Im trying to write a sort of big brass fanfare type intro to a song and I need some help with the writing. Any ideas on how to achieve this?
Well you say big brass, so write music for a brass ensemble. How you are going to perform this is beyond me, unless you know a brass band.
^ i was going to say "write it using a pencil on a music staff"
Its easy, give the french horn section the chords and ensure they hit those chords right on beat the beat, thatll give the sound some force to it. Tuba/trombome/euphonium whatever you may have, long, low suspended notes, preferably playing root and 5th. That'll build out the chords, give it a much fatter sound. Do whatever you want with trumpets, I'd usually give them a subtle melody accompanying the french horn part. That seems to work fine, I've written some fairly epic movements with that simple arrangement technique. If you want to talk some more about it add me and I'll see what I can tell you.