It depends a bit on one’s definition of what composing music is, doesn’t it? If by ‘composing music’ you mean that you should be able to write down, as accurately as possible, all the essentials that define a piece of music (its notes, timbres, tempo, dynamics and such) — i.o.w. the traditional, conventional idea of what composing music is all about — than yes, I can imagine that pencil and paper (or some satisfying digital equivalent) would be the first and most important stage of the composing work.
But this being the 21st century and all, and our tools to make music with having developed, changed and expanded on enormously in recent decades, ‘composing music’ might well have come to mean something very different for some people. Me, I sort of lean towards the definition: filling a time slot with audio organized in a way that makes musical sense to me. And audio, in my definition, can be anything. Likewise, ‘musical sense’ is a very broad term.
I have pieces that combine traditionally composed sections (often originating during piano playing sessions) with material that can only be generated (following my instructions) by a well-stuffed DAW and that can’t be written down in any of the existing musical codes either. Composing, to me, can just as well mean opening a filter, inserting a delay, picking a pulse wave instead of a sawtooth wave, or distorting a reverb ..., than writing a melody, deciding on an harmonic progression, laying out the structure, orchestrating a rhythm, or writing some counterpoint. And in my view of what composing music is or can be, there’s no musical hierarchy between any of these skills or creative activities either.
I think one, being totally honest with oneself and guided by one's own personality rather than by some prevailing norm or tradition, should choose and learn the tools — whatever these may be — that help prevent the contingency of being unable to express oneself or getting in a creative cul de sac. If that means learning to play the piano well, then that’s what you gotta do. No mercy, no excuses. If it means studying the theory of composition and orchestration, then study you must. In earnest. If it means becoming intimately familiar and comfortable with the ins and outs of, say, Omnisphere or NI Reaktor, then that is where the challenge lies that you have to face. Again, and always: with complete commitment.
I mentioned ‘being honest with yourself’ in the previous paragraph: the great thing about this is that it will make the road, or roads, which you have to follow unignorably visible.
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