Dominant 5ths

Ok i saw this argument on another forum and i wanted to clear up the confusion it caused me.

When we say 'dominant' are we talking about the chord built on the 5th degree or any major chord with a b7? I was alos told that the common blues progression isnt all dominants at all. E.g A7, D7 E7 arent all dominants.

Frankly i always thought of dominant chords as being those major chords with a flat 7th. Also if a person came up to me and asked me to play the dominant in, say C maj, do i play the Gmaj or G7th?

Thanks a lot and i hope this isnt too much of a newb question, i honeslty thought i had gotten my theory down. :(

Hi, my knowledge of musical theory is limited, but I know a dominant chord is one built on the fifth degree of a given scale. A dominant 7th would be same except with a b7.

its all semantics, idont really understand it my self but i think (i am probably wrong) dominants are just a name for a chord. Like u have maj7 which also has a 5th note in it and u have a dominant 7 which also has a fifth. i dont think its refering to the actual notes themselves.

btw domiant 7ths are the blues chords.

I thought the dominant was just the 5th degree of the scale.

Originally Posted by: FireAndIce24i dont think its refering to the actual notes themselves.

Yes, it is reffering to the actual notes.

To the threadstarter, a dominant seventh chord is naturally build on the 5th degree of the major scale, but it can be played in other places. A dominant chord has a Root, 3rd, 5th (not essential), and a flat 7th.

Also if a person came up to me and asked me to play the dominant in, say C maj, do i play the Gmaj or G7th?

If they asked that, you would play G7. If they just asked for the 5th in C, play the regular G.

E.g A7, D7 E7 arent all dominants.

Well, yes, they are all dominants. They may not necessarily fit in one key, but with the 7 after the chord name, you know it's a dominant chord.

When you see a progression that goes something like E7 A7 B7, you are actually switching keys all the time. There is only one natural dominant seventh in a key. In the key of E, that would be the B7. But the E7 and A7 are not in key. To solo over a progression like that theoretically correctly, you would solo in E, A, and B Mixolydian, depending on what chord is currently being voiced. For the E7, you would play in E Mixo, when the A7 comes up, you would go to A Mixo, and when the B7 shows up, B Mixo.

This is because the Mixolydian mode is the 5th mode in the major scale, and the dominant 7th is built on the 5th degree.

The reason I say "theoretically correctly" is because most blues songs that you see that chord progression in is simply soloed over in Em Pentatonic, which works as well, but is not technically theoretically sound. But hey, it works.

the dom is the 5th like 5th of the 1 4 5 progression. and the 6th is the relative minor.

Dominant chords are a 'family' of chords...there are essentially three families...Major, Minor, and a bit of both...Dominant. Beyond that there are other chord types...diminished, augmented, sus, etc...

The V chord of key just happens to be built to a 7th chord. It's the fact that it's the V chord that forces it back to the one, not the fact that it can be built with the b7.

It's evident in the 'b5 substitution' when they say 'a Dominant chord can be substituted with a another Dominant chord a b5th above it'.

That substitute chord is not the V of the key, but it is still a Dominant chord.

Also, in chord formula's they are not concerned with the key or the V, or whatever...they are concerned with the fact that a Dominant chord, or the Dominant family, is built with a 1 3 5 b7.

Again, the V chord of a key just happens to be built with a b7.

Originally Posted by: ZamboniYes, it is reffering to the actual notes.

To the threadstarter, a dominant seventh chord is naturally build on the 5th degree of the major scale, but it can be played in other places. A dominant chord has a Root, 3rd, 5th (not essential), and a flat 7th.

but its a fifth. its ALWAYS going to be a perfect fifth meaning its always going to be 7 frets away. in every scale and every chord. theres no major or minor 5th. there a tritone (flat five/sharp 4) but thats not what were talking about.

Originally Posted by: FireAndIce24but its a fifth. its ALWAYS going to be a perfect fifth meaning its always going to be 7 frets away. in every scale and every chord. theres no major or minor 5th. there a tritone (flat five/sharp 4) but thats not what were talking about.

What are you talking about? A dominant chord is built on the fifth degree of the major scale. And there is not necessarily a fifth in the chord.

I don't know where you came up with the major or minor 5th thing, no one said anything about that...

Edit: I see what you're referring to, your previous post. Most chords DO have a fifth in it, that doesn't mean that it has to be explicitly stated in the chord name. The reason we name chords maj7ths and such is to determine certain extension properteies. I.E. a flat, or regular 7th, a flat or regular third, etc.

Originally Posted by: Zamboni
Edit: I see what you're referring to, your previous post. Most chords DO have a fifth in it, that doesn't mean that it has to be explicitly stated in the chord name. The reason we name chords maj7ths and such is to determine certain extension properteies. I.E. a flat, or regular 7th, a flat or regular third, etc.

exactly, but for some reason i guess he wanted the fifth in the chord name.

Originally Posted by: FireAndIce24exactly, but for some reason i guess he wanted the fifth in the chord name.

yeah, it doesn't work that way.