I told you guys I'd do something related.

I was flipping through the Real Book (something everyone should own) and managed to land on this gem:

Sarah Vaughan and her band are killing it on this record, and Detour Ahead is a great jazz ballad by itself. It's even better for two reasons:

1. It has EVERY type of dominant chord we've been discussing recently

2. It was written by a guitar player. Herb Ellis to be precise, who if you don't know, you need to go check out.

So, without further delay, I'm going to run us through a quick and dirty analysis here and shed some light on the harmonic concepts, and then open the floor for questioning (read: How the F@%! do we sound good over this many chords).

Lead sheet is attached; had to use a pic from my phone. Ignore my cables and strap (the tools of genius ) lying around.


Okay I'm gonna take this one line at a time. Let's look at line 1. We are in C major.


Cmaj7 - F#7b9 | B7#5* | Fmaj7 Em7 Am7 | D7 Dm7 G7 | ---> | Imaj7 (V7/B, no real function) | V7/III | IVmaj7 IIIm7 Vim7 | V7/V | IIm7 V7 |

*Like all Dom7#5 chords, 90% of them are actually Dom7b13. For many reasons, the chiefest being calling the note G in the key of C... F## is stupid and counterproductive. I'm going to do a thread on this one day I promise.

Other than that, this is easier than it looks.

Cmaj7 is the Imaj7 chord. Duh

F#7b9 is the V7 of some type of B chord. Looking ahead, we stuck B7's V (F#7b9) in front of it to smooth out the transition, but the F#7 chord has no function beyond getting us to B7 in a cool way. I wouldn't really give it a Roman Numeral (because calling it V7/V7/III is moronic ), just know that it's the V7 of a B.

B7b13 is V7/III, a secondary dominant. B7 resolves to Em7. Which it does.

But not before we embellish it with Fmaj7, IVmaj7. Think of it (for you counterpoint nerds) as a big suspension.

Then we cut right over to the VI, Am7.

D7 is V7/V, another secondary dominant. Note the up by 4th root motion from Am7 to D7. That's very popular in jazz, but I wouldn't call this a II-V in G because these chords both function in C, and the movement is across the bar line. That's a big deal, but beyond the scope of this thread.

As expected, V7/V resolves to V7 (G7) but not before we stick a IIm7 (Dm7) in front of it for a little extra movement. You can stick a related IIm7 in front of any V7 chord; this is called Interpolation.

Again, note, just like the B7 before it, these delayed resolutions from secondary dominants still count and sound as such.


|Gm7 C7| Fmaj7 Bb7| Cmaj7 Am7 | Ab7#11 Dm7 G7| ---> | (Interpolated II) V7/IV | IVmaj7 bVII7 | Imaj7 VIm7 | SubV7/V IIm7 V7 |

2nd Ending: |F#m7b5 B7| ---> | IIm7b5 V7|(In E minor)

Slightly more nebulous, but straightforward.

Gm7 is an interpolated IIm7 of the next chord. The reason the previous Interpolated II (Dm7) gets a roman numeral and not this one is because Gm7 is not a functional chord in C major.

C7 is another secondary dominant, V7/IV. This one resolves apporpriately, with no delayed resolution this time.

Fmaj7 is IVmaj7 again. See, told you

Bb7 is a backdoor dominant. This is a dominant chord that resolves up by whole step to its target. This still has function, so we can name it bVII7.

Cmaj7 and Am7 are Imaj7 and Vim7 again, and Dm7 and G7 are also IIm7 and V7 again. Which leaves us the Ab7.

Ab7 is the SubV7/V. This is a tritone substitution of D7, the V7/V. These two chords share the same tritone (F#/Gb and C) and are a tritone apart, so we can substitute them for each other, the tritone in the Dom7 chord still resolves to its target, but now the root moves down by 1/2 step in stead of up a 4th. This is the other type of dominant motion.

Did that not make total sense? Let's spell it:

D7 = D F# A C -> note the tritone between 3 and b7, F# and C
Ab7 = Ab C Eb Gb -> note the tritone between 3 and b7 C and Gb(F#)

When D7(V7/V) resolves to G, the tritone resolves appropriately. F# goes up to G, and C goes down to B.

When Ab7 resolves to Db (because Ab7 is V7 in Db), the same tritone resolves in the opposite direction, Gb goes down to F, C goes up to Db.

What if we decide to resolve Ab's tritone like D7's tritone, but keep the rest of the chord? Now instead of D7 to G, we get the ultra smooth Ab7 to G.

TLDR We can swap dominant chords a tritone apart so they resolve down by half step for some sophisticated stuff.

"BUT JET?" You cry. "The Ab7 goes to Dm7 not G7!"

No it goes to G7, Dm7 is again, an interpolated IIm7. Delayed. Resolution.

