Try googling "mastering compression". There is tons of stuff online concerning compression since it's a very involved topic. But well worth learning what you can as compression is pretty much expected nowadays in modern music, and will give your projects that extra shine. This was a personal hurdle of my own as well and I'm sure as rain I still don't always utilize compression to it's best potential...
For your project though, my first suggestion to you is to zero out all of your tracks so you're basically starting over with your mix. Put a compressor on your master bus and make sure all of your tracks are going through it. Then mix with the compressor on. A typical ratio is 2:1, but you should learn what each knob is supposed to do on your own. That's way too much information to cover here. In this scenario, you are in effect mastering as you go along. EQ'ing on your main bus is also common (plus the EQ that you've done per track hopefully to give every instrument it's own little sonic space). If you intend to give this to a master engineer later, then yes you would mix without any compression on the main bus, and let him or her add that later (in fact they get a little irritated if you hand them something that already has compression on the main bus, they can't really do their job at that point). However that route is expensive and really not necessary as you can get near commercial quality with a little bit of work, and A/B'ing (taking a commercial CD you like the sound of and trying to get similar volume and sound). This can be frustrating as h#ll just to warn you. You may not be able to get quite to their volume without it sounding terrible. It's better to be quieter and not squash everything instead. As Mazz said, it's going to get compressed some more if the track is broadcast anyway, so don't be too concerned about the volume (within reason of course). The more important thing is that the overall mix is well balanced and clear.
My second suggestion is to try as many different bus compressor plug-ins as you can get your hands on. They're not created equal. Hardware-wise they certainly weren't and most compression software nowadays is trying to emulate one kind of hardware compressor or another. I can guarantee you most members have compressor plug-ins they really love (ask around I'm sure they'll tell you
), and others that make them gag. For example I have something called Boost that was included with my DAW. It's ok for quick and dirty compression and it's all automatic (only two knobs involved?!). However it s#cks royally at being a bus compressor. It's anything but transparent. That's one of the main things you want which means you don't hear the compressor kicking in and out except in extreme circumstances (or if you're doing it intentionally because you want that effect for some reason). It's just louder with all the tracks performing as a whole (the glue that you'll hear people talk about occasionally).Hope that helps for whatever it's worth. Sorry if this was a little long. Happy googling!
- Roger
