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Introduction to Mixing-Through Part 10 - Latest Update 12-08

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Hello all,

I make no claims to be anything but a competent live mixer, and an out of practice one at the moment!  That said, I have always tried to approach mixing as systematically, and scientifically, as possible, and I hope that some of the rigor I needed to learn how to hear can translate into useful information for those learning the craft.

I will resist nearly every attempt to present advice that is extremely specific to an instrument or genre, as neither is terribly useful.  This is also NOT postings on how to use the routing or features of a mixing board. I will not be discussing how to keep channels from clipping, or such things.  A basic competence from reading the manual of a relevant mixer should be considered a pre-requisite for this thread.

I post this in the lounge primarily because I believe that folks here are the ones most likely to benefit from a tutorial, as well as needing to shorten their learning curve as much as possible.

I feel this first post, in what will likely be a several part series, is a discussion of the process (really mistakes) I have wrestled with since I first stepped behind a mixing board, and the evolution to a degree of competence, and (more importantly) confidence.
My History

The first mixing board I ever remember sitting behind was a Yamaha 1604.  On my first ever gig i remember seeing a button labeled "pad" and having no idea what it did, and out of panic, pressing it in on every channel!  I also remember not understanding how the channels had to go through the subgroups first.  Needless to say there was very little sound at the beginning of that gig, and what did come out was pretty quiet (due to the pads!).  Thankfully that was an amateur theater show in a small auditorium when I was early in high school!

My two points of that anecdote are:
1. everyone starts awkwardly
2. basic knowledge of how your gear functions is essential.

Next came the "get the volumes right" stage.  I merely threw up microphones and played with the faders until the placing of things felt about right.  The boards I was exposed to had little flexibility in equalization, and I was totally unsure what to do with that equalization!

These events had what I would now call "instrument balance" in that I learned to try to get the vocals on top, and make the bass sit in a pocket, etc.  What these events lacked were "spectral balance."  In other words, if an instrument was boomy or nasal, my solution was to turn it down, rather than try to balance it out with eq.

My next evolution was the "play with eq" phase.  At first I was scared of the eq! I would only turn the knobs 3-5dB and then not be able to tell any changes!  I was scared of the perception that I was somehow damaging the "purity" of the sounds.  Needless to say I had not spent any time in a recording studio at this point

After learning to turn the eq knobs a little more, I then realized "I have no idea what frequency to put my equalization at!"  I was stuck here the longest.  It takes time and practice to learn where to start with eq.

Not knowing what ranges to equalize resulted in a very haphazard mixing process.  The order of cleaning up the channels, making mix adjustments, scanning the board during the show, etc. had no structure.

Another problem in this stage was the classic mistake of trying to make everything smooth and covering a lot of frequencies when in my headphones, and then wondering why my mix is a complete and total wall of mess as soon as paid attention to the house mix again.

Working in challenging circumstances forced me to learn how to mix faster.  That meant forcing myself to mix with some hierarchy, otherwise I would screw around with one channel for three songs and miss the big picture entirely!

I realized that without some semblance of speed that I would never be able to get a good name on gigs.  So I forced myself to prioritize mixing activities, and became willing to radically alter, or remove, inputs that did not fit the mix picture.

Finally, I got a point where I felt comfortable enough with how to start my mix to focus on the other problems of the stage or songs.  Backline bleed, bad instrument tone, bad arrangements, weak singers, the list is practically endless.

My desire from these posts is to help people speed through their version of my early steps and dive in deeply to the last stage of the mixing journey at a level of depth that will allow them to have real success with their gigs/bands/clients/company.

Lets begin!

It has become apparent that it will be well after the new year before I have time to flesh out this entire thread.  I wanted to give everyone a sense of the direction I plan on heading, so that everything retains a sense of purpose:

Part and Contents: Basic
1.  Universal Principles of Mixing
2.  Approaching the Mixing Console
3.  Line Check-Precursor to Mixing
4.  Introduction to Acoustics Related to Mixing
5.  Human Hearing and Mixing
6.  Both the Forest and the Trees
7   Keeping Your Bearings Behind the Console
8   How to "Tuck in the Corners" of Your Inputs
9.  Leave it in the Mix, or Take it Out?
10. Stage Sources-Micing and Control
11. Mixing Quiet (and Mixing Loud)
12. Post Mixing Console Etiquette

Parts and Contents: Advanced

13. Dynamics Processing-Beyond Auto Mode
14. Effective Multiple Micing
15. Ambient Effects
16. Mixing Motif-Genre, Environment, and Preparation

Beyond that, anything else will be audience generated.

