How to pick chords for a melody?

[JonR]

Very concise and detailed reflections, thanks.

To keep the copy pasting of quotes down I'll respond the ones that matter the most.
(the rest you can more or less assume that i agree with)

Ditto...

I don't mean G melodic minor as tonality, but as a common harmonic element both in D major and D minor, and a good way to pivote(?) between major and minor, and a good way to prepare A7sus(b9)

Still don't quite follow that..

The b13 needn't be mentioned in the chord symbol i agree. It is present in the melody,

Except it isnt. No F natural in that bar.

No ofcourse, Bm11 is not from G melodic, minor but from B minor (d major), and i see it as a modulation to Bm , (parralel key).

It is a good transition chord preparing for D minor
(G minor melodic is a common basis for both , A7susb9 and F#7alt)

Ah, gotcha! The F#7 bar has a C# though... not quite G melodic minor... (trivial point though )

Actually I totally agree with that, (Although A whole tone ...with B in the bass? ).
I think the best option is to simply write : B wholetone

Agreed. B in the bass was my initial choice, simply because it ends up in E major.

[vhollund]

It is true that you just recently came up with the B in that context , I just tried to roll with it even if not finding any logic really, in the placement of the musical idea/melody
The chords i filled inn for the following bars , doesn't go back to E major though.
So if it depends on that, i guess it would depend on the version/ harmonic interpretation of the following melody.

If I was you momotor i'd put a little more work into that melody before saying "done".

[JonR]

It is true that you just recently came up with the B in that context

If we're splitting hairs, I didn't actually get that far in the tune in my first post. When I did (in post #9), I mentioned the B wholetone idea - so it was my "initial choice" when I first talked about that section.

, I just tried to roll with it even if not finding any logic really, in the placement of the musical idea/melody
The chords i filled inn for the following bars , doesn't go back to E major though.

That's true. I recognised he was merely "in a kind of E major ballpark", but you're right that section doesn't resolve into E. Into A if anything.

If I was you momotor i'd put a little more work into that melody before saying "done".

Agreed!

[JonR]

Unfortunately those were old tunes from my elementary school days years ago and I don't have the sheet music anymore. I just wrote it from memory and made some changes for "jazziness"

Unfortunately, it does kind of sound like that. It lacks coherence. There's too much going on, and it doesn't really hang together as one piece.
That's why I had a struggle coming up with satisfactory chords. The melody doesn't seem to know where it's going.
Try the singing test: can you sing this tune (accurately) all the way through? Or are there parts which are very hard to wrap your voice around, to get it in tune? All good melodies are singable (though you will often have to change the key to fit your vocal range).
To be singable they don't have to be simple, but they do normally have to retain a sense of key centre, or have some alternative logic.Parts of the tune work well in this respect, but others seem to have one or two odd note choices. The phrase shapes sound like poorly remembered ones: they usually make good rhythmic sense, but often poor pitch sense. That's why I say it sounds very much like you wrote it from old tunes from memory - and/or maybe your sense of "jazziness" is not quite trained enough.

Ie, I agree with vaughn that a little more work on the melody would be good. Maybe cut whole parts out - be ruthless! (or turn it into two or three separate pieces.) Most great jazz standards only have two different sections, A and B (in AABA format), each only 8 bars long. As a harmonisation project, you're giving yourself much too much to handle here.

[christianm77]

My advice would be this structure:

Harmonise at first very simply. Let's take as an example, Happy Birthday. The song can be harmonised with just three major chords, the three that most guitar players will be familiar with. Let's take the key of C major to make it easier. I call this the 'folk stage'
We have:

C | % | G7 | % |
% | % | C | %|
C | % | F | % |
C | G7 | C | (G7) |

Now, this isn't very jazz. The next step is to use the 'trad stage' as I call it. Here are some classic trad moves to dress up three chord progression.

Here are some - we can use a C7 or a more colourful to dress up the move to from C to F, for example, and Fm6 or F#o7 can be used to dress up the move from C-F. In all these cases, test the chords with the melody to avoid clashes.

Furthermore, being careful that the chords don't clash with the melody, we can introduce I-vi-II-V turnarounds. We can use two of these - C Am D7 G7 - in the last two bars. We have this New Orleansy progression.

C | % | G7 | % |
% | % | C | % |
C | E7 | F | F#o7 |
C Am | D7 G7 | C Am | D7 G7 |

OK, now we are going to apply the 'bop stage' - here we can incorporate more ii-V and ii-V-I progressions. One nice substitute is to replace the F#o7 - C move with F#m7b5 A7 Em - as Em can be used to sub for C.

Well add a ii in before E7 - Bm7b5 E7, Groovin' High style.

We can also use a ii-V for the extended G7 chord - in fact a little Funny Valentine walk down the Dm7 chord might be fun as well. We can set it up with an A7 chord.

Needless to say, feel free to extend these chords as you wish.

I'm going to pop in a Tadd Dameron turnaround at the end. This classic progression C-Eb-Ab-Db7 is rather chromatic, so I'm putting in the last two bars where the melody won't clash.

BOOM!
C | A7 | Dm Dm/C# | Dm/C Dm/B |
Dm | G7 | C A7 | Dm G7 |
C | Bm7b5 E7 | F | F#m7b5 B7 |
Em Am | D7 G7 | C Eb | Ab Db |

Now apply any more substitutes you like! These are not the only options in each case. Gm7 C7 might be a better choice than Bm7b5 E7 for example. I've used a lot of changes here - a simple approach might be more to your taste. Just because you can do something doesn't mean you should.

Finally, jazz is not the style of harmony so much as the rhythm and the phrasing.