mighty thor
Banned
What you want to accomplish should be tackled in the tracking stage. It's the playing, the speed, the dynamics,the delivery, etc...that make a song "mellow" or not. Like Boulder said, it's too late to try to create a mood by the time you get to mixing.
Many bands use the same gear to record, yet still manage to create different moods. It's about the tune, the playing, etc....
"Stairway to Heaven", "Misty Mountain Hop", and "Black Dog" are all on the same album, are played using the same instruments, probably all recorded in the same studio by the same musicians. Yet, they all have completely different moods to them.
I think you're making a typical noob mistake by hoping there are "tricks" and "secrets" that go on in the studio to create what should be created right at the source, AKA by the musicians and their instruments.
Very good example. Id say you can create slightly different mixes but other than replacing tracks altogether, like a dance mix, you aren't going to alter the original mood of the song very much.