Here's another of my recording related rants. A friend of mine just joined a new band who has just given $1600 to a local "studio" just to master 7 songs. The studio [that has a very nice website! Looks totally pro!] is a long room practically anechoic in nature due to the amount of foam he's covered his walls with. I should know, it's all the foam I had in my old studio back in Vancouver, BC that I sold to some youngster when I moved over here to Vancouver Island.

Anyway, that guys mixes sound ok in his studio and do not translate anywhere else. His prices are astronomical but he gets business because there is a lot of good talent out this way who don't want to compromise their quality and will/do pay top dollar for recording. I'm not in that game anymore because as I'm sure many of you know, musicains are difficult people to deal with and everyone has a different idea of what's good... and I get mad at lazy people who tell me just to fix it with protools.

I thought I'd make a list of reasons you shouldn't mix and master at the same studio.

Quality mastering requires more than nearfield monitoring. You need big speakers, high spls, specialized equipment etc.

A real mastering lab will definitely have a flat frequency response at the mix position. So they will be hearing a more accurate picture of what it really sounds like than your average studio.
If you have flaws in your monitoring setup in the mixing studio, and you master at the same place, those errors won't be caught.

Let me tell you what most engineers will do to a song in a small time recording studio. They will put a plugin eq before a limiting plugin. Then they will set the limiter to kill, destroying many of the dynamics of your music. And then they will use that eq get rid of any weird frequencies that jump out when they compress that hard. And then they might boost up the bass a little or make the high end shine. It takes maybe 5 minutes. There's no critical analysis done here. There's no amazing feats of art and science fusion.

I will say that in my experience, getting music mastered by a quality mastering house will take your existing mix and add a full 20% of awesome to it. It's not cheap, but it's not the most expensive thing you could do. It might be the difference between "making it" and not. Now, I don't believe everything should be mastered. If you just record at home and want to get some music up there on the web, by all means throw a compressor and there to pump up the volume. But for an important project destined for a cd release, the money is well worth spending.