It's a really good idea to stagger attacks in general, even moreso with CoMB.
Many of the brass are conical instruments to begin with and are INHERENTLY "organ-y" to begin with. When attacks coincide and/or conical instrumentsare mixed with cylindrical instruments, you can get one big organ stop.
Also see below.
Another thread mentioned that the forum needs a lesson or two on "band-strating"--orchestrating for band.
I'll start briefly, and hope that someone whose bona fides exceed mine will take over.
A WIND ENSEMBLE IS NOT AN ORCHESTRA. 1.THERE IS LESS TIMBRAL DIVERSITY IN THE WIND ENSEMBLE. That places a bit more burden upon a composer/arranger/sequencer to highlight whatever diversity there is. Some of the stuff that composers/arrangers/orchestrators can "get away with" in orchestra because of the diversity of sound will be exposed in the more homogeneous environment of the band.
I know it sounds obvious, but here are the implications.
2. YOU ARE, IN ESSENCE, DEALING WITH ORGAN STOPS IN A WIND ENSEMBLE. There are no strings to create contrasts. You are dealing in a band with closed or open pipes, and cylindrical or conical pipes. It isn't surprising, then, that an "organ-y" sound is possible.
3."SECTIONS" exist in a wind ensemble that don't exist in an orchestra. Try to make your sections as varied as possible. I only use the section instruments in CoMB as a reinforcer when I need a big sound. I vastly prefer the ensemble building approach. Even though I work in notation, I take great care to stagger attacks in every track. Another useful idea is to make liberal use of var1 and var2 and randomize velocities, especially in notey passages. Nobody's attacks are ever totally coincident or totally consistent. So even though I may have two clarinets on the same part, I enter the notes, clone the track, apply randomization of note-ons and -offs to each track, randomize the velocities in each track and apply a dose of VAR1 and VAR2 to each track. That way the organ effect is minimized and I achieve a sound that mimics two skilled clarinetists sitting next to one another playing the same part.
4. BANDS TEND TO BE MORE "IN THE MID REGISTER" than orchestras. I don't know if that's the fault of writers or the instruments themselves, but bands seem to be very light in uppers and lowers and heavier in the middle that orchestras. that may also contribute to the organ effect. That's also a by-product of the "no-strings" state of affairs.
Well, I have to split for work now, so I leave people with this--perhaps to be expanded later:
1. STAGGER ATTACKS!
2. Use heavier velocity on attacked notes--let your ear guide
3. Vary velocity, even within the parameters of individual dynamics
4. Liberal use of VAR1 and VAR2
5. Build your ensemble