Strategies to transpose are:
(1) Just sing the melody in different key and let the ear and finger
find the right chord and voicing.
(2) Decide how many chromatic notes up and mathematically calculate
next chord while playing
(3) writing down on paper the transposed chord and just play it.
(pre-calculating)
(4) using transpose function of sequencer or notation software.
(auto calculating)
:)
The laziest way is easiest but you learn the least. I should be capable
of doing (1) but it is difficult tune for that, and to do the (2) is
more confusing...
So my strategy was:
(5) analyze the skeleton structure of the tune and transpose the
skeleton on fly.
Here is GiantSteps change:
| BM D7| GM Bb7 | EbM | Am D7 | GM Bb7| EbM F#7 | BM | Fm Bb7 |
| EbM | Am D7 | GM | C#m F#7 | BM | Fm Bb7 | EbM | C#m F#7 |
It's made of V-I and ii-V-I sequence of three tonality.
When extracted only I chord, (tonal center) it is
| BM (V)| GM (V) | EbM | (ii V) | GM (V)| EbM (V) | BM | (ii V) |
| EbM | (ii V) | GM | (ii V) | BM | (ii V) | EbM | (ii V) |
Here we got
B - G - Eb, G - Eb - B, Eb - G - B -Eb
or gradually:
|-------------------------------------------------------------------
| E (down 3rd) ||
| B (Down 3rd) B (up 3rd) || B
| G (Down 3rd) G (Down 3rd) G (up 3rd) ||
| Eb (Up 3rd) Eb (Down 3rd) Eb (Up 3rd) ||
| Bb (Up 3rd) ||
|-------------------------------------------------------------------
So only thing I should remember is this sequence of
Down-Down-Up Down-Down-Up, Up-Up-Up-Up Down.
Easiest key to transpose is major 3rd up in G or major 3rd down in Bb.
they are almost identical.
And now I'm working on key in F...
If ears know exactly how it should sound, it's easier for fingers to
remember it. When I make many mistakes at same place, I should doubt
the flow of voicing is not right. It's time to revise the voicing.
After fixed it and found better sound, how complicated it is, fingers
move naturally to make this sound. Music is a art of ears.
==========================================================
Now about consideration to make phrase on this change.
Strategy (1): because everything is made on V-I and ii-V-I, use
licks of V-I and ii-V-I progression and try to forget the former
tonality immediately as tonal center moves.
Strategy (2): make phrase _on_ the tonal change.
Compare the diatonic tones on transition to major 3rd down:
G: G A B C D E F#
Eb: G Ab Bb C D Eb F four notes are flatted
Compare the diatonic tones on transition to major 3rd Up:
Eb: G Ab Bb C D Eb F
G: G A B C D E F# four notes are sharpened
So just being conscious of these four notes on voice leading,
you can ride the horizontal melodies.
(Indeed Coltrane made the melody of the tune this way, didn't he?)
=============================================================
More in detail, this tune has three transitive situation
(1) Major 3rd Down and go to V7 of new I.
(2) Major 3rd Down and go to ii of new I.
(3) major 3rd Up and go to ii of new I.
Mark where these change occur and study chord notes (and upper
chord notes) of transition, then you are prepared to phrase anywhere
of the tune.
Good exercise is for example play one of four notes in my voicing
of previous post, play all in half note. (so you are playing counter
melody or inner voice of the theme). When you feel comfortable
to ride on the half note, then add ornament note (or grace note)
to each, from half or whole tone up or down, forming rhythmical
4 beat like phrase. You did it? then it's the time to improvise
freely. Congratulation.
=============================================================
As a beginner :), I'm still far from improvising such complicated
tune :(. My purpose is rather making song with tonal skeleton like
this, using different intervals.
Playing this GieantSteps slowly with steady 4 beat, I got feeling like
listening some Harbie Nichols tune. Or using minor progression or
resolution to Isus chord, etc, you can make many challenging changes
yourself.
Feedback appreciated.
muchan