When to use D7th vs. 'Normal' 7th note?

[danonearth]

Ok, I am just learning this theory and need some help when most people would use the D7th note (as opposed to a ‘normal’ Maj7) as either note could sound fine to me sometimes…

Note: please excuse any little mistakes, but it is the overall pattern/idea I am looking at - as far as I can tell, the only time you would play a ‘normal’ Major 7th is on the 4th interval chord?

So, for example:

If I am playing in C Major…

root chord = C, E, G, B

2nd = D, F (minor 3rd), A, C (dominant 7th)

3rd = E, G (minor 3rd), B, D (dominant 7th)

4th = F, A, C, E

5th = G, B, D, F (dominant 7th)

6th = A, C (minor 3rd), E, G (dominant 7th)

7th = B, D (minor 3rd), F, A (dominant 7th)

[ambient]

If you're harmonising a scale, it goes major 7, minor 7, minor 7, major 7, dominant 7, minor 7, minor 7b5, then back to major 7 on the octave.

The only dominant 7 is on the fifth of the scale. The others are called minor 7s (except the 4th major 7).

[Steve Woodcock]

The correct name for the [i]interval[/i] you are referring to is a [b]minor seventh [/b]- 'dominant 7th' is the name given to the [u]chord[/u] built on the dominant degree of the scale (the fifth).


Therefore, in C major, you have the following seventh chords:

Cmaj7: C, E (M3), G (P5), B (M7)

Dmin7: D, F (m3), A (P5), C (m7)

Emin7: E, G (m3), B (P5), D (m7)

Fmaj7: F, A (M3), A (P5), G (M7)

G7: G, B (M3), D (P5), F (m7)

Amin7: A, C (m3), E (P5), G (m7)

Bø7: B, D (m3), F(º5), A (m7)


m3 = interval of a minor third
M3 = interval of a major third
º5 = interval of a diminished fifth
P5 = interval of a perfect fifth
m7 = interval of a minor seventh
M7 = interval of a major seventh

Have a look at this video:

[media]http://youtu.be/rY4rkG2pX1Q[/media]

Edited October 12, 2016 by Stickman

[JapanAxe]

The dominant 7th refers to the 7th chord built on the dominant scale degree, so in the key of C that would be G7. Things get a bit more complicated because the same chord can function as a 'secondary dominant' so for example the chord G7 may be used in the key of Eb to take you to the chord of Cm.

If you are going to play a 7th as part of an arpeggio or scale run, you need to think of the chord behind it and its function.

Much confusion arises because the term 'minor 7th' can refer to an interval (pitch distance between 2 notes) or to a chord (minor chord extended with a 7th).

I'm going to butt out here and suggest you find a good book about chords!

EDIT: What Stickman said while I was typing on my iPad!

Edited October 12, 2016 by JapanAxe

[danonearth]

[quote name='ambient' timestamp='1476310339' post='3153320']
If you're harmonising a scale, it goes major 7, minor 7, minor 7, major 7, dominant 7, minor 7, minor 7b5, then back to major 7 on the octave.

The only dominant 7 is on the fifth of the scale. The others are called minor 7s (except the 4th major 7).
[/quote]

Ah, yes... I forgot the b5 on the 7th

Ok, got it! I think I am confusing the difference between minor 7 and dominant 7 - my friend told me the dominant 7 was a b7 - but I am using it wrong in this sense... I understand now I should have used minor 7th (as you did!

Thanks!

[danonearth]

[quote name='Stickman' timestamp='1476310974' post='3153327']
The correct name for the [i]interval[/i] you are referring to is a [b]minor seventh [/b]- 'dominant 7th' is the name given to the [u]chord[/u] built on the dominant degree of the scale (the fifth).


Therefore, in C major, you have the following seventh chords:

Cmaj7: C, E (M3), G (P5), B (M7)

Dmin7: D, F (m3), A (P5), C (m7)

Emin7: E, G (m3), B (P5), D (m7)

Fmaj7: F, A (M3), A (P5), G (M7)

G7: G, B (M3), D (P5), F (m7)

Amin7: A, C (m3), E (P5), G (m7)

Bø7: B, D (m3), F(º5), A (m7)


m3 = interval of a minor third
M3 = interval of a major third
º5 = interval of a diminished fifth
P5 = interval of a perfect fifth
m7 = interval of a minor seventh
M7 = interval of a major seventh

Have a look at this video:

[media]http://youtu.be/rY4rkG2pX1Q[/media]
[/quote]

Thanks, Stickman

I just figured it out great video too! I find it hard to find good bass theory - most is guitar chord theory

Thanks again!

cheers,
Dan

Edited October 12, 2016 by danonearth

[ambient]

[quote name='danonearth' timestamp='1476311278' post='3153332']
Ah, yes... I forgot the b5 on the 7th

Ok, got it! I think I am confusing the difference between minor 7 and dominant 7 - my friend told me the dominant 7 was a b7 - but I am using it wrong in this sense... I understand now I should have used minor 7th (as you did!

Thanks!
[/quote]

The dominant 7 is a b7. It's maybe what's confusing you. The chord built on the 5th degree of the scale is called a dominant 7 chord. It has a major 3rd and a b7. If you play it as a 7 chord, it's called a dominant 7 chord, as a triad it'd be a major triad.

