Also, when an orchestra plays a stab like this, I often hear a slight fall in pitch (like a very fast slide down), particularly in the strings. Is there a technical name for this or an articulation which replicates it?
This "slight fall in pitch (like a very fast slide downeffect" you mention, I fake by arranging the note off's like a stair ---> the highest notes, i.e. the piccolo cuts off first, the lowest instrument like contrabass last. This produces a similar slide down effect as in the concert hall. I can very well be that the contrabass sounds 200 millisecond or more longer then the violins. But the most power you get by fusing some appropriate reverbration with the dry sound.
Also, when I use stabs for contemporary rap or hiphop, I print several slightly different stabs, to add a bit of variation to the otherwise without much ground clearance but a lot of spiritual road adherence R&B songs
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