Like snowflakes, no two major scales look alike. Sure, they have the same internal structure, but because the keyboard has an asymmetrical pattern of black and white notes they all look and feel a little different.
This can be a little frustrating when you first learn all the scales (“How many sharps are in B major?”), but after a while you get used to it.
One thing you can do to become fluent in all the keys is to transpose the same thing into each one. Take a chord, melody, or pattern and learn to play it in every key. This is useful in that it forces us to confront each key in the same way. I used to spend hours doing this. (Ever try playing a Charlie Parker solo in F#?)
At some point, though, you can begin embracing the uniqueness of each key. Indeed, they all look and feel different from one another. A technique that feels natural in one key will feel awkward in another, etc. Explore this and use it to your advantage.
I found this out in a big way when I was composing the Blues Scale Etudes for my KeyboardImprov.com video course. I wanted to write an piece in each key that used the blues scale, to give students the chance to become fluent in all the keys and in a lot of different musical styles. Even so, I was surprised just how much the various keys influenced the music. In D, for example, I could write a traditional blues with “crushed” notes whereby the pianist lets their finger slide from a black to a white note, blurring the sound a little in a bluesy way. But this doesn’t work as well in E, since you can’t slide from a white to a black note. So my E Blues Scale Etude became a fast rock jam, with exciting guitar-like riffs but no crushed notes. In a similar fashion, Ab seemed well-suited for a relaxed semi-alternative rock style.
Try this for yourself. Spend some time in each key and see where each one leads you. Maybe you can stretch a 10th with your left hand on an F chord, but not while playing Db. This is fine. By all means, try to learn everything you can, but at the same time, embrace the unique features of each key. It’s fun to explore this, and it will help your music become more rich and varied.
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