As bands and crews prepare once more to plunge into the festival season it occurs to me that there are two distinct types of live sound mixing.
The first type tends to exist only at the upper reaches of the industry, where the big bands are playing arenas and stadiums. In this rarefied atmosphere the mixes will be built, tweaked and settled during extensive production rehearsals. Snapshots will be stored and the front of house mix will be consistent from the very first show to the very last, all the engineer need do is step through the snapshots whilst ensuring all is in order. This type of mixing is done on the same mixing desk every night, using the same microphones and the same PA system. The only thing that changes is the room and there's usually a team of system techs on hand to look after the PA.
The other type of mixing is where the mix is built from scratch every single day, starting with channel one and going through the channel list piecing it all together on the fly. Time is invariably limited (especially on a multi band bill) so the mix doesn't always get built to the desired level and finessing becomes a luxury. Every night there's a different mixing desk, a different PA system and a different room. The engineer will often be required to figure out the room acoustics while mixing and sometimes will even be required to mix the monitors at the same time.
Whilst both types of mixing require the same core mixing skills, in terms of channel processing and piecing it all together, they require quite different approaches and subtly different skill sets.
The first type requires the kind of meticulous attention to detail more commonly found in recording studios, where you have much more time to focus on the specific needs of each song and apply much higher levels of signal processing to produce the desired results. The bulk of the actual mixing is done prior to the tour such that when you finally hit the road you become the caretaker of the mix, tweaking where necessary but mostly just listening to ensure all is well.
The second type requires the ability to be able to put together a functioning mix quickly, to be able to respond in real time to the acoustics of the venue and make quick decisions as to how to adjust the mix to make it work in differing environments. Compromise is inevitable and flexibility is vital not just in mixing but also in terms of being able to use different equipment in different rooms night after night.
In a sense these two types of mixing represent the past and the future. Needing to build a mix from scratch every single day was very much the norm back in the analogue days but digital desks, with their total recall ability, have opened up whole new horizons of consistency and creativity in live mixing. And now the advent of smaller and cheaper digital consoles has very much blurred the lines between these two types of mixing as bands at all levels now have access to snapshots and total recall.
There is one interesting and important sub set of live mixing which many engineers will now be contemplating with a combination of nervous excitement and dread - festival sound. Someone somewhere decided that what the audience wants is a constant stream of bands with as little interruption as possible. So they did away with those cherished sound checks and insisted that bands just turn up, plug in and go. Change overs are kept to a minimum and extra crew members are hired to help drag one band off stage whilst pushing another one into position and plugging everything in. If you're lucky you get to run through all the inputs before the big hand of the clock signals the irrevocable start time of your shorter than usual set.
Assuming you're not in a position to bring in your own mixing desk (or you don't have a mature show file for the model of desk that's available) then you're going to have to throw your mix together very quickly indeed, usually during the first few songs of the set. On the plus side you're invariably outdoors so you don't have to worry about tailoring your mix to the room acoustics or battling the spectre of feedback.
This for me is the pinnacle of live mixing, a roaring hot crucible in which engineers are subject to immense pressure to come up with the goods in the shortest time possible. I love the challenge of leaping forward from a standing start and frantically trying to pull together a functioning mix rapidly. It really gets to the core of what live mixing is and forces you to finely hone your listening and decision making skills. Come the autumn, when we all go back indoors after a busy festival season, we'll all scoff at the notion of a three hour sound check and wonder why anyone could possibly need so much time (before quickly adapting and embracing the sheer splendor of sedate sound checks).
So what tips can I offer to help people through this difficult and demanding time? Well one thing experience has taught me is to go with the flow. I used to insist on resetting the desk so I could start with completely flat channels and apply the processing that I know will get the desired results rather than adopt someone else's settings. But now I'm quite happy to inherit the previous engineer's mix and adapt it to my needs, it certainly saves time. One handy tip is to look at the patch for the previous band, see which channels have similar content and which differ so you know where you're going to need to focus more of your attention in those first few moments of mixing mayhem. Certain instruments, such as drums, are going to be reasonably consistent from act to act so you can easily save time by using the existing settings, you might even discover an interesting way of processing an input by observing someone else's settings.
It's also often a good idea to sit down with the band and discuss which song they're going to start the set with, as this will have a big bearing on how easy it is to build the mix. Sometimes I've even suggested doing an extended intro to the first song where each instrument comes in gradually. This affords you a little bit of time alone with each instrument and makes the process of quickly building a coherent mix that little bit easier.
I started this article by declaring that there are two types of mixing but the truth is that the pre-production method and festival mixing represent the two extremes on a wide spectrum of live mixing. Every other show falls within these two poles so if you can master both extremes then you should be able to cope with just about anything that lies in between.