# where does the dominant IV7 (ie; F7 in the key of CMaj) come from?

So, I'm learning to get "outside" chords, by borrowing from parallel scales. Other chords are available by taking the secondary dominants of different degrees. For example, to get EMaj while in the key of CMaj, no other parallel minor or mode has EMaj, so it must be taken as the (V/vi or VI).

My issue now is finding how to properly get the dominant of the IV degree, for example in the key of CMaj, the chord of F7 (F dominant 7)

Diatonically, the IV chord is a Major 7th, not a dominant 7th.

I would say F7 is the V of Bbm or BbMajor, but in the key of CMaj, the degree rooted on B is B diminished, which does not have a scale of its own.

So, theory-wise, would F7 be "available" when considering as the "V/bVII"?

You would first need to look at the paralle minor, find the bVII degree & use its dominant?

For example, CMaj looks as c minor. the bVII degree of c minor is Bb. the V of bVII (Bb) is F7

• To be honest, the way you get to it is just by playing it, you don't need to justify it! However if you want some theory you could say its related to the back-door ii V I. In the key of C that's Fmin7, Bb7, Cmaj7. It's a commonly used chord sequence or reharmonisation with similarities to the ii V I (hence the name of course). In that sense the F7 would be behaving as the secondary dominant of the Bb7, and have a fair amount of drive to the C. Jun 23, 2022 at 22:51
• I dont think every chord has to be expressed as being part of some diatonic scale. Just look at the context - how is the chord being used? A IV7 chord can just be looked at as a IV chord with some "flavor". That is arguable how it gets used in blues/jazz Jun 24, 2022 at 18:11
• It comes from the blues and jazz. Many songs have Dominant 7 chords for flavor that we all heard for 100 years. They use instead of having their creativity dictated by music theory. Use your ears, if you like it then play it that way.
– r lo
Jun 24, 2022 at 20:04
• Let's see... 3 upvotes, 8 answers. Something is not right here. 3 people thought it was worth asking, 8 people thought it was worth answering. Jun 26, 2022 at 10:39

Long answer. I guessed and extrapolated what you might mean, so this could be off by a mile.

If by "F7 in the key of C major" you mean a style like blues where everything is a dominant-seventh chord, tones are bent, minor and major chords are fused etc., then I don't think you'll be able to fit everything into the functional harmony model. You may be able to identify something like tonic, subdominant and dominant - but even your tonic, when the harmony is at rest, is a dominant-seventh chord, and still nobody expects it to "resolve" anywhere.

If your song is like this

C7 C7 C7 C7 F7 F7 C7 C7 G7 G7 C7 G7

then I don't see any usefulness in thinking about borrowing, relative or parallel this and that, or if something is "from" Bb major. There is no expectation in my mind that the F7 chord would bring any hint of a possible modulation or anything. What comes to scale degrees, during the F7 chord, E is flat. During the C7 chord, B is flat.

Music is culture, and music theories are more or less systematic or formal, or at least established, ways of talking about things that are done or happen in music. Some theories i.e. ways of talking fit certain cultures well. Functional harmony, in the sense that you seem to try to apply it, is a good fit for talking, describing or reasoning about the music of "eighteenth- and nineteenth-century Western composers (what we call the 'common practice') ..."

http://openmusictheory.com/harmonicFunctions.html

... but it is not a universal law of nature or theory like quantum mechanics. Music is humanistic, culture, not natural science. In natural sciences, theories talk about nature. In humanistic sciences, theories talk about what people do. Music theories largely fall in the latter category. There are some simple physical phenomena like sound waves that music is built on, but harmonic styles build on learned expectations.

There is no single unified "theory of harmony" that would be useful for describing all harmonic styles in all cultures. Except maybe some meta-theory, which would be a theory about theories, i.e. talking about ways of talking about music.

So, depending on the style of the song you're describing, there are many ways to answer the question "where did the IV 7 chord come from". Maybe it came from blues? If you think of each harmonic style as a ball game, you need to know the rules of the game before you start saying that one of the players "is" a pitcher or goalkeeper or quarterback. Maybe there is no goalkeeper in this game at all, so chances are that whichever player you try to identify as the goalkeeper, is not one. Maybe in this ball game, not everything is aligned to some diatonic scale grid.

What comes to playing outside, a very important aspect is rhythm. If you play, say, pentatonic lines in a completely different key, your ear will start tracking the notes, trying to see a picture there, because the soloist is clearly telling a story - even though it doesn't align with the expectations given by the backing chords. And then you get an "outside" feeling. But if you don't play the lines very clearly and precisely, then the ear doesn't track the lines so well because the solo notes aren't clearly telling a story. The solo is mumbling something unclear. And then the outside feeling is lost, then you're just playing "wrong". So it's not about what notes you play, it's also about how you play them.

It's a chromatic chord. It comes from the blues. That is good and sufficient reason!

It COULD be V7 of ♭VII, but it almost certainly isn't doing that!

