Mixdown
After the overdubs are completed you will need to "mix down" your tracks to stereo or whatever your final output configuration will be (surround, mono, whatever). This is your final master and will be where you want to get everything sounding exactly right.
Before you can get to the real nuts and bolts of mixing you need to do some organizational and setup things like choosing some reverbs or compressors and installing them in obvious places, and clean up your tracks so they only are showing waveform displays while they actually are playing. A perfect example of this is tom tom tracks. The amount of time they actually get played during a song is relatively small so for the rest of the time the tom mics are just picking of the other drums and cymbals along with the sympathetic ringing of the toms themselves. So we delete those tracks except when they’re being played. The same is done for all the rest of the guitar tracks (gets rid of amp hiss and little string noises prior to entrances), vocals (gets rid of headphone bleed, clothing noises, throat clearings and lip smacks).
This is what the mixer looks like in Digital Performer. It has all the standard features you’d expect in a hardware mixer; automated faders, pan pots, auxiliary sends to effects, insert points, master channel etc. It functions pretty much as you expect it would, except that since it is just software you don’t have to be at the mercy of how much hardware you have (or don’t have) lying around. A more thorough explanation of how a software mixer and plug-ins work is on Tech Note #2
Once you have done all your track cleaning, you can begin the actual mixdown.
Mixing essentially has three stages. First, you listen to each recorded track by itself and adjust the sound so that the instrument (or whatever) sounds the way you want. This usually involves adjusting the treble/midrange/bass and doing some kind of dynamics control (compression/lmiting) and making a preliminary estimate as to how loud you might want that element in the mix.
Next, effects are added. Effects are things like reverbs, delays, flangers, phasers, pitch shifting, and all the other wonderful "toys" that modern technology has provided for us. There are some truly bizarre and wonderful plug ins to try when you’re looking for that something extra but aren’t really sure what… Volume balances between tracks and instruments are constantly being tweaked.
The third part of mixdown is the actual final balancing of all the tracks together to get the best blend during each moment of the song. We've all heard the expression that you can "Fix it in the Mix!!!". To some extent this is true, but only certain types of things can be fixed in the mix. Mixing can fix things like uneven level changes within tracks or removing unwanted parts, adjusting entrance times etc.
Mixing cannot fix things like out-of-tune guitars or bad notes and truly sloppy singing in vocals although in the computer age, we have a lot more tricks up our collective sleeves than we used to. A large range of things that used to be impossible are now possible: Single note instruments and vocals can now be tuned up on the fly, individual notes can be time-stretched or squeezed without changing the pitch to match others in a vertical stack, individual phrases or notes can be lifted from elsewhere in the recording and moved to new locations in the song.
So once your mix is designed you keep playing the song over and over, adjusting volume levels of the tracks until you arrive at a point where everything sounds good and is balanced for the whole song with a few exceptional places in some tracks. At this point the mixer automation is turned on and these “base settings” are set for all tracks for the whole song.
You then start your mix from the beginning and when you run across one of those exceptions (like a vocal line that gets lost when the singer goes into a low register, or a guitar note or chord that sticks out) you use the mixer automation to raise or lower the level to fix the problem. Continue doing this until you reach the end of the song. Start the song over and listen again, perhaps you will catch something else to be fixed. Continue this procedure until you can honestly say that everything sounds good and you can’t think of anything you would like to change. Congratulations, if it all sounds good and you don’t want to change anything, you must be done!
You then record this 2-channel mix to a stereo file which becomes your final mix master for inclusion on the CD
Tech Note #3 Evaluating your mixes out in the real world
Post Mix
By far, one of the greatest advantages of the computer-based studio is the ability to recall a complete mix environment with the click of a mouse! Because all compression, reverb and FX, volume controls take place in the computer instead of an array of outboard compressors, delays, and reverbs it can all be recalled instantly ready to make a small change.
In the historical “days of tape” you might spend as much as an hour resetting the console, patching in all the rack gear, duplicating all your old settings on each piece of gear, running the mix to be sure you haven’t overlooked something, until you’d be ready to update your mix. It was simply too time consuming (expensive) to be worth it for small changes, forcing you to be stuck with some small thing you didn’t like on your final product. But no more!
These days the mix that’s on the CD is almost never the first mix done. We have done as many as 5 or 6 mixes on some songs, with some of those updates being for single note fixes and adjustments. It only takes about 5 minutes to call up a mix, make some small tweak and roll off a new mix.
So there you have it. A computer based recording studio can be an extremely flexible, creative tool for the person who knows how to use it effectively. It takes a lot of thought and time to become an expert at using a modern studio but anyone can get good results the first time out by following the advice and hints presented here.
