Eb. This would give the sound of a minor interval if we add a G above. If starting on A, 3 semitones down would be F# giving the sound of a Major interval if we add a D below. However, we only hear them as pairs of 2.

Giving it a 3rd note, another 3 semitone above Eb would give C, Eb, Gb is a Diminished sound.

0 semitone = C

1 semitone = C# / Db

2 semitone = C## / D / Ebb

3 semitone = D# / Eb / Fbb

As you can see, there are equivalents for these semitones. We know that 3 semitones from C going up can be:

D# (Augmented 2nd)

Eb (Minor 3rd)

Fbb (Doubly Diminished 4th)

These are all the same note, and sound the same but at different intervals.

Is three semitones major or minor?

If this really is a real exam question, the question is asking specifically for Minor or Major and not: perfect, augmented or diminished.

Since you can't make a Major interval from 3 semitones the answer HAS to be Minor as no starting note can produce a Major interval.

Update: 2018/11/17

To clear up for the 2 down votes and phoog's comment:

Ignoring intervals and focusing on sound alone, what do you hear? Visualise it on a keyboard:

If one was to play these two notes on a piano what would you hear? The answer would be "It sounds minor" then I tell you that you were wrong because it's actually augmented (or diminished). You would then argue "Why, it doesn't sound augmented or diminished".

Tones describes sound and intervals describe measurement. D#, Eb and Fbb all sound the same: C-D#, C-Eb and C-Fbb would all sound minor as a pair even though C-D# is an augmented 2nd and C-Fbb is a doubly diminished 4th.

To phoog's comment. Obviously yes, F# to A is always a minor 3rd, but 3 semitones above F# could be an augmented 2nd (G##) or a doubly diminished 4th (Bbb) which could form as part of a different chord (a major, augmented or diminished chord: C, Eb, G = C minor but Ab, C, Eb is Ab Major yet C, Eb, Gb is Diminished. Without intervals, it's too ambiguous to know what interval is used based on sound alone).

• The interval from F# to A is a minor third regardless of whether there is a D sounding below the F#. The major triad includes a minor third between the middle pitch and the upper pitch. Commented Nov 17, 2018 at 18:02
• What I mean was: Ignoring intervals, focus on sound. Add D below, the sound is Major (D major). Add C# above, it sounds minor (F# minor). If we have 2 note together you can't say if it's a minor or major sound unless it's built as a triad chord. 2 notes alone is ambiguous. The interval from F# to A will always be a minor 3rd, correct. Commented Nov 17, 2018 at 18:43