Just like light, improvising — and more specifically, taking a solo — is not just one thing.
A lot of players think taking a great improvised solo is either fully spontaneous, channeling the muse out of nowhere, or fully prepared, written out beforehand and played the same way every time. But really it is the interplay between both.
Two Things at Once
When taking a solo, there is a reliance on lots of preparation, practice, and even some predictable and pre-thought-out techniques and devices. But there is also a reliance on curiosity, spontaneity, the ability to be present and react — a willingness to depart and be drawn away from the place you thought it might go.
The trick about these two views is that they both take practice.
You can and should practice material, theory, technique, scales, and more for the real thing.
And, oddly enough, you can and should also practice spontaneity — the ability to be curious, the beginner's mindset that can lead to novel forms of expression.
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