Basic Studio Mixing
Much has been written about mixing from an engineer's point of view, not so much from a producer's point of view however. Many years ago, before the modern era of multitrack, recording and mixing were part of the same process. You had to get a good balance between the voices and instruments at the session because there was no way of making any adjustments later. In fact much orchestral music is recorded in the same way today, directly to stereo. Mixing directly to stereo is also very common for today's popular music, in live PA work and broadcasting. The reason that it is possible to do without a multitrack stage in these situations is that the engineer knows before even one fader has been lifted what the final recording should sound like - as close to the original as possible. Since skilled engineers can achieve such remarkable results, you might wonder why we need a multitrack stage at all. The answer is that it allows much more attention to be paid to each element of the recording in terms of sound quality, musicality and creativity. Paying as much attention to these three aspects as they deserve is why recording takes so long and why you have to put so much effort into it.
The producer should ideally start the mixing process as soon as the project gets off the ground. He should have an idea of the sound he is aiming for, allowing a certain amount of scope for creativity depending on the nature of the project, the requirement for creativity sometimes being great, sometimes comparitively modest. If it is a dance music record, for instance, then the producer will understand the style well enough to know the elements of the music that his audience demand, and will add to those elements new and different sounds and textures to push the style further into the future. If the producer knows how every step of the preparation and recording process is going to contribute to the final mix, then the mixing stage should be straightforward and successful. This means, among other things, getting the arrangement right and selecting the right sounds, making sure the musicians are playing in time and in tune, obtaining a good performance from the singer by whatever means necessary. If there is a problem in any of these areas, then you can only turn a deaf ear to it for so long - until the mix in fact. Any problems present on the tape at the mixing stage will have to be disguised or covered up. Those problems should have been corrected as soon as they occurred.
As more and more tracks are being added to the recording during the overdubbing stage, then the engineer and producer will be working with a mix that may bear a passing resemblance to the finished product - the monitor mix. The monitor mix is what you listen to during the recording process, and is usually thought of as a rough guide to what is already on the tape. Good enough so that the musicians can get a proper feel for the music, and good enough to tell the producer how the recording is shaping up. It depends on the type of mixing console you are using, but some have only very basic monitor facilities - perhaps just level, pan and a couple of auxiliary sends. This means that you can't do anything in the monitor mix apart from set how loud each instrument is, where it appears in the stereo image, and how much reverb it has (the other aux will be used to send foldback to the musicians' headphones). In fact this is not a bad way of working because you will hear exactly what is on the tape as you progress through the recording. Hopefully you will be perfecting each sound as it is created, and you will add new sounds in context with what is already there. If the monitor mix sounds good, then you can be sure the final mix will sound great.
This simple style of monitor mixing has its merits, but large scale consoles offer vastly more sophisticated monitoring facilities. You can create a mix on the monitors using EQ, compression, gating, and everything else that is part of modern studio technique. If you regard the monitor mix as something temporary, but you - and the engineer - then proceed to use all of these facilities, you may find yourself in big trouble by the time you flip the multitrack onto the big faders and start to mix from flat because the sound will be totally different. But you wouldn't do that of course. By the time you graduate to SSL or Neve class studios, you will have learnt the first rule of recording: Nothing less than 100% effort is good enough. You should regard everything you do as being part of the finished product and make it as perfect as possible. Even if it is only something you do as an experiment or as a temporary reference, then the fact that you have done it right will at least tell you something if it didn't work quite as well as you had hoped, and what you have tried and discarded will still influence the mix. This includes the monitor mix. With a console that only has rudimentary monitoring facilities you will tend to want to perfect everything on tape. With a console that has sophisticated monitoring facilities, you will record a good clean sound on tape, and then anything that you do to the monitor mix will become part of the final mix. The console will allow you to do this so you don't have to start from scratch when the overdubs are finished. In fact you can do this with any console that has enough channels. It is very common once a few tracks have been recorded to route the multitrack to the channel faders and start to mix as overdubs progress. This way you never get to a point when you say, "Right that's finished, let's clear the desk and start to mix". You just come to a realization that everything is done and all that is needed is a little polishing here and there.
