In a previous lesson I did a minor conversion analysis of the jazz standard “Giant Steps” as an alternate approach to improving on the notoriously difficult tune. Usually, references to the minor conversion approach will direct you to guitarist Pat Martino, whose lesson materials will typically start with showing interesting relationships between diminished and dominant chords, shows a lot of triangle and star shaped drawings, and then starts demonstrating insanely fast chromatic lines to play.
(One might suspect things are being made intentionally difficult…)
I’ve seen this hit on in other places since, but the first simple and logical explanation of minor conversion that I saw was in a book I bought 25 years ago: Jazz Guitar Lines by Lucky Elden, which I’m happy to see is still in print. It also has several more chromatic Pat Martino inspired licks in it, many that I still use today (Much to the confused looks of the other electric blues players I’ve worked with… but that’s another story)
But here’s the breakdown: Use your ears, but just about any lick that sounds good in A minor (Q: What, CD…? A natural minor? A harmonic? Jazz minor? A: Generally… yes!) will sound good in C major (its relative major); it should also sound good for D dominant (this is a standard ii – V jazz improvisors trick. Long ii – V – I, you can do two short ones on the long ii – V and they work, or half a long idea over a short ii – V.) Finally it also works on the chords for a minor ii – V, down a minor third: F#min7b5 and the various flavors of B7 altered (b9,#9, etc.)
In other words: An A minor lick should work with all of these chords; Amin7, Cmaj7, D7, F#7b5, and B7alt.
Major ii -V, relative major, and minor ii – V down an minor third.
A good lick or motif can now be plugged in over a major, a minor, a dominant, a half diminished 7, or an altered dominant.
Let’s analyze a standard ii – V – I in C using this system. Dm7… start your lick in Dmin. G7… you can still continue in Dm. Cmaj7… shift to an Amin idea. Repeated frequently is let your ear be the guide. If it sounds good, it is. If it doesn’t I often find one note in the line or a different resolving note usually cleans up the idea… or I drop it.
Perhaps not surprisingly, some of the most interesting stuff using this approach is the chromatic zippy lines similar to… Pat Martino. But I have used this with arpeggios and pentatonic scales with interesting results.
Please forgive the dry, text only, example free entry. If I find a free moment and don’t get distracted, I’ll expand a bit in a second entry.