Doing patches for 4-op synths should feel quite natural after a while, just like some of you learned subtractive sound design from wondering what the hell was going on to modeling acoustic instruments. It might take longer, since FM doesn't have as obvious natural metaphors (like filters), and of course it doesn't help that most FM synths are kind of tedious to work with. Video game FM chips have just the right complexity, and Shiru's instrument editor is _really_ good.
And you are crazy to program a TX81z from the front panel! I cry whenever I even need to setup a performance.
can any of you FM guys explain through an example? for instance, getting a brass or an electric guitar sound?
I will try to get back to you tonight or maybe tomorrow. A brass example is perfect for a beginner, I think.