#1
I'm a bit confused about dominant 7 triads. Are they the same as major triads? Can i figure this out easier through modes?
Last edited by play guitar 25 at Jan 22, 2009,
#2
Modes are not the answer to your problems. Seriously.

A dom7 chord has intervals of 1 3 5 b7. They aren't triads, they're 7th chords. In major harmony, they are built off of the fifth scale degree (or the dominant). So in the key of C major (CDEFGAB), the dom7 chord is G7.
Quote by dudetheman
So what? I wasted like 5 minutes watching DaddyTwoFoot's avatar.


Metalheads are the worst thing that ever happened to metal.
#3
Quote by DaddyTwoFoot
Modes are not the answer to your problems. Seriously.

A dom7 chord has intervals of 1 3 5 b7. They aren't triads, they're 7th chords. In major harmony, they are built off of the fifth scale degree (or the dominant). So in the key of C major (CDEFGAB), the dom7 chord is G7.


Perhaps i should have been more clear. You see, my problem is that im trying to figure out what type of triad to play over a dominant 7 chord. I know that a dominant 7 chord is 1 3 5 b7, but a triad is 3 notes, so which 3 of those 4 notes do i play?
#4
Modes won't really help you with understanding chord construction.

Dominant 7th chords are not triads.

Triads are three notes that are each a third apart.

Seventh chords add another major third on top.

If you look at the Major Scale 1 2 3 4 5 6 7
You see how if you go up a third from 1 you get 3. Up a third from 3 you get 5. These three notes form a major triad 1 3 5. If you go up another third from 5 you get 7. This gives you a Major seventh chord.

If we take the two basic forms of third major and minor and stack them in as many combinations as we can to get three note chords we get 4 different triads.

Augmented triad = Major third plus Major third = root major third augmented fifth (1 3 #5)
Major triad = Major third plus minor third = root major third perfect fifth (1 3 5)
Minor triad = minor third plus Major third = root minor third perfect fifth (1 b3 5)
Diminished triad = minor third plus minor third = root minor third diminished fifth (1 b3 b5)

If you add to each of these another third either Major or minor you get all the different seventh chords.

In particular if we take a Major triad and add a major third on top of the fifth we get a Maj7 which is made up of a root Major 3rd Perfect 5th and Major 7th. (1 3 5 7)

If we take a Major triad and add a minor 3rd on top of the fifth it gives us a Dominant7 chord which is made up of a Root Major 3rd Perfect 5th and minor 7th. (1 3 5 b7)

In the major scale if you build a triad off the fifth degree it is made up of 5 7 9 if you build a triad off the same note it is made up of 5 7 9 11. Because of the interval structure of the Major scale the 7 is a major third above the 5, the 9 is a perfect fifth above the 5, and the 11 is a minor seventh above the 5. So the diatonic chord built off the fifth degree is made up of a Root a major third a perfect fifth and a minor 7th. This gives us a dom7th.

Not sure how much this will help. Just ask more questions if you don't get it.
Si
#5
Quote by play guitar 25
Perhaps i should have been more clear. You see, my problem is that im trying to figure out what type of triad to play over a dominant 7 chord. I know that a dominant 7 chord is 1 3 5 b7, but a triad is 3 notes, so which 3 of those 4 notes do i play?


I think if you want to play a dom7 as a triad, you would omit the fifth, as all it does is reinforce the tonic. So it would be 1 3 b7. You also keep the tritone, keeping the sound of a dominant chord.

6661Edit: F*ck. Or just do that. ^
#6
Quote by play guitar 25
Perhaps i should have been more clear. You see, my problem is that im trying to figure out what type of triad to play over a dominant 7 chord. I know that a dominant 7 chord is 1 3 5 b7, but a triad is 3 notes, so which 3 of those 4 notes do i play?

I was typing in regards to your first post. Just saw this one.

You want the seventh quality and the major quality and the root.

If you can only play three notes and you want a dom7 play the 1 3 b7. Drop the fifth.

EDIT: This is still not a triad though.
EDIT 2:Man I'm too slow. Beaten to it again.
Si
Last edited by 20Tigers at Jan 22, 2009,
#7
If you want to play only three of the four notes, play the 1, 3, and b7. Those are the three that give the chord its sound. 5ths, being perfect intervals, tend to be so similar to the 1 that they aren't necessary to establish tonality unless you're working with diminished or augmented chords.
Quote by dudetheman
So what? I wasted like 5 minutes watching DaddyTwoFoot's avatar.


Metalheads are the worst thing that ever happened to metal.
#8
Quote by Austyn6661
I think if you want to play a dom7 as a triad, you would omit the fifth, as all it does is reinforce the tonic. So it would be 1 3 b7. You also keep the tritone, keeping the sound of a dominant chord.

6661Edit: F*ck. Or just do that. ^


That's not really a triad
#10
^no it is not a triad.

A triad a specific type of chord that has three notes stacked in thirds. They contain a root third and fifth of some type.

1 3 b7 is not a root third and fifth it is not three notes stacked in thirds and therefore is NOT a triad.

1 3 5 b7 is a particular type of chord - a seventh chord (a different type of chord than a triad). 1 3b7 is a derivation of a seventh chord it would be more appropriate to call it a seventh chord.

There's two parts to defining a chord as a triad - 3 notes and stacked in thirds. Thus a sus chord is also not a triad even though it is three notes.

Just trying to clear that up.
Si
Last edited by 20Tigers at Jan 23, 2009,
#11
Quote by 20Tigers
^no it is not a triad.

A triad a specific type of chord that has three notes stacked in thirds. They contain a root third and fifth of some type.

1 3 b7 is not a root third and fifth it is not three notes stacked in thirds and therefore is NOT a triad.

1 3 5 b7 is a particular type of chord - a seventh chord (a different type of chord than a triad). 1 3b7 is a derivation of a seventh chord it would be more appropriate to call it a seventh chord.

There's two parts to defining a chord as a triad - 3 notes and stacked in thirds. Thus a sus chord is also not a triad even though it is three notes.

Just trying to clear that up.


Yeah, the name for a chord that is a collection of three notes is a "trichord."

And play guitar 25, that's non-tertian.
Quote by dudetheman
So what? I wasted like 5 minutes watching DaddyTwoFoot's avatar.


Metalheads are the worst thing that ever happened to metal.
#12
Quote by DaddyTwoFoot
And play guitar 25, that's non-tertian.

I was gonna say that too but you got to admit non-turtial puts a smile on the face.

Si