Every part of every drum tells a story. Some parts are short and sweet, and if they overstay their welcome, you end up with a very different message than you originally meant to tell. Pure chatter. Some parts are very long winded, and you won't really know what they're talking about unless you give them a chance to speak their minds.
Traditional gates treat all of these parts the same, requiring a compromise and never really letting you narrate the way you'd like to.
MGB allows you to set the timing of each frequency band of a drum separately, for instance letting the lows of a tom ring out gloriously, while shutting off the high end quickly, giving you all the attack and "splat" you want without letting the cymbals ruin your mix.
The traditional way of doing this by chaining many gates and side chains is avoided in one, easy, convenient and informative package using MBG.
In addition, each band can be mixed and processed separately so every band has its own particular enhancement(s) without messing up the others.
Set the detector to the proper frequency range of the drum in question.
Set the crossover points to zero in on the parts of the frequency spectrum you want to behave in particular ways.
Remember, there is a mute control per band, and since so often, mixing is about crating space, you may be lowering or muting entire bands to really clean up a mix.
Set the hold and release controls long enough to let the tones you want thru and short enough in other frequency ranges to shut the unwanted bleed off before it makes trouble.
Why not just low pass(or high pass, or otherwise EQ) the offensive section out?
Lets take the holy grail of all rejection problems, the tom tom, played by an inexperienced drummer, who also happens to have his cymbals only a few inches away from them, AND has to bash the cymbals before, during and after that tom fill.
An impossible task right? Time to just give up and trigger it...
Wait, even THAT won't work as there is far too much hash in all that noise. You'll have to MIDI it in by hand or drop trigger pulses. Good thing you are being paid by the hour right? Oh wait, by song? Starting to rethink your poor career choices now?
But wait, there's MBG:
1. Set the detector to the resonant peak of that tom.
2. Set the threshold to just open on the actual hits.
3. Solo the low band and use the hold and release times to give you the nice, long decay of boooooooooom as the tom rings out naturally.
4. Unsolo the low band and set the high band just long enough to give you the wet "splat" of the stick hit and then quickly shut it down before the cymbals start to ruin that tom sound.
5. Set the mid band to taste depending on how much space is in the mix and what exactly you want to do with it (again, in dense mixes, you might just mute this band!).
6. If you want even more control, use the separate outputs to, for instance, send the high band out to an exciter, the mid band out to a reverb and the low band out to a subharmonic synth.