Beginner impro Why are dominant 7th chords called dominant?

[cappers]

I am trying to get my head around chords!

I think I understand Major 7th construction: major chord arpeggio 1,3,5 + 7, whereas the Dominant 7th has a flattened 7th so 1,3,5 + 7b.

CMaj7: C E G B ->** EDom7: CDom7 or more correctly C7: C E G Bb (Thanks @PiccoloPirate)
DMaj7: D F# A C# -> DDom7: D F# A C
EMaj7: E G# B D# -> EDom7 E G# B D
etc

My question is why is it named 'dominant'? I believe the 7th is a 'leading tone', so is the 'dominance' the fact that it needs to resolve down to sound correct? Also can it resolve up instead?

Thank you.

** edited to correct typo

 

[LostCircuits]

@Dibbs

Apologies for my slowness but would you explain this more.

"the dominant seventh is the seventh chord formed on the 5th (dominant) of the scale".

What I think it means is:

For C Maj the 5th (dominant) note of the scale is G.
The 7th chord of G Maj is G B D F# (Mixolydian mode?) and the Dom7th (G7) is G B D F.

"It's also good to point out that it contains all the scale notes NOT in the tonic triad".

The tonic triad of C Maj is C E G so with the notes of G7 we get G B C D E F, so as @Nick Wyver wrote, where's the A?

For my old brain, thinking M7 is Maj7 with the 7th dropped a semitone is easier to grasp.

I tried to read this aloud to myself in order to memorize it or understand it and ended up - again with Danny Kaye and the vessel with the pestle

View: https://www.youtube.com/watch?v=TJ9f2rnjB84

 

[PiccoloPirate]

The triad chord built on the seventh note, of a Cmajor scale is, BDF.
Often that triad is noted as Bdim or B°

These are the triads.
Major
Minor
Diminished
Augmented

 

[BigMartin]

The triad chord built on the seventh note, of a Cmajor scale is, BDF.
B Half-diminished

Strictly, that’s diminished triad. It only becomes half-diminished when you chuck in a b7 (A in this case), whereas a (fully) diminished 7th chord has a doubly flattened 7th (Ab).

 

[PiccoloPirate]

In the key of C major,
CMaj7 CEGB
CM7 CEGB
C∆7 CEGB
C7 CEGBb

 

[PiccoloPirate]

Strictly, that’s diminished triad. It only becomes half-diminished when you chuck in a b7 (A in this case), whereas a (fully) diminished 7th chord has a doubly flattened 7th (Ab).

Late night error,
Thx

 

[Pete Effamy]

To be picky, I'd call a chord built on the 7th a vii chord (with no "th").

That’s absolutely correct, not picky. The seventh chord in a key.

 

[Pete Effamy]

In the key of C major,
CMaj7 CEGB
CM7 CEGB
C∆7 CEGB
C7 CEGBb

You forgot Cma7. And the triangle can stand alone too. Even though all these are all recognised symbols imo some have virtually been confined to history. The capital M is from the ‘30’s or so and as Pete says, can easily be mistaken for a lower case m hence a minor - very much so in the old fake books with handwritten chords, some are very ambiguous.

The triangle - wasn’t that an Aebersold creation? I favour it, personally, as it’s far quicker to write, especially without the redundant 7. Numbers only needed if a 9 for major 9 (can’t type a triangle here).

Same with minor symbols. An m is by far the quickest and easiest.

Cm7.

Cmi7 or Cmin7 just aren’t necessary. In fact, the “skinny “ symbols really come into their own when you have busy parts and not much room to fit chord symbols in, especially if lots of harmony movement. Some score writing software gives comparatively huge chord symbols.

Cm7b5.

The long-hand style is still prevalent, the (Aebersold again?) circle with a cross through it as you wrote in an earlier post doesn’t seem to have been adopted by many at all. Same with the o for diminished.

Cdim7
Strangely never abbreviated to a Cdi7. Arguably, the 7 isn’t required in the symbol.

Caug - augmented triad. This really is a triad as like the diminished chord it’s symmetrical, but in this case each interval is a major 3rd. So in the case of a C augmented triad you get: C, E, G# and then C again.

