This is for absolute beginners (read: church soundguys).  If you’ve been recently asked to mix for your church because you’re the only one who’s remotely qualified, or has the time to do it, then this is for you.  I can’t teach you how to listen, but I can give you basic technical information.  Most people can discern “that sounds like crap,” and so can probably twiddle knobs until it sounds less crappy.  If you can’t hear any difference, I suggest you find someone else to do the job instead.

Okies, let’s get started.  You’ve got yourself a microphone, a mixer/sound board of some sort, an amplifier, and at least one speaker.  Simple signal theory:  microphone puts out a very small signal, speakers need a relatively big signal in order to function.  It’s the job of the mixer to “preamplify” the mic, that is, to bring the signal up to a useable level.  Then to “equalize” the signal, or change how it sounds, and then to output the signal to somewhere.  What comes out of the mixer is still relatively low in level, therefore we use an amplifier to crank it up to the level that the speaker(s) need to operate.  I suggest you read a little about audio theory if you’re already lost, terms like: amplitude, frequency, spl, preamp, and perhaps a bit about acoustics.

Beyond a technical description, it is the job of your system, whatever it consists of technically, to capture, amplify, and clearly convey a message of some sort.  This can range from thoughts or ideas, to almost pure emotion in a musical performance.  Any time the technology becomes distracting from this message or emotion, it’s not doing the job it was intended for.

I can recall quite clearly a musical performance that I was running one evening, it sticks in my mind because even I was distracted from the sound board and got caught up in the raw power of the music for a moment.  <geek speak>It didn’t matter that I had over 10db of compression on the lead vocals at that single instant (ouch!), that I had taken just a skoash out of the high mids to reduce harshness for just that sort of high point, or that I had a tap-tempo delay synced to eighth notes across the vocals, for which I was riding the aux-send with the music so that it didn’t get muddy.</geek speak>  All of these elements came together as a huge chord exploded into the air, then seemed to stop and hang there as the reverb/delay trailed off.  Everyone in the room was simultaneously experiencing the same wash of emotion, unaware of the elements that went into it, but definitely appreciative of the awesome feeling that had just happened.

It’s these kinds of moments that we sound engineers ought to strive to create.  With that in mind, we continue with a bit more technical discussion.  We want every piece of equipment to be operating right at its optimum level.  The board should be in the middle of its operating range (between the noise floor and clipping), the amplifiers, any external processors,  etc.

The first step as I said is to preamplify the signal from the microphone (or other source) to a workable level.  This step is CRITICAL!! to everything else you do with the signal, therefore I will outline it step by step.  You may have been taught to “set the fader to unity and bring up the trim until you can hear it.” WRONG WRONG WRONG… you get the point.  I’ll use a Mackie brand board as an example since they are fairly popular in the market this article is intended for.

1. Before you plug in ANYTHING, switch off your amplifiers, you won’t need those for a few minutes, also drop all your faders all the way down, you’re not putting anything out of the board yet, just listening to and observing the input on the meters.  Note»
2. Determine if your board has individual level meters (or signal LED’s) for each channel.  If so, those may be useable to set the input level.  Otherwise use the “solo” or PFL button and ensure that it is in PFL» mode.  At that point you should have a meter somewhere on the board indicating your “level set,” “pfl,” “input level,” or something to that effect, the meter should show ONLY one channel, the one you have solo-ed.  Bring the “Trim” or input level control up until the meter reads “0db” or “unity” Note»
3. Repeat this for each channel while the input is at program level, meaning have the vocalists sing, the instruments play, etc.  It will be helpful to remember that 99% of people will play or sing more loudly when the real performance comes around so leave them some headroom!
4. Now, go turn your amplifier input level ALL THE WAY DOWN!! and then go ahead and flip the power switch(es).  Again this step is only necessary for your first run through.  At this point you need some input at the board, a cd player or other non-live input (ipod?) is fine because you don’t have to worry about feedback.  Go ahead and bring your Master faders up to “unity” or 0db, whatever is about 75% up, and then bring the CD player up to the same level.  You should hear very little, if any sound, coming from your speakers at this point.

1. Sllllllllooooooooowwwwwwwwwwwwllly bring up the gain controls on each amplifier channel individually.  If you’re bi-amping» you really shouldn’t need to read this, but nevertheless bring up your low/high gains equally.  Otherwise it should be relatively easy to bring your system up to a decent listening level.  Audibly it should be about 75% of the maximum volume you’d like to hear.  SPL» The idea behind all this is that: when you have a decent level at the input, and the fader is at a ‘normal’ operating position, the board will be propperly driven, the amplifiers propperly driven, and you’ll have a decent listening level in the room.  This maximizes signal/noise ratio and helps to make your system sound its best.

My next post will get a little bit into the concepts of equalization and ‘tuning the room.’