Mix Automations in Orchestral Music

Recording orchestral concert music vs. recording an orchestra for games or movies has grown apart quite considerably over the last few decades. Even though the technical approach is relatively similar, for instance considering the basic microphone strategy, there has been quite a development regarding the use of overdubbing, room manipualtion and alternative micing in the game/film world.

Similarly, approaches to mixing these recordings have grown apart. One of these differences is mix automation. In short, mix automation means to adjust the levels of certain signals or effects dynamically over the course of a track. 

In traditional orchestral recording, the purist approach would be to only set the levels once, without as little added effects as possible and do not change these anymore and by that preserving the natural balancing of the orchestra as much as possible. Some mix engineers still apply this school of thought when recording scores today. And in general, this could be considered a good starting point.

Well written and performed music for orchestra should be balanced in itself and not require to adjust levels to fix balancing. Besides, with real orchestras there usually is only a very narrow path to actually adjust levels. For instance, let's say there is a solo flute that is too soft on top of a string section. In many cases, both elements will have been recorded simultaneously so the main microphones carry the signal of the strings and flute at the same time so there is no rebalancing possible on those. There will however be a close mic on the flute that picks up mainly the flute. Boosting this signal however also boosts the close mic characteristics of that instrument making it stick out and not feel like it is playing together with the orchestra. So this works only in a limited range before it gets too obvious and unnatural.

This only could be resolved by having recorded the strings and flute in separate passes which comes with a set of new problems.

However, score mixing these days still quite often relies on mix automation. Depending on the style of music, there is quite some improvement of dramaturgy by dynamically balancing the close mics against the far mics. Imagine a musical buildup, that starts small and intimate and grows into a full blown tutti. It might be beneficial to start this section with more focus on the close mics and gradually increase the level of the far mics so the sound "grows" with the music.

Also, selectively boosting close mics and adding additional reverb on it during a solo etc. is quite common. The dogmatic approach of orchestral mixing has been replaced by more or less "anything goes", including more "destructive" effects. And in spite of what some seasoned mixing engineers say, there's not much that can go dramatically wrong in an orchestral mix. If you have a considerable listening experience and know what sound you want, you can easily catch those few pitfalls. As long as you like the sound, it is fine.

With sample productions, the flexibility becomes even bigger as you effectively have every single instrument isolated and can rebalance things in whatever way you like. 

However it should be noted that the more you do this, the further away from a traditional orchestral sound you will get. Fixing balancing through mix and not through orchestration creates a considerably different sound. There is an inherent danger when overdoing this that the mix will fall apart and it will sound like several instruments are playing on their own without actually playing together. But even that could be a desired effect.

In general, whatever gets you closer to the sound that you want is okay to apply in the mix. I have had several discussions in my life with seasoned recording and mixing engineers. Especially here in Germany where there is a long tradition of classical recordings, some of them might be very reluctant to try out certain things.

In general, you should not feel reluctant to write in mix automation etc. just because it "shouldn't be done". Even with more traditional sounding scores, you get the occasional "fix in the mix" strategies that are applied. 

If you rely on external mixing engineers, you should however make sure that whoever you pick has experience in the style of music that you are going for. It is not a great idea to hire someone who is doing classical mixes for a film score and even worse, hiring someone who only does band/pop mixes for an orchestral score.