Caug7
C+
C+7

 

[Pete Thomas]

Somewhere on this site is an arpeggio exercise for those scales.

 

[cappers]

OK, my simple question on why the dominant 7 is so called has turned into a marathon.
I am grateful for all the responses and advice but I am still puzzled over some of it! Specifically this comment from @Colin the Bear

"A penny dropped for me when I learned that Cmaj7 is in key of C but C7 is in key of F."

C7 is CEGBb, and Bb is in the scale of F which I can follow...
......but Bb is the 4th degree of F (F G A Bb C D E F), the 5th is C???

"the dominant seventh is the seventh chord formed on the 5th (dominant) of the scale".

I promise to go away and practice but I need to get this sorted in my head.
Thank you for your collective patience!

 

[LostCircuits]

You forgot Cma7. And the triangle can stand alone too. Even though all these are all recognised symbols imo some have virtually been confined to history. The capital M is from the ‘30’s or so and as Pete says, can easily be mistaken for a lower case m hence a minor - very much so in the old fake books with handwritten chords, some are very ambiguous.

The triangle - wasn’t that an Aebersold creation? I favour it, personally, as it’s far quicker to write, especially without the redundant 7. Numbers only needed if a 9 for major 9 (can’t type a triangle here).

Same with minor symbols. An m is by far the quickest and easiest.

Cm7.

Cmi7 or Cmin7 just aren’t necessary. In fact, the “skinny “ symbols really come into their own when you have busy parts and not much room to fit chord symbols in, especially if lots of harmony movement. Some score writing software gives comparatively huge chord symbols.

Cm7b5.

The long-hand style is still prevalent, the (Aebersold again?) circle with a cross through it as you wrote in an earlier post doesn’t seem to have been adopted by many at all. Same with the o for diminished.

Cdim7
Strangely never abbreviated to a Cdi7. Arguably, the 7 isn’t required in the symbol.

Caug - augmented triad. This really is a triad as like the diminished chord it’s symmetrical, but in this case each interval is a major 3rd. So in the case of a C augmented triad you get: C, E, G# and then C again.

Caug7
C+
C+7

I actually learned (in highschool ) to write major chords as capital letters and minor as lower case. So it was C and a, F and d etc.

 

[Pete Effamy]

I actually learned (in highschool ) to write major chords as capital letters and minor as lower case. So it was C and a, F and d etc.

That's interesting. I've never seen that. I think Aebersold was making a bid to standardise chord symbols worldwide. With the relaxation and shorthand of written music and symbols (brought about by having to get arrangements out faster? - although professional copyists were phenomenally quick back in the day) I guess we just get used to the style of which bands we play in and their charts. So long as it works...

 

[mizmar]

......but Bb is the 4th degree of F (F G A Bb C D E F), the 5th is C???

I think, as I understand/see it, is that some of the conversation is actually about harmonic motion.

So like how cadences work or how to follow chords through a tune or how to change key; in a satisfying way - often by modifying chords so that you can resolve somewhere else.
Although the modified and extended chords my just add pretty tones or produce tensions to be revolved in a satisfying way, they can also be used to move the tonic around...
... In the case above (maybe?) to move the tonic from C to F via C7 a modified tonic of C and a dominant of F so can resolve to the tonic of F suggesting a key change?

And in a twist if irony
this thread uses subject motion to resolve tensions in describing chords to resolve to a discussion of harmonic motion.

 

[mizmar]

That didn't help!
Sorry

I'm sure someone else can either explain it better or tell me I'm talking rubbish

 

[Pete Effamy]

OK, my simple question on why the dominant 7 is so called has turned into a marathon.
I am grateful for all the responses and advice but I am still puzzled over some of it! Specifically this comment from @Colin the Bear

"A penny dropped for me when I learned that Cmaj7 is in key of C but C7 is in key of F."

C7 is CEGBb, and Bb is in the scale of F which I can follow...
......but Bb is the 4th degree of F (F G A Bb C D E F), the 5th is C???

"the dominant seventh is the seventh chord formed on the 5th (dominant) of the scale".

I promise to go away and practice but I need to get this sorted in my head.
Thank you for your collective patience!

