Hi. I can't point to you any of theoretical sourses on mixing. But for
practical tips and techniqes the free sourses could be:
- Internet: check out sites like http://www.looperman.com, http://www.mp3-mixer.com and the like;
- Public/college libraries. Some of them have the magazines like
Recording, Homerecording ecc many years back. Although they are
full of annoying ads, there's plenty of useful info as well.
- Records produced by great engineers. Just listen how it is done.
Cheers,
Costy.

JEEZ theres a technical name for everything! This question is something that can only be answered by subjective listening ,trial and error.Its what mixers(i am one)learn over the years.It becomes a second nature kinda thing and a sort of signature.Each person hears sonic three dimensions in a different way and has a myriad of ways to achieve it after years of practice.

I sound like I'm trying to avoid telling my secrets! Not the case at all.I will say, I nevr reach for the reverbs or the delays FIRST to create space.I envision the way the sound might be coming off a stage with me in the center 12th row.I listen for things above and below....front and back...left and right....I will pan the instruments accordingly and use the effects to 'suggest' a larger width on the pallette.I use EQ for the front and back in conjunction with the fader rides for a particular instrument.BUT....none of this is EVER set in stonethisworkseverytime! Thats why practice makes...er....better.