# How do you build a Dominant 7th chord?

This is speaking in the key of E minor.

7th chords have always messed me up even when I think I have them right. For a dominant 7th you need 1, 3, 5, 7b, right? In E- I got E, G, B, C#. The 7b is supposed to be 1 note below 1 but I can't find where I went wrong.

• I’m sorry but in pedagogy this answer might be misleading and confusing, not just because it is less common seen in practice as compared to a Bm7 or B7 resolving to a Em, and also students can’t easily see and hear functionally the relationship in harmony. – Susanna Lau劉慧祺 Sep 10 at 3:54
• On the right of this site you see related questions and find learn the basics with music musictheory.net – Albrecht Hügli Sep 10 at 6:35
• So in dominant 7th chords you don't flatten the 7? I thought thats what it meant since it's supposed to be minor – Jinxed Sep 11 at 0:14

This is speaking in the key of E minor.

Reading this sentence I understand Em is the tonic.

In Em the V7 is B7 (b d# f# a).

Let’s assume you’re searching the V7 with the root E, which is the dominant7 of a-minor.

The term dominant 7 chord is implying that this is the major V7 of the tonic in any scale.

In your case (dom.7 =E7) the tonic (I) is A major and its parallel scale a-minor and the V7 is e g# b d.

The dominant7 chord is always a chord built of the 5th degree with the tones 1 - 3 - 5 - 7 with a major 3rd which is the leading tone to the tonic root.

In E- I got E, G, B, C#.

This chord is the Em6 as we have a minor 3rd (G) and c# is the 6th and not the 7th.

The 7b is supposed to be 1 note below 1 but I can't find where I went wrong.

Well, the 7b (1 note below 1) would be d and not c#.

You have to look up the scales, relative scale and parallel scale (natural and harmonic minor scales) and the triads to understand fully your problem. A good plan would be to notate the yourself as a ladder respecting the whole and half steps: first just as a scheme than notate in a staff system and drawing the pattern of a keyboard and guitar pattern and TAB. e.g. A and am (natural and harmonic scale) C and cm, E and em.

The best thing to start is to play some simple folksongs or spirituals with the chords.

Chord symbols are used to specify absolute intervals that are not related to any key or scale, and you can calculate the note pitches in semitones, regardless what "key" someone might be thinking about. E7 means: E - G# - B - D. In the key of C minor, E7 is E - G# - B - D, in the key of Bbbb, E7 is E - G# - B - D, in the key of Z semi-middle-sized, E7 is E - G# - B - D, etc. In any and every key, E7 is E - G# - B - D.

In semitones a dominant seventh chord (in root position) is:

• 0 (root)
• 4 semitones above root
• 7 semitones above root
• 10 semitones above root

in the key of E minor

Chord symbols are not in a key. E7 always has the exact same notes E - G# - B - D. This can be very nice, because you can accompany a song from chord symbols without knowing what keys or scales are being used by the melody or other players, as long as you stick to play only the notes that belong to the written chord symbol.

• All very well, except the 'semitones' bit. That'll get the right sound notes, but not always tell their names. So E7 is E Ab Cb Ebb?! – Tim Sep 10 at 9:49
• @Tim, for enharmonics (same pitch, different name), you would always use the letter name that corresponds to the interval. In the key of C, you would always count two letters over to get the third (E or Eb), even though the same pitches could be identified as D## and D# or Fb and Fbb. – kiprainey Sep 10 at 14:08
• I think talking about enharmonics just adds more confusion, because the point is to see that each chord symbol type specifies a very rigid interval structure where you don't have to care about the key or scale. The chord symbol E7 means E - G# - B - D, even if it's written on a staff with the key signature of F minor. Why complicate it any further? I might reconsider if the question is the other way, giving a chord symbol name for a group of dots. – piiperi Sep 10 at 14:40
• Exactly. Chords are defined by the semitones they occupy, not by the name those notes happen to have in a concrete key. Notes may have several names, and chords may have several names. But once you are told to play an F## (other name of the note G), you know exactly which note to play, and when you are told to play Cb7 chord, it's a simple matter of counting semitones to derive the exact notes, whatever their name (Cb-Ebb-Gb-Hbb, or just H-D-F#-A). – cmaster Sep 10 at 23:31

Strictly speaking, in any key, the dominant chord is that based on the V.

