Is this ALWAYS a dominant 7th?

**bassybill** · #1 09-08-2009, 04:15 AM

I seem to have seen an increased usage of the phrase "dominant 7th" to describe just about any instance of a chord with root, maj3, perfect5, minor7, such as G7 (GBDF).

I would only call G7 a dominant 7th if it appeared in the context of the key of C. When it crops up as a (non-diatonic) chord in any other key, I'd just call it "a seventh" as that always means root, maj3, perfect5, minor7 to me, unless specified otherwise.

Dominant 7th has always had a much more specific meaning for me than just any example of this sort of chord.

So, what's your take? Your thoughts are welcome.

mvw356 · #2 09-08-2009, 04:25 AM

i thought 'dominant 7' was another way for saying major 7th

.

when i think about chords like that i leave the key out of the equation altogether as most of these weird dom dim 7th/9th 11th/13th chords in a progression of chords don't really fit a particular key.

ok, so i reread your post, why would you call the Chord GBDF G7? i thought it is Gmin7 or Gdim7? confusing this....

Bruce Lindfield · #3 09-08-2009, 04:33 AM

In Jazz theory I have been taught, the dominant is the chord built on the 5th note of the major scale.

In Jazz you can have "secondary dominants" - where they appear out of place...? It's a bit more complicated than that - but google "secondary dominant chords" and you should get a full explanation - rather than me typing it all out!!

JtheJazzMan · #4 09-08-2009, 04:35 AM

I seem to have seen an increased usage of the phrase "dominant 7th" to describe just about any instance of a chord with root, maj3, perfect5, minor7, such as G7 (GBDF)

Yep sounds fine to me, no confusion if someone tells me to play a dom 7 chord

G7 in the key of C major could be described as the "dominant of C major".

But its not specialised terminology.

**bassybill** · #5 09-08-2009, 05:45 AM

Quote:

Originally Posted by mvw356

i thought 'dominant 7' was another way for saying major 7th

.

when i think about chords like that i leave the key out of the equation altogether as most of these weird dom dim 7th/9th 11th/13th chords in a progression of chords don't really fit a particular key.

ok, so i reread your post, why would you call the Chord GBDF G7? i thought it is Gmin7 or Gdim7? confusing this....

Useful link for you:

http://en.wikipedia.org/wiki/Chord_notation#Sevenths

Also:

jazz theory/sight reading homework

**bassybill** · #6 09-08-2009, 05:49 AM

Quote:

Originally Posted by Bruce Lindfield

In Jazz theory I have been taught, the dominant is the chord built on the 5th note of the major scale.

In Jazz you can have "secondary dominants" - where they appear out of place...? It's a bit more complicated than that - but google "secondary dominant chords" and you should get a full explanation - rather than me typing it all out!!

Yep, that seems correct - G7 is dominant in C and a secondary dominant in other keys.

http://musictheoryresources.com/members/FA_sec_dom.htm

Thanks Bruce. This isn't a term I have heard before.

Asher S · #7 09-08-2009, 05:54 AM

Here's an older post of mine that might help clarify chord nomenclature.

Quote:

Originally Posted by Asher S

A little about CHORDS
the basic triad consists of the root (1), third (3), and fifth (5).

To understand major vs minor, and "perfect" vs diminished vs augmented, you should know that in the 8-note scale (including the octave), only the 4 and 5 can be diminished (flattened a half tone). All the other notes (2, 3, 6, 7) are "minor" when flattened a half tone. Sharpening a half tone yields an augmented "X" (2-7).

So, with this in mind, and using the C Ionian scale (C D E F G A B C) the main triads are:

MAJOR: C E G
MINOR: C Eb G
DIMINISHED: C Eb Gb
AUGMENTED: C E G#

Now, if you add in a fourth note to the chord (commonly the 7th) you need to know that in the notation, one "maj" refers to the 7th being major (a half-tone below the octave) and one "min" (or just "m") refers to the 3rd (being flat). The 3rd default is MAJOR and the 7th default is MINOR... SO:

C Maj 7: C E G B (C major triad + major 7th: B is a half-tone below C)
C Dominant 7 (Or just C7) : C E G Bb (C major triad + minor 7th)
C min 7: C Eb G Bb (C minor triad + minor 7th)
C Diminished 7: C Eb Gb Bbb (C diminished with double flat B, which is equivalent to an A)
C Minor Major 7: C Eb G B (C minor triad + major 7)

Then you can get into 6ths, 9ths, 11ths, 13ths, sus4 etc etc...

A good book that explains this (and much more) is the Total Jazz Bassist by Overthrow & Ferguson.

I hope that helps.

**bassybill** · #8 09-08-2009, 06:15 AM

^^^ Thanks for that - will be useful to a lot of folks, I'm sure.