Edited October 12, 2016 by ambient

[Number6]

I'm lucky enough to not have a clue what anyone is talking about in this thread

[danonearth]

[quote name='ambient' timestamp='1476311448' post='3153334']
The dominant 7 is a b7. It's maybe what's confusing you. The chord built on the 5th degree of the scale is called a dominant 7 chord. It has a major 3rd and a b7. If you play it as a 7 chord, it's called a dominant 7 chord, as a triad it'd be a major triad.
[/quote]

Yes, I think I was 'thinking' the right thing, but using the wrong terminology... Thanks again for helping clarify it for me

cheers,
Dan

[danonearth]

[quote name='Number6' timestamp='1476311654' post='3153335']
I'm lucky enough to not have a clue what anyone is talking about in this thread
[/quote]

Lol! I wish I was the same... I have found the more you learn about theory, the more you need to know - it just never stops! lol

cheers,
Dan

Edited October 12, 2016 by danonearth

[ahpook]

[quote name='Number6' timestamp='1476311654' post='3153335']
I'm lucky enough to not have a clue what anyone is talking about in this thread
[/quote]

I think I do, but I'm just going to sit quietly in case anyone asks me anything....

[Nicko]

[quote name='ahpook' timestamp='1476311850' post='3153339']
I think I do, but I'm just going to sit quietly in case anyone asks me anything....
[/quote]

Its not clear whether the OP is referring to - i think it means when can I play a b7 instead of a maj7 and get away with it. The answer is whenever you like. Sometimes it will sound OK and sometimes it wont.

From a theory point of view if you create the secondary chords from the main song key it all shakes out (ie in Cmaj songs you only play the "white" notes on a keyborad) and any chord constructed from these is correct. But if you want to play a "black" note in a Cmaj progression you can use it as a passing note or as a dissonant harmony note.

But, as a bass player you have control, and if you choose to play a I,IV,V,b7 against the guitar playing I,IV, V chord progression you will in effect have turned their Cmaj song into a C Dorian modal song.

[ahpook]

[quote name='Nicko' timestamp='1476351245' post='3153477']
I think it means when can I play a b7 instead of a maj7 and get away with it. The answer is whenever you like. Sometimes it will sound OK and sometimes it wont.
[/quote]

Yep, that's my general understanding of it. Thanks

[paul_c2]

[quote name='danonearth' timestamp='1476309716' post='3153315']
If I am playing in C Major…
[/quote]

Firstly, there is no right or wrong. But there is nothing stopping you from playing a "wrong" note, or to put it another way, a note not in the diatonic scale. Certain "wrong" notes sound okay, and certain ones sound wrong!

[quote name='ambient' timestamp='1476310339' post='3153320']
If you're harmonising a scale
[/quote]

As above, really. Of course, sometimes it is good to stick to the diatonic scale.

[quote name='Nicko' timestamp='1476351245' post='3153477']
But if you want to play a "black" note in a Cmaj progression you can use it as a passing note or as a dissonant harmony note.

[/quote]

Exactly!


Basically, yes you're in a major scale, but don't forget that what [b]defines[/b] a scale as being major, is whether the 3rd is major (ie not minor, not Eb in the scale of C). So, Bb can be present, the scale is still major, but that Bb can be used to make a C7 chord. In fact since it is a tone away from C, instead of a semitone, it can sound quite pleasant compared to a dissonant Cmaj7 chord, and/or B natural. Sometimes the dissonance can be good though, for example it will create tension which can then be resolved to reinforce a cadence, etc etc For those who know their modes, effectively you can use the mixolydian mode instead of the ionian mode.

This is what a popular guitar online lesson provider says about 7ths:

[quote][b]7th[/b]
Adding in the 7th note of the scale ( B natural is pretty nice sounding, and this is the note that will make the chord Cmaj7 - if you were to play a b7 (Bb) it would then make the overall sounds a dominant chord! PLay and listen and you'll hear that it pulls to the root, it's not 'stable' and wants to resolve - meaning it created tension which needs to be released! The major 7th note adds some jazz flavour, where the b7 tends to sound kinda bluesey.[/quote]

From: [url="http://www.justinguitar.com/en/SC-160-ChordScalesRelationships.php"]http://www.justingui...lationships.php[/url]

Edited October 13, 2016 by paul_c2

[paul_c2]

Basically, another way of saying the above is to remember: don't look at theory as rigid walls that you must stay within. But remember where music theory originated from: people were creating music before understanding music theory. Through trial and error, they created music which sounded "nice". Later, analysts analysed this and created rules, which formed the science of music theory. And potential composers were taught these rules, since observing them provided a shortcut to creating music that sounded "nice".

Yes its definitely worth learning some music theory, to 1) save time and 2) give a greater understanding of what's going on, but don't worry too much, if you didn't then you will find out stuff through your own trial and error and that "stuff" is all good knowledge!!

[BigRedX]

You use whichever note sounds the best to you.

[Guest MoJo]

[quote name='Number6' timestamp='1476311654' post='3153335']
I'm lucky enough to not have a clue what anyone is talking about in this thread
[/quote]

You and me both

[ivansc]

Just for grins, next time you are playing Yet Another 12 Bar in A, instead of starting the run over the V chord on E, start it on B.
The seven I would usually only employ as a passing note in most cases, btw. either way you are going to wind up having to resolve it to the next natural anyway.