So, in key Em, the dominant chord will be B. Thus the dominant seventh will be B7.

Using the 'stacked thirds', as we do for a lot of chords, that gives us the notes B D♯ F♯ A. All of which are diatonic to the Em key and scale. Some people aren't too happy using 'diatonic' with relation to minors, but I think it works here.Bear in mind there are several different sets of notes that constitute minor keys.

If, however, you're talking about the 'dominant seventh' chord that usually takes things to the IV, that's different. Occasionally, it's used in key Em to arrive at IV (A/Am) and that has been covered in other answers. Although it's actually not what the question asks!

• I think "dominant seventh" can be taken as meaning chord type only. The OP was confused thinking that you're supposed to take the seventh note of the scale, which in the case of E minor is D, and because it's a dominant seventh, "flatten" it, giving C# or something. It becomes clearer if you just forget about scales and keys and diatonic anything. – piiperi Sep 10 at 10:49
• You do not need to start on V to build it, it occurs naturally in the Maj scale on the V. The formula is degree invariant, and that is its value. – ggcg Sep 10 at 17:45
• @ggcg - that's the point. There is only one 'dominant seventh' chord that can be built diatonically - that rooted on V. Of course it could be rooted anywhere, but that produces V/V, V/vi etc, and has to use a chromatic. – Tim Sep 11 at 9:50
• It seems incongruent with the OPs question. – ggcg Sep 11 at 10:27

If you’re building a E dominant 7th chord (notated as E7), the notes involved are E-G#-B-D.

Notice how are the ‘alphabets’ above are one note apart? That’s because chords are typically built by stacking in 3rds. The 7th of the E7 chord is by adding a 3rd above the 5th of the chord (ie. the B), it won’t be a C# or C anything, since a C is just a 2nd above B. And “D” is one whole tone below E.

However, if you are talking about constructing a diatonic dominant 7th chord in the key of E minor, that should be a B7 which consist of B-D#-F#-A. Notice again that “A” is one whole tone below B.

Hope this helps. :)

Update: I guess I should mention a couple of things more:

“Dominant” refers to a couple of things.

• First, it refers to the 5th degree of the scale. In the case of E minor, it refers to the B.
• Second, it refers to the function of the chord built on the 5th degree of the scale that resolves (pulls you) back to the tonic of the key. It’s commonly represented by the Roman numeral V7.
• Third, when we refer to a dominant 7th chord (or any related extensions), we refer to a specific chord type that must have a major 3rd and a b7, and be default a perfect 5th (which might be subjected to omission or alteration), ie 1-3-5-b7.

In minor key, the leading tone (ie. the 7th degree of the scale) is often raised when the chord is in dominant function.

• eg in E minor key, the notes are actually E F# G A B C D E
• a 5th degree 7th chord will be a Bm7 chord, which is B-D-F#-A.... you can use this chord, but......
• However, in practice, the D is very commonly raised in a dominant function chord when the V7 wants to resolve back to the I, ie instead of Bm7 you would raise the D to D# and have B7 (B-D#-F#-A) instead. This key gives a stronger pull toward the Em which composers often prefers.
• The D is however only raised in this case and not other functions, eg. when you want to build a chord from the 3rd degree “G”, the chord is a G major (G-B-D), D is not raised here.
• You should probably mention that you're not using the natural minor here. – Your Uncle Bob Sep 10 at 3:27
• Or rather, I should say that in minor key, the leading tone (the 7th degree note in the scale) is commonly raised in dominant function harmony, but not elsewhere. – Susanna Lau劉慧祺 Sep 10 at 3:29
• Still not exactly accurate! Using the notes from E harmonic minor (or E melodic minor) there's a leading note of D# already there. tha's one reason why those two scales exist. – Tim Sep 10 at 9:27

There are a couple possible issues that lead to confusion when applying the algorithm for constructing chords in key.