Only one thing left. The second ending. Super easy. F#m7b5 - B7 is a minor II - V (IIm7b5 V7) in E minor. We just changed keys.


These are almost the same so I'm doing em both. Remember, we're in E minor now.

|Em7| B7(alt) | Emaj7 | F#m7b5 B7 | ---> | Im7 | V7(alt) | Imaj7 | IIm7b5 V7|

| The same shit again | Db7#11 |----> | The same shit again | SubV7 in C MAJOR |

Nothing here is out of the ordinary, this is all just standard chord progression fanfare in E minor.

Except Emaj7. Nice deceptive resolution. I would'nt call this a key change, we're just hanging out on Emaj instead of Em for a bar.

The next line is the same shit again until we get to Db7. That's SubV7 in C. It's a tritone Sub for the V7 chord (G7) in C major, because we are headed back to our original key for the A section.

The A section is just the same stuff until the last 4 bars, which I've analyzed below.


|Cmaj7 E7#9 | Am7 Eb7 | D7 G7sus4 | C6 G7#5 | ---> | Imaj7 V7/VI | VIm7 SubV7/II | V7/V V7 | Imaj6 V7b13*|

Cmaj7 is Imaj7 again.

E7#9 is our last secondary dominant, V7/VI.

It resolves as it should to Am7, VIm7.

Now we get the Eb7. Notice how it resolves down a 1/2 step to D?. SubV7/II! It's another tritone sub, this time for the V7/II(A7)*.

Instead of resolving it to Dm7 (IIm7), we instead go to the OTHER D chord. D7, aka V7/V. That resolves to V7(G) and then to Imaj6 (C).

We do a quick turnaround with V7 (G7#5*) and start over. That's IT!

*Except this is G7b13 for the same damn reasons.


That's all I got people; I could write for hours on all the different ins and outs of this and where we can go and what we can do but It'd be too much. Let's discuss instead; I'm here to talk; especially about strategies for making robot guitar noises over this .
"There are two styles of music. Good music and bad music." -Duke Ellington

"If you really think about it, the guitar is a pointless instrument." - Robert Fripp
Double Post because I'm a spaz and hit the button twice.

Edit: I'm keeping it now Neo, I've grown attached to it.
"There are two styles of music. Good music and bad music." -Duke Ellington

"If you really think about it, the guitar is a pointless instrument." - Robert Fripp
I can't focus at all thanks to just waking up after a mostly sleepless night, but I'll check this out after the coffee kicks in and a warm shower. I didn't listen to the recording yet, but those chord changes could make a fun bassline....
Quote by Jet Penguin
Theory: Not rules, just tools.

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*note that by fan i mean that guy who wants his friends to know he knows this totally obscure hip band that only he knows about with 236 views on youtube. lookin' at Kev here
Jet..nice breakdown...for those new to jazz harmony..this could be a real eye opener..but the roman numerals are a very quick way to transpose a tune..as they are the SAME in every key..rather than alpha/numeric..which are DIFFERENT in every key..and fairly difficult to transpose and memorize in every key..

the first line I would break down just a bit different .. I first want to see the "logic" of a progression and its essence...so I see it as a IM7 iii7 vi7 ii7 V7 IM7,,a very standard progression,,with harmonic alterations..the F#7 B7 to FM7 I see as a backcycled (V of V) b5 substitution for C7 going into FMA which is a nice change and gives new life to the line..

my point is when doing analysis of progressions like this..seeing chord relationships in roman numerals shows the scale steps - and their relation to each other much easier than just using alpha numeric..after this process is used as a guide..moving to more complex progression becomes necessary to begin to see the logic of the progression...A tune like "good-bye pork pie hat" by Monk..will stop most players in their tracks trying to analyze the tune for the first time if they are not familiar with it..as it is often called a "blues" tune..yeah right..
play well

Last edited by wolflen at Oct 27, 2016,
^Agreed, for the most part.

I don't consider the B7 back cycled because that chord has function in the key. Usually back cycled or interpolated chords don't have any function, but we can easily give that B7 V7/III so it's more likely a secondary dominant than anything else.

I mean the result is the same, so it doesn't really matter. You're right, we could just go C C7 Fmaj7.
"There are two styles of music. Good music and bad music." -Duke Ellington

"If you really think about it, the guitar is a pointless instrument." - Robert Fripp
Nice song. The "backdoor dominant" Bb7 sounds like a bluesy substitution for a G7, reinforced by the G in the melody. I love the word "trouble" over that chord in the last verse. Very moody.
I think I followed that. Mostly. Well,I was ok up to the "Duh", bit, at least.

Thanks, though, I mean if I read it through a bunch more times (and actually have a guitar with me ) I think I can follow that ok.
I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.