improvisation
i'm not really a pianist but here's what i know
There are a few places you can go from the tonic of a major key. IV is obvious and flirty, vi is obvious and sad. V feels like a foregone conclusion, but is steady and reliable if you’re just sitting down and you want to warm up your improv muscles. You can go to the major II if you’re feeling the CeeLo Green “Fuck You” vibe. The minor iv is sexy and a little mysterious, like who is she? And then from there you can go to the major bVI, which is kind of like the top of the ivm7, and then maybe the bVII back to I, which is a little corny but has just enough novelty to stay intriguing, especially if you do it sparingly (which I don’t, because it’s just too fun).
OK, and now you have the flat 6, and kind of the flat 3, and the flat 7, so maybe you’re in the parallel minor and you can throw in a im7, which can come down a fifth to the IV7, then down again to the bVIImaj7, and at this point you’re not really in the same key you started in, so maybe you start thinking a whole step lower, and the flat 7 becomes the tonic.
You can play back and and forth between these keys, introducing the flat 7, 3, and 6 incrementally and feeling out what feels nice. If you want to start getting a little funky with it, maybe you can come back to the home key and play with a sharp 4, either in the major II or as the twinkling 7th of the Vmaj7. If you’re feeling adventurous, you could even get the sharp 1 in there on top of a IImaj7, and now that you have the sharp 1, you can fudge it into a flat 2, and then you can shoehorn in a tritone sub, which dovetails nicely with the diminished and minor iv.
What else. Oh, if you want something that always sounds nice, you can dance around the pentatonic scale on top of the tonic or the IV or V. If you ignore all the leading tones (the 4, the 7), you can get something that basically just feels atmospheric, sort of like candy-colored clouds, like the base chord but with a little more personality. You can build out a lovely extended open-voiced arpeggiated chord in this way, like if you’re on the tonic you can place the 1 in the bass, then the 5, and then the 3 a sixth above the 5, and then the 2 and 6 or the 6 and then the 2, and everything will glisten underneath your fingers and you will feel very good at what you do.
It’s easier to cluster notes closer together in upper octaves; a major second in the 2nd or 3rd octave will feel muddy and ill-considered, while it might feel sexy and clever in the 4th or 5th. Also, it’s very easy for me to just keep resolving downwards, so I end up in muddy terrain a lot—maybe experiment with hands moving in opposite directions, because contrary motion always brings the intrigue.
There are two things that happen when you’re improvising: you’re thinking a lot about rules, like how the 7 needs to come up to the 1 and the 4 needs to come down to the 3, and falling down a fifth is always safe, and moving half steps is a good way to bring extra-harmonic color to the parent key, and about the flavor of all the variations of the 7th chords, and when you want to use a 9, a flat 9, a 11, a sharp 11, a 13, or a flat 13—yes, this is all good, but there’s also the other, more interesting thing that’s happening, which is that your fingers are accruing memory.
You want to trust your fingers above everything else: they can remember way more than your brain can, like how clustering tightly or extending earnestly can evoke particular emotions, and your arms remember what it feels like to waterfall down the circle of fifths, and your pointer and middle fingers voicelessly long for the trembling urgency of a trill between the leading tone and its liege, the home, the tonic. Your fingers will take you home, and away from it, and through thickening woods of neighboring keys, and they will dazzle you, and inspire you, and what’s best of all is that you will not even be thinking about any of this: if everything goes right, you will be loosening into rareified air, unribboning into tidal sensation.
Some resources I return to again and again: