If you're learning jazz piano and are at the stage where you know the basic 7th chords and enjoy playing a few tunes, it can be daunting to make the leap to playing rootless chord voicings. Not only do the now-standard 'A and B' rootless voicings have 9ths and 13ths in them, but they're so different from root position 7th chords that it may seem like you have to forget everything you already know in order to play them.
Although at some point you will have to do some serious "woodshedding" on A and B voicings, it often a lot better to proceed more gradually, and relate each new voicing to what you already know. Another advantage of this approach is that it won't slow you down much. You can still play the tunes you know without having to stop and think about every chord. (That's no fun!!!)
Here's a simple way to move from basic 7th chords to fancier voicings:
Play any 7th chord, in either hand, and in any inversion. Now simply identify the chord root, lift up that finger, and play the 9th instead. It's one note to the right of the root.
So if you're playing Cmaj7 (C, E, G, B), you'll play a D, which is the 9th, instead of the root, C. Your new voicing will be: D, E, G, B.
This is a great intermediate step between playing the basic 7th chords and the formulaic A and B voicings.
Besides being more "do-able" at your level, you'll also develop the ability to think these things through for yourself and see the relationship between 2 different versions of the same chord and how they lay on the keyboard. It's an intermediate step and "advanced" at the same time, since this is how advanced jazz pianists think. They're constantly evaluating what's the best voicing for any particular situation, and not just relying on a formula, even one as good as A and B chord voicings.
Give it a try on a few tunes!
I know what you mean, Frank, because I went through the same phase with my own piano playing. What helped me was to gradually include 9ths in my playing, without changing all the voicings at the same time which can be overwhelming. Sometimes, when you can, play the 9th instead of the root in a 7th chord. It's only one note to the right so it's "do-able." That's a good start to moving in the direction you hear in your head.
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