One thing I think you always have to keep in mind in this situation is that you're writing for rock, pop, soul and/or R&B, NOT jazz. And depending on the period and the genre, you'll find that a huge amount of what you write will be unisons with some (only) occasional voiced out things to add emphasis. On a ballad, voicing big lush extended chords behind the chorus or to set up the bridge can be really effective. But on an uptempo pop or r&b tune, voicing fast moving lines in close harmony sounds cheesy as hell and just sounds out of place. Of course it always depends on the situation and there is no real right or wrong way, just your personal taste.
Some of the most classic horn writing you'll hear is from James Brown, Ohio Players, The Commodores, Tower of Power, Earth Wind & Fire, the Brecker Brothers etc... the list goes on and on. (The Dap Kings are great too) Since you're playing someone else's music, and many of those horn lines are so familiar they've become part of the song, you may as well just transcribe them directly as originally played and score it out for the section.
As a guy who subs a lot in several different bands and on several different horns, I can firsthand say that if I show up on your gig and you have a book for me that's well arranged and organized I'm going to like you and the gig a lot more than if I'm just expected to wing it. Especially if you're doing esoteric or very intricate arrangements.
I have done several jobs recently, in major venues, where I've shown up to play Bari in a horn section behind what is supposedly an otherwise very professional organization only to be told "sorry, there's no Bari book, so you'll just have to transpose the second tenor or read the trombone parts." And my perennial favorite: "Oh, just make something up." And of course I've done it, BUT nothing tells me how indifferent you are to my presence on your gig like not showing me the same courtesy you show the other players by not having a book for me! Talk about being an afterthought!
There will be a large amount of the standard repertoire that any decent horn player should just know. But it's also one thing if you're playing with the same four guys five nights a week, and completely another if you've never seen these guys before and you have to make music with them tonight. Experience and professionalism go a long way, but preparation and getting everyone on the same page - literally - will serve you as well or better.
Just my $0.02 worth.
Peace,
John
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John Isley
Saxophones, EWI, Composer, Arranger
www.johnisley.com
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