Beginner theory Finding the chords for a 12 bar blues

[cappers]

I would be grateful for some advice on determining the chords in a tune when they aren't given.

I am trying to solo a 12 bar blues over Green Onions (arranged by Terry Pack?). The key for tenor is noted as Dmaj and the music sheet states "Solos in Gminor blues"

I was told this was a mistake and solos should be in Aminor not Gminor. It was suggested I use Amin, with a couple of Dmin and Emin, all blues scales.

Amin blue ACDEbEG
Dmin blue DFGAbAC
Emin blue EGABbBD

The general format for a 12-BB is
I / I / I / I /
IV / IV/ I / I /
V7/ V7/ I / I /

So that suggests to me
A-/A-/A-/A-/
D-/D-/A-/A-/
E-/E-/A-/A-/

But looking at the the backing track I can't determine from the notes which chord is which. To me it looks more like 1/1/1/1, 4/1/1/1, 5/4/1/1?

It looks like
A-/A-/A-/A-/
D-/A-/A-/A-/
E-/D-/A-/A-/

Am I yet again totally confused and barking up the wrong tree? I understand how chords are constructed but find it difficult to determine what chord is played from the notes given.

Apologies for a long post; I hope I have made myself clear.

 

[lydian]

So I managed a long professional career with having no idea what it means if I saw Cj or Cd

The j and d are keyboard shortcuts in BIAB, not actual chord symbols. I don't see the relevance of it or the guitar tabs, but nice tip for BIAB users or beginner guitarists I guess. Maybe put X's on the muted strings for clarity. Otherwise that G7 becomes a G13 which is probably too jazzy or funky for most.

 

[cappers]

Hope that helps rather than confuses the issue.

Thank you. No confusion, it's beginning to sink in. Grateful for the help.

 

[JSL]

Thank you. No confusion, it's beginning to sink in. Grateful for the help.

I'm glad it made sense to you. A far better way to demonstrate voice-leading would be giving an example with a musical phrase, leading to, and through, the stepwise move from one chord to the next. You can do it in a very basic way with an ascending C7 arpeggio to descending F7 arpeggio, voice leading from Bb to A:

C E G Bb A C Eb F

I also like using chromatic approach notes leading into a chord tone, usually the 3rd. For ex, G# to A on an F7 chord. But that's a bit different idea. I'll resist mentioning enclosures.

 

[JSL]

Just checking because it looks like bars 52 & 56 are the same making the second 4 bars D-/A-/A-/A-

My question was the chord progressions from the notes in this arrangement. I've checked the two other tenor parts, and bars 52 & 56 are the same suggesting IV-I-I-I rather than IV-IV-I-I.

I went back and read the first page of this thread and while your question here was addressed by pointing out you can play the blues scale over the entire form, I didn't see anyone address the exact question you are posing in the quotes above. So, just in case it slipped by, those two phrases in the box you put in red are standard blues scale phrases, one played over the Imin chord and the other over the IVmin chord. So, bar 56 (bar 6 in the 12-bar form) is still the IV chord, not the I. That blues scale lick can be played over both those chords. So, it's IV-IV-I-I (not IV-I-I-I).

Apologies if this has already been clarified for you, but I decided to point it out just in case.

 

[cappers]

@JSL Thank you. Indeed a IV-IV-I-I
I sorted that out a while ago now but thanks for reinforcing it.
It's obvious now and rereading the posts I wonder how I was so dim 😳
GO is the band's set finale so I'm getting some experience developing 12BB solos over it.
Blues scales are the novice's friend

 

[JSL]

@JSL Thank you. Indeed a IV-IV-I-I
I sorted that out a while ago now but thanks for reinforcing it.
It's obvious now and rereading the posts I wonder how I was so dim 😳
GO is the band's set finale so I'm getting some experience developing 12BB solos over it.
Blues scales are the novice's friend

You weren't being dim at all. It's totally understandable for some of this to be a bit confusing at first, especially when it comes to the blues. And yeah, the blues scales are everyone's friend, not just the novices. Listen to the jazz greats playing the blues and you'll hear plenty of blues scale phrases. It's how those notes are used that makes all the difference.

 

[Colin the Bear]

It's very strange how the brain can't believe how it didn't used to understand before the penny dropped and the mists cleared.

Once you get it, it becomes obvious.
Sometimes going to sleep, struggling with a problem, it's a complete mystery how the answer appears in the morning.

I'm sure that all this puzzling and questioning keeps the brain creating new cells and functioning healthily. Fingers crossed. 🤞