Universal Principles of Mixing

1.  What is Mixing?--I believe the most basic question to ask is "what is mixing?" for any particular gig.  For a band in a small bar it may be "bring the vocal levels up to meet the backline;" for a corporate show it may be "create natural sounding speech amongst three presenters;" for an arena rock show it may "make a Vox AC30 seem ten feet tall and twenty feet wide to this audience."  All valid, clear goals that give a state of mind to build a hierarchy from.

2.  Universal Principles--Are there any universal principles in mixing audio?  Some people will argue me, I am sure, but I firmly believe that there are at least a few axioms:
A. Feedback is bad, and audiences remember it.
B. Vocals are THE most important thing in almost all reinforcement.
C. Isolation between sources will never be as high as desired.
D. Its too loud for at least person in the audience.
E. Missing a cue, resulting in silence, is far worse than any minor eq or balance error.

3. Less Universal Principles--Are there more principles that are mostly, but not always, true?  Of course:
A. Close micing rules the day.  Feedback immunity and isolation require this on most gigs.  This will result in mix compromises for some sources.
B. Proximity effect is real on most sources.  Most microphones in live sound are cardiod in nature, and therefore experience a build-up (due to their internal equalization) of mids, and low mids, when placed near sources.
C. Stage sources will contribute to the sound in house.  Only in large venues, with good instrument isolation, and in ear monitoring, does this not true.
D. Stage sources will differ tremendously in volume, timbre, and dynamics.  All of this variation contributes to the rough "live" character of the event.
E. The general public is usually very weak in being able to pick out sonic subtleties in your mixing, but will complain readily about big picture things (volume, genre, lack of PA coverage).

Now that I have exposited a few of the ground rules, as I see them, I will use part three to talk about a methodology for approaching the mix console, and starting to mix.

Approaching the Mixing Console

I hesitate to go into too much detail here, because a very large part of your approach the mixing console on a gig is dictated by the nature of the event.  I can't assume you can influence the number, or location, of the channels for the show.  If you are the opener, or at a festival, these things may be completely beyond your control.

Additionally, I bring my own prejudices into this discussion.  I am left handed, and left eye dominant, which makes me opposite of most folks in some respects.  I scan naturally from left to right, and reach for things with my left hand first.  I also tend to listen more critically when cueing with my left ear.

Mixing a gig starts well before stepping up to the mixing console.  It may start when advancing the show, and downloading the manual to an unfamiliar console.  It may start on the stage setting up, and micing, some or all of the instruments.  It may start by talking to the festival system tech or patch guy.

For me it always starts with hearing protection.  I will wear earplugs (foamies or my Sensaphonic ER15s) as much as possible.  During loading in, while on the stage setting up, during the openers, after the show loading out, while traveling/flying.  The goal is to maximize the rest I provide my ears.

I keep my earplugs clean, and occasionally  use the over the counter earwax removal medicine.  I also try to listen to a least two different songs I know well several times before the event to gauge my hearing for the day.  If I were on a tour I would try to listen to a room mix of the night before, primarily for vocal level.  I find that vocal levels are increasingly hard to judge as familiarity with the song grows.

Now that the stage is set, and I am approaching the console, its time to ask the "What is mixing?" question.  At this point I view the question as an audio version of the serenity prayer.

Good answers before I approach the console would be "make sure the teenage girls can hear the vocals on the single" or "survive on a console I have never used before" or "fight the noticeable rumble from the stage during the opener."  Unproductive answers would be "dream I was mixing on xyz instead" or "pray for better channel count/eq/routing."

The goal is to create a mindset to work successfully within the framework currently in front of me.  Remembering that a minor error in eq or level is much better than missing a cue, first word, or first beat.  I find that this helps calm me, and minimizes a very real personal battle to panic on sub-par gigs/equipment.  It also tends to make me audience centric, and minimize any disappointment in the room/system/local crew, etc.

After the "what is mixing" question its time to walk up to the board.  And here the mechanics of a methodology kick in.