It made me smile as it's so similar to the post I linked to earlier:

jazz theory/sight reading homework

Great minds, and all that.

Asher S · #9 09-08-2009, 06:23 AM

Quote:

Originally Posted by bassybill

^^^ Thanks for that - will be useful to a lot of folks, I'm sure.

It made me smile as it's so similar to the post I linked to earlier:

jazz theory/sight reading homework

Great minds, and all that.

Ahh- sorry about that. I was in a rush and didn't read through all the responses!

**bassybill** · #10 09-08-2009, 06:26 AM

Quote:

Originally Posted by Asher S

Ahh- sorry about that. I was in a rush and didn't read through all the responses!

No problem - there was some additional info in yours anyway.

mvw356 · #11 09-08-2009, 06:28 AM

Quote:

Originally Posted by bassybill

Useful link for you:

http://en.wikipedia.org/wiki/Chord_notation#Sevenths

Also:

jazz theory/sight reading homework

thanks for that

Alvaro Martín Gómez A. · #12 09-08-2009, 02:02 PM

There are 7th chords that don't have a dominant function. Basically, for a 7th chord to be considered as "dominant", it must be a major chord with a minor seventh.

The presence of the major third plus the minor seventh creates a tritone interval, which is the one that creates that "need for resolution" (tension-release). Any other 7th chord (i.e. Maj7, min7) isn't considered as "dominant" because of the absence of the tritone. Non-dominant 7th chords are also resolved, but that's more because of voice leading than tension-release.

derekd · #13 09-08-2009, 02:32 PM

While I understand the distinction, on the bandstand, the term dominant 7 is gonna be used, in my experience. We can talk about the functionality of sub dominants and the blues or jazz, but in practical terms, I don't often see this distinction made outside of the classroom or in books.

Am I alone on this?

Bruce Lindfield · #14 09-09-2009, 08:53 AM

It does make a difference if you are looking at a tune or section of a tune, as being in one particular key and are intent on just playing notes from that key...?

As soon as you see a 7th chord that is not within the key then you introduce a sound and notes that are not from that key - even if only for half a bar - the piece has effectively shifted key! If you don't take acount of that in some way, then you just aren't playing the piece as written or intended...

If you don't acknowledge what is happening - then it is effectively, just a mistake on your part!

EADG mx · #15 09-19-2009, 06:36 PM

Quote:

Originally Posted by mvw356

i thought 'dominant 7' was another way for saying major 7th

.

when i think about chords like that i leave the key out of the equation altogether as most of these weird dom dim 7th/9th 11th/13th chords in a progression of chords don't really fit a particular key.

ok, so i reread your post, why would you call the Chord GBDF G7? i thought it is Gmin7 or Gdim7? confusing this....

Major 7th

1 3 5 7
C E G B

Dominant 7th or just "7th"

1 3 5 b7
C E G Bb

While they only differ in one note, the one pitch makes all of the difference in terms of the chord's function and tonal gravity (or lack thereof). I can get into that, but that much information will get you through a chart in the meantime.

Michael Case · #16 09-19-2009, 07:11 PM

In the key of C major a G7 is the dominant 7th yes. That same G7 chord would still be a dominant chord and another key although it would be called a secondary dominant. Take the bridge for "rhythm changes" in the key of Bb:

D7 for two bars to G7 for two bars to C7 for two bars to F7 for two bars.

Now the D7 is a dominant for G7 which is the dominant for C7 which is the dominant for F7 which brings us back to Bb Major 7.

A secondary dominant is a dominant that leads to another chord in the song. Sometimes the chord the SD is leading to can be in the original key sometimes not.

ForestThump · #17 09-19-2009, 07:22 PM

As I understand it:

A D7 is always a dominant chord since it is built with diatonic tones from the key of G major or notes from D mixolydian mode.
A dominant chord as I understand it is a major7th chord with a flatted 7th.

EADG mx · #18 09-20-2009, 06:39 PM

Is G7 a dominant 7th chord in the mode of G Mixolydian?

Would it not be then functioning as the tonic?

Michael Case · #19 09-20-2009, 06:44 PM

Quote:

Originally Posted by EADG mx

Is G7 a dominant 7th chord in the mode of G Mixolydian?

Would it not be then functioning as the tonic?

Are you referring to something like the blues? Then yes G7 would then be the tonic, but in general it is a dominant function.

WalterBush · #20 09-20-2009, 06:55 PM

As I was taught, a dominant chord is one built off the fifth note in any given scale.

A dominant 7th simply means a flatted 7th chord built from the fifth note of a scale. Depending on what key, scale, or mode you're using, you could just as easily refer to a dominant major 7th or dominant minor 7th chord. The word "dominant" refers to the position of a chord's root note in a scale, not to the notes in the chord itself.

If I'm wrong, please point out how.