Mixing my SFX session on ProTools HD-Control 24s, in the 5.1 Surround Sound Lab.
One of the techniques I’ve learned from Sound Designer, Steve Smith, is to give multiple frequency ranges for SFX. I.E., when assembling the sounds for an impact of a body fall, always be sure to have a Low, Med, and High-end sound effect option on separate tracks, and mixed together as one sound. Not only does having a wider range of frequencies give fullness to a sound effect, it allows the mixer options if they have competing frequencies in the Music, Foley, SPFX, etc.
I.E., if the music has a low-end drum part at the same time as your low-end body fall, you’re likely to see your SFX cut, because of a doubling of Low-end frequencies that will end up clouding the final mix. If you give frequency rich Low,Med, and High-end sounds on multiple tracks, you give the Mixer variety to use the Med and High-end part of your Impact, which will give you a greater chance of hearing your SFX in the final mix.