What are the first four things I do when I stand at the console?
1.  Check to make sure its on and functioning, including glancing at outboard PSU and racks
2.  Plug in my heaphones
3.  Check for all relevant channel/group/main mutes.
4.  Locate the solo/cue/pfl/afl of the moment.

A functioning console, proper mutes, cue, and heaphones are crucial to a line check, which to my mind, is the predecessor to any gig whether or not there was a soundcheck.  It sets the baseline that things are functioning properly, and frees my mind to have confidence towards mixing, and not playing system tech (I default to system tech).  With a functioning console prepped for a line check, tis time to move forwards.

Part 3 talks about about what constitutes an effective, and professional, line check.  I personally don't believe it involves letting the whole audience hear you eq each individual drum over the main PA, nor hear the monitor engineers hiss and "check, check" into every mic.  

Line Check-Precursor to Mixing

Here in part three I want to discuss the mechanics of a successful line check, and then take a several section excursion into the basics of human hearing and acoustics.  I have found it extremely helpful to have a sense of how we hear, and how sound plays in the room, when it comes to learning how to use the tonal-shaping tools available.

I, like most mixers I have met, was not blessed with perfect pitch, and any frequency recognition I have gained has been with practice and repetition.  Absence from practice I have found results in loosing the ability to identify the frequency ranges of tones quickly.  Any "cheat sheets" that can be internalized help speed the ability to get in the ballpark, frequency-wise.  That will be the motivation for the next couple sections.  Now, on to a line check

A line check's primary purpose, to my mind, is to insure that all relevant signal inputs make it to the signal outputs.  Any more than this is going to take too much time, resulting in mistakes, missed channels, etc.

A line check is generally not a time to fiddle with eq, adjust attack or release times on compressors, and other such diversions.  If you can adjust such parameters quickly from memory on consistent sources, perhaps consider adjusting those parameters on one or two key channels (e.g. lead vocals).

I feel that a line check is essential, whether there was a soundcheck or not.  In the case of no soundcheck, it is an essential component of making noise come out of the pa.  In the case of a full sound check, it is a confidence booster that everything is still plugged in and working as before, and that no one has toyed with the console.  In the festival situation, the system tech/babysitter may offer to help you with this, and I suggest taking advantage of that resource.

In my methodology for a line check I try to split tasks between what requires active signal and what doesn't.  For instance, setting the gain trim of a channel requires the channel to have signal passing through it, but checking the bus routing of the channel does not require signal.  Checking whether a compressor is bypassed or not does not require signal, but checking whether the insert point and compressor are passing audio does require signal.

If there was a substantial soundcheck, simply looking at the channel input meters (or cueing the channels on boards without per channel metering) while the band/tech/presenter are warming up and plugging in is sufficient.  On most better boards, a quick scan across the channels trim is all that is required.
If the board is an analog board, i will then scan up/down the channel strips to check that inserts are turned on/off, eq is turned on/off, and that the routing (LR, groups, VCAs, etc.) is correct.  On boards with detailed VCA assignment, or digital boards, this obviously is done in a different way.  The essence is to check for signal first, then check for routing.

If one has the luxury of moving input by input across the stage, and doing a more thorough scan of the each channel while a tech/musician provides a source, then count yourself in a good situation.  I personally don't feel I can depend on this happening at line check in every situation, but it is preferable.

An aside on professionalism--if you do have the luxury of going down every input in a structured manner before the downbeat, please resist the temptation to turn this into a miniature soundcheck.  I personally feel that channels should not be routed to the mains system during a line check.  It subjects the audience to random noises, appears unprofessional to me, and generally detracts from the impact of your act's downbeat.  If you have channels that you feel can be successfully equalized in the absence of the rest of the mix instruments, simply commit those equalization settings to memory!  Any source that is truly SO independent of the mix, PA, and room (and there aren't that many) should be marked on a crib sheet and set by sight, or stored in the console memory.

I feel the time to systematically evaluate each input through the pa is at a soundcheck.  If there can be no soundcheck, then part of surviving in live audio is building a mix on the fly.  The two largest struggles for me in building mixes quickly have always been being too tweaky, and panic that I missed something before the show started.  A comprehensive line check goes a long way towards alleviating any pre-mixing panic.

A topic that could be discussed during this segment is the correct balance between levels of the trim gains, and positions of the board faders.  I will, however, hold off on that for several segments, as this is something better covered under general soundcheck and mixing.

Both of those will come after discussions on hearing and acoustics.


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