Three things I avoid when mixing in 4-channel:
- Criss-Cross mixing. ie: Drum kit in Front Left and Back Right. NO. That's not how a drum kit is set up.
- Lead Vocal in all 4 channels. While it can sound good; I prefer to maintain focus with the front channels.
- Channels with Extended silence or Quad Black Holes. Unless you're building tension before a crescendo, you've got 4 channels - USE them.
My own personal S.O.P. is drums in the front 30Ā° narrow spread unless tracks available can dictate a more engaging layout. Bass front center (obvs). Other percussive instruments in the back corners (conga, shaker, tambs, etc.) Depending on tracks available, rhythm instruments in rears, leads or more exciting instruments in the front. Four or more instruments is always a dream come true. Backing vocals generally in the rear. I do enjoy putting drum kit echo and vocal echo in the rears, too in an attempt to fatten up the mix.
Playing with drums, in my attempt to make Elvis' "Burning Love" sound more like a vintage Quad Elvis mix.... with only 3 tracks available I put the kicker back center, the snare FL and the hi-hat/overheads FR. My thought process was to emulate the mix of Madison Square Garden or even the Waylon Jennings Q8 which both feature the kick drum in back center.