When composing music, I often visualize a landscape of musical textures. Underneath everything is a pastel wash, often called a pad. This background sound is very quiet - just enough to cover the noise floor. It tingles up into the main sound like the leaves of grass in this picture. It blends and supports the other things that you hear in the composition.
The main sound - the essence of the melody - is played with sounds that are central to the listener's attention. These are the trees in the photo. The melody is stated and re-stated and modified with chord progressions that parallel the pad.
The bass and drum sounds provide a background, like the mountains above. They support the sound but usually don't overwhelm it. For those really dramatic pieces, there might be might be crags and rock outcroppings, but this picture represents the softer, more tranquil side of music.
Harmonies and descants float like clouds in the skies with accents of light and beauty. It seems that much more work goes into crafting these parts. They must fit perfectly if they are to make a musical piece of integrated beauty.
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