I would rather mix one track at a time, so that any lessons I learn can be applied to the next mix, and the next and so on.
I'd second Matt on that one. It may mean that you end up redoing the first couple of mixes with the benefit of hindsight, but I think overall it's probably the best option if you're still feeling your way a little bit with the mixing side of things.
How do you make an album sound fairly consistent throughout. I mean, for some styles of music (metal, pop punk etc) the drums sound very similar, the guitars sound very similar and all the levels of each instrument are the same throughout.
After getting the balance right for one song how to you get the next to sound the same... and then the next. This is something I have trouble with and I am recording an album for a punk band next week!
It's no different than when you're mixing anything -- you have to reference your work against any other material you want consistency with. Often that will of course be commercial releases with which you want your work to compete, but it can just as easily be other mixes you've done which are destined for the same record. If you make sure to do that, then everything else should sort itself out in the long run.
My advice for that would be that similar effects will be used in the mix and this usually will give a mix a lot of character or not (depends what you are after I guess).
I do tend to keep the main send effects I used for the first mix available for the second if I'm working on several things for one artist -- as long as those effects met with their approval first time round! That does help to give some conformity to the sound. However, The Elf does make a good point that there are perfectly valid aesthetic reasons for not wanting to make all the tracks sound the same, so you should still try to make each track shine on its own terms. If that means using completely different mixing strategies, then so be it.
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