Yes, its notes occur in the parallel minor scale. So what? No-one imagines that a C7, F7, G7 blues sequence implies any sort of a modulation to C minor.

Just let F7 be a colourful ('chromatic') chord in C major.

• It's a colorful chord, if you expected something different. :) But if you expected blues, then it's the plain vanilla thing in that style, no particular color added. Could a maj7 chord be "chromatic" in blues - or just a breach of style... Jun 26, 2022 at 10:15

If you are looking for the source of the IV7 you only have to look at the parallel Dorian mode. That is where the IV7 chord exists in its natural habitat.

It is also a V/VII (from the parallel minor) like you said. It also is a subV/iii. It exists in blues as a replacement for the IV chord. A lot of the time it functions as a non-diatonic IV chord. It also exists as a non-functional chord in many progressions.

The bottom line is context. There is no blanket explanation. If there is a IV7 within a chord progression you have to see how it relates to the rest of the progression to see if there is a functional analysis for it. Not every chord will have an explanation in functional harmony. Sometimes the ones that defy traditional explanation just sound good to us.

• It bears adding that, starting from C major, one can borrow C-7 from the parallel minor. But C-7 is also ii/bVII (that is ii of B flat major), so moving through C-7 gives a nice path to F7 and then Bb: ii-V-I. Jun 23, 2022 at 23:21
• @Aaron One of the cool things about Dorian mode is the “Tonic ii-V” for lack of a better term, actually a i7-IV7. It’s a very widely used progression in pop music (George Benson’s vamp on “This Masguerade”, Grover Washington’s “Mr. Magic” et al) made possible by the M6 of the Dorian mode which gives us a IV7 chord instead of a iv7. Jun 24, 2022 at 2:05
• 'Sometimes the ones that defy traditional explanation just sound good to us.' This is the important takeaway here. You dont need to fit every chord into a box to make something sound good Jun 24, 2022 at 18:14

1.In a Blues the minor 7th (Eb) of F is a blue note (minor 3rd of the tonic). Usually it may resolve to the root note C (passing tone D).

1. If this Eb resolves to E we can analyse it as D# - deriving it from f a c d# = Italian 6th chord (borrowed from the relative key a-minor)

https://en.wikipedia.org/wiki/Augmented_sixth_chord

There's a daily barrage of questions just like this - or strongly relating to it. Glad you're getting into 'outside' chords, but trying to find their raison d'etre is somewhat unneccessary. However -

Borrowed is one main cause quoted. Go to the borrowed notes which constitute Cm, and all the notes you need are there. Go to C Dorian, all the notes are there too. As you rightly say, it could also be construed as being V/vii from key C minor - so all those have a close relationship with C!

I daresay we don't often question what makes dogs go 'woof' instead of 'meiow' - we've come to accept that it's just what happens. I wonder if we could soon come to accept that 'odd' chords can and do occur wherever - without any good reasoning - ..! I reckon the majority of jazz players are already at that wonderful place, which is maybe why their music often sounds quite fresh. Agreed, some of them have progressed far past that and left us all floundering. Or is that just the Emperor's New Clothes..?

Well, the question is how strict you want to take this. The big problem with embedding F7 into the context of C major is that F7 is inherently linked to C minor, as it features a prominent Eb, which is pretty much the most discriminating element between C major and C minor. Thus this goes into a slightly different direction than borrowing chords from parallel scales, which is borrowing chords from parallel scales of the same key in minor.

This is similar to taking mediants of the minor key, i.e. using Ab major or Eb major in C major.

So, I'm learning to get "outside" chords, by borrowing from parallel scales.

If you're deliberately borrowing chords, then `IV7` could be the subdomiant seventh chord in minor when the progression is using the raised sixth and seventh degrees. In other words `IV7 V7 i`. Notice that `IV7` isn't really functioning as a dominant seventh chord. In that case I like to say it is the sonority of a dominant seventh chord. It "sounds" like one, but doesn't function as one. An example is given here.

The other possibility is the dominant of the subtonic chord. In `C` major, as borrowed chords, Roman numerals would be `C: ... V7/♭VII bVII`, in jazz symbols ` ... F7 B♭`.

To make that really feel like borrowed harmony you want to continue with something that maintains `C` as the tonic. Otherwise it might simply sound like a modulation to `B♭`.

dominant of the IV degree, for example in the key of CMaj

Just a detail about that wording. "Dominant of" usually means "dominant of... some tonic." So, the dominant of the `IV` degree, in the key of `C` means that the `IV` degree is `F` and the dominant of `F` is `C`, or as a full dominant seventh chord `C7`.

The dominant rooted on (built on) `IV` in `C` would be `F` or `F7`.

For me it makes sense to think of the Gypsy scale when using this chord. This scale is like the harmonic minor but with a raised 4. In A minor this would be A B C D# E F G#

Since D# is the minor seventh in the F chord it actually fits in the scale.