From another point of view
There are many ways to make a record, and I can imagine some producers reading the above and thinking what a load of bull it is. There is another style of recording where the approach to an album is to record all the basic tracks, then to overdub all the other instruments and vocals, then to take a few days break before starting to mix the whole lot. The disadvantage of working a song at a time all the way from basic tracks to mix is that you can easily lose perspective. People on average listen to each record they buy about six times before they store it in a cardboard box in the attic, give it to an unloved relative or donate it to a charity jumble sale. The producer of the record has to listen to it something more like six hundred times - or more - during the recording and mixing process, and in the same way as familiarity breeds contempt, over-familiarity with a song and the recording of that song means that you can't judge it in the same way as a punter would. Taking a break between recording and mixing means that you can come back to the song with a fresh pair of ears and hear very clearly which are the good bits that need to be brought out, and which elements play an important but subservient role. If this is the philosophy of mixing that appeals to you more strongly, then you should be aware that it would probably be a waste of time working on an elaborate monitor mix. You could store it on a console with recall facilities, but that would negate the advantages of taking a break before mixing. A simple monitor mix is probably the best idea.
Still on the subject of monitor mixes, another common thing to do is to swap between songs during overdubbing according to which one you and the band feel you have most enthusiasm for at the moment. Or you may have booked a session player who you want on more than one song, so he might as well do them all in the same session. This means locating to each song on the multitrack and resetting the monitor mix on the console. If you confine yourself to level/pan/reverb monitor mixes then it won't take too long to set up. Sometimes however, during the later stages of overdubbing, you may feel that the mix you are hearing sounds really great, just by chance, and you would like to keep it as a reference for when you start mixing proper. In this case it's a simple matter to copy the monitor mix onto a DAT or CDR so you can check it later. With so few variable elements, it is pretty easy for a skilled engineer to reconstruct the mix almost exactly, and then you can go ahead and improve it still further.
How to get a good mix
Simple. Use a good engineer and stay clear! I mentioned earlier in the series that engineers acquire a vast amount of experience of working with music and sound, and they are the people who should be operating the faders - not the producer, unless the producer comes from an engineering background of course. If the producer sits in the studio from the moment the first fader is raised all the way through to the finish, he will be nothing but an inhibition for the engineer who would really like to get on and tinker with the sounds and try out lots of ideas, many of which might not work. So this will be a good time for you to take a walk in the fresh air and clear your mind ready to make an objective judgement on how the mix is progressing, two or three hours after you left the engineer alone with it. You may leave behind a few ideas or guidelines, or you may even encourage the engineer to go wild and try out some crazy things. When you return, you will hear your production in all its glory and you will be able to advise on what it is you want more of, what you want less of, or you could even say that it is entirely wrong and you want to start again. An experienced engineer accepts that the producer is in charge and won't take offence (he just won't work with you again!).
A trickier question is what makes a good mix. It's especially tricky for the engineer who has to learn every detail of how to get a good mix, since nothing will happen by its own accord. A producer on the other hand doesn't need to know the details but has to be able to recognise when something is right, and offer meaningful comments when it isn't. You need to keep in mind the purpose of the mix. Is it a dance floor mix that should sound great on a club PA? Or is it intended for CD listening at home? A radio mix should emphasise the 'buy me' factor, whatever it is that will attract the listener to the singles counter of the record store. The engineer will always sit in the optimum listening position directly between the speakers while mixing, but you will probably wander around the room. This is so you have the opportunity to hear the mix in less than perfect conditions, which is exactly the way the end user will hear it. Either they will be in a club with the bass turned up to stomach pounding volume, or they have a rubbishy home hifi with the speakers wired out of phase, or they are listening on a car radio in heavy traffic, with a hole in the exhaust. Your mix has to sell the song in each of these situations so while the engineer considers the finer points which will only be appreciated by those with good quality home stereo systems or a decent pair of headphones, you will be looking for the overall impact. If the mix sounds good from any listening position in the control room, then it probably is good. All studios have two or more pairs of monitors so you can check the mix on very high quality speakers or on the console-mounted near fields. You can also have a cassette copy made so you can check the mix on a cheap stereo system, on a Walkman or in the car. The more ways you can listen to the mix the better.