I come across as a crotchety old pedant, but we really have to watch how we formulate sentences in words, as they sometimes have a specific meaning in music, depending upon how you have written / said them.

"the dominant seventh is the seventh chord formed on the 5th (dominant) of the scale"

As has been pointed out, the above sentence is misleading, although a seasoned musician would know exactly what was meant by it. As it stands, "the seventh chord" really means a chord built upon the seventh degree of the scale - in C major, that is B, counting C as one:

C D E F G A B C

maj7 - Cmaj7 in this case - is most often used as the key-chord or root. Call it chord 1. That's why it belongs to C major.

C7 belongs to F major as it is the dominant 7th chord of F major (and minor).

Let this stuff absorb. Some of it will go in really easily but some of it will take some time, especially without someone sat at a piano with you and showing you how / why things work and what they sound like.

 

[Pete Effamy]

In the case above (maybe?) to move the tonic from C to F via C7 a modified tonic of C and a dominant of F so can resolve to the tonic of F suggesting a key change?

It provides a smooth transition (one of) through the pull to resolve of the tritone E and Bb as outlined by someone earlier - E to resolve upwards to F and the Bb downwards to A etc - a tritone is happy to resolve inwards.

C7 to F is merely harmonic movement (and yes also a Perfect cadence - a whole new set of abstract words meaning nothing much outside music), a snap in time. It only becomes a new key if the following music has chords / notes which suggest F major moreover C major. F, is of course, chord iv of C major.

If the melody transitioned from having B naturals, and being quite "Rooty" around C tonality - lots of C's and E's etc to having more Bb's, F's and A's etc - more rooted in F, then maybe it has transposed. But Jazz and Blues music blurs this with much usage of "Blue" notes - so even 1 chords might be changed to be a dominant type - C7 - rather than a major "quality" - Cmaj7 - (terminology as used in some circles). A Bluesy / Jazzy melody might have Eb's and Bb's in abundance, maybe solely - but still be in the key of C major.

Talk of harmony can go to deep waters very quickly, so it's best not to introduce other ideas.

 

[mizmar]

It only becomes a new key if the following music has chords which suggest F major moreover C major. F, is of course, chord iv of C major.

Sure. I got carried away.
I was just thinking that some of the discussion was beyond how chords are constructed (named, notated) to how they function...

But, @cappers, early in my venture into music I quite quickly bought a cheap electronic piano to understand this stuff - and actually upgraded it even though I potter on it badly and rarely; it's easily the best tool for understanding this stuff.

 

[Pete Effamy]

Sure. I got carried away.
I was just thinking that some of the discussion was beyond how chords are constructed (named, notated) to how they function...

But, @cappers, early in my venture into music I quite quickly bought a cheap electronic piano to understand this stuff - and actually upgraded it even though I potter on it badly and rarely; it's easily the best tool for understanding this stuff.

I agree. It's great when you (finally) get Eureka moments..

 

[cappers]

I come across as a crotchety old pedant, but we really have to watch how we formulate sentences in words, as they sometimes have a specific meaning in music, depending upon how you have written / said them.........

Thanks @Pete Effamy You aren't being pedantic, proper terminology is important. Thank you for your help, sometimes I feel really out of my depth!

I do have a cheap electronic keyboard, an old Casio CTK-1200 and I am using it to try and understand (hear) all this. Hopefully I will get there in the end!

 

[Dr G]

My question is why is it named 'dominant'? I believe the 7th is a 'leading tone', so is the 'dominance' the fact that it needs to resolve down to sound correct? Also can it resolve up instead?

What’s in a name? Why is black? It’s a name. It’s meaning is arbitrary, yet now we try to make sense of it like Bob Dylan’s lyrics.

As to whether a note can resolve up or down, play it to see where your ear guides you today. The way you interpret the things you hear may change.

 

[cappers]

@Dr G A rose by any other name etc.....! I agree but since there are a lot of new words and concepts for me, I was interested in their derivation and meaning. I could have looked it up on Wikipedia but preferred to hear it from sax players/musicians on here. As you infer, it's not that important!

I have been trying out different notes and patterns on the keyboard, and yes resolving up just leaves the phrase hanging to my ears whereas down has a satisfying feel to it. Down by a semitone sounds better than a whole tone or more.