The first is proper name convention for the notes. In equal tempered tuning (standard fretted guitar, piano, etc) the C# and the Db are enharmonic. They are the exact same frequency and played the same way. For all intents and purposes they are the same. In just tuning they may not be. The letter names and degrees of the major scale for any key are related by a 1-to-1 correspondence. The letter names ALWAYS follow the sequence of the "musical alphabet" {A, B, C, D, E, F, G} repeat forever. For example to get the proper letter names for the E maj scale you simply take the sequence

{E, F, G, A, B, C, D, E}

Now these are just the proper "letter names". To make the maj scale you need to include the accidentals required to get the pattern of steps {W, W, H, W, W, W, H} between the notes (W = whole, H = half). This gives you,

{E, F#, G#, A, B, C#, D#, E}

Consider the 6th degree of the E maj scale. This is C# and NOT Db. Not simply because this key has sharps and not flats but because the letter name in the 6th position of the sequence is C. If you want to make an augmented 6th in the key of E you need to write Cx or C##. On an equal tempered instrument you will be playing D natural but you'd get points off a music theory test if you said that D natural is the aug 6th of E maj.

The second thing is the application of the formula for chords. As we build chords we always reference the formula to the major scale starting on the "One" or root of the chord. Even if you are in the key of C maj, when you build an A min chord you apply the formula to the A maj scale. The formulas are key independent, a few examples are provided below. X = any note,

X (or X maj) = {1, 3, 5}

X- (or X min) = {1, b3, 5}

X7 = {1, 3, 5, b7}

X-7(b5) = {1, b3, b5, b7}

You see the pattern. This formula may seem confusing if you know your modes. Some players may want to build a D-7 in the key of C and just say "why not use Dorian as the mode and say the formula is {1, 3, 5 ,7} of the Dorian mode". Well this would lead to a lot of ambiguity when it comes to describing the structure of chords independently of key or mode as you have the same construction in the Phrygian and Aeolian modes. And this brings us to the third possible point...

Third, there is a natural relationship between 7th chords in ANY key. In other words one can build a 7th chord on each note of the maj scale just as one can build one of the 7 diatonic modes starting at each of the 7 degrees of the maj scale. These are,

I maj7

ii -7

iii -7

IV maj7

V7

vi -7

vii -7(b5)

All these chords are in the same key, no accidentals required. This sequence is used to harmonize melodies in key and naturally contains features like resolution (V7-->I, contains the movement 7-->8, and 4-->3).

In general one is free to put any chord any where, which may violate the key you are in. For example, it is common in Jazz progressions for the vii chord to be a dom7 rather than a min7 (as would be "natural" in any key).

So when you say you are applying the formula for a chord in the key of Emin you have to ask yourself whether you are (1) trying to build a dom7 chord on the "tonic" of the key of Emin, or (2) trying to find the seventh chord that naturally occurs on the tonic of Emin, or (3) trying to find the V7 chord of Emin (as many have interpreted your question). If you are trying option 1 then the chord formula is independent of key (actually it always is). If you are trying option (3) then you walk up to the 5th note of the Emin scale and simply find what 7th chord is contained in the minor scale. By the way this would NOT be a dom7 chord if you use the natural minor scale it would be a -7 chord.

Now this brings us to the fourth point. There is no V7 chord in the minor scale. To create the feeling of a resolution in a minor key we alter the scale to create either harmonic minor (which has the natural or major 7th in it) or melodic minor (which has a maj 6 and 7 in the ascending pattern and min 6 and 7 in the descending pattern). Using these modes changes the 7th chords that are embedded in the minor key and creates the classic V7 --> I feel in that key (which may be expressed as V7-->i treating the "One" as the first note of the minor key).

It seems to me that you were trying to build a dom7 chord in E minor starting on E and applying the formula {1, 3, 5, b7} to the degrees of the minor key and this is simply not how the formula works. Applying this to a minor scale without respecting the relative intervals indicated in the formula would give {1, b3, 5, bb7}. Again, the formula for chords that you seem to be using is key and mode independent and is referenced to a Maj scale starting on the root.

Let's keep it simple:

An E dominant 7th (E7) chord is E G# B D.

In all cases, a dominant 7 chord consists of 1, Major 3, 5, and minor 7 relative to the root of the chord, regardless of what key the song is in.

Dominant also means the 5th note of the scale, and in most western music before jazz came along, that's where that kind of 7th chord was usually played, which is why it is called a dominant 7th. So for a song in E (major or minor), you would expect to play a dominant 7 chord starting on B, which would be B D# F# C.

• Hey @LeithMcCombs! Welcome to the site! I believe you meant "B D# F# A" for your B7 chord :) – WillRoss1 Sep 11 at 20:31