| Since i play in various groups and settings, the creative processes can be quite different:
In my ska-punk band, our lead singer writes the songs. He'll teach it to us in a rehearsal, and for the first few rehearsals and shows of playing a new song I improvise my parts around the chords, figuring out what sounds good. Occasionally I'll offer suggestions like harmonized horn parts, etc. which the singer will then turn down immediately until the rest of the band convinces him to hear it once, after which he generally likes it.
I'm predominately a jazz upright player, and most of my working gigs are small combo jazz things at small clubs. Depending on the group we usually stick to standards (while trying to avoid reverting to The Real Book) and sometimes play modern jazz tunes that we transcribe and bring to a rehearsal. I've found that vocalists like to prearrange things way more than instrumentalists, so we generally have way more rehearsals if there's a vocalist included.
My own compositions have gone mostly unheard over the years, since I've only thought a few of them to be good enough to bring to a group. I've found I compose way better under time pressure, so if there isn't a deadline imposed on me externally then I try to put one on myself. I don't really have a method for composition, ideas will randomly come to me, and most of them are awful.
__________________
Please do not shoot the bassist. He's doing his best.
| 
