Go for the red pill

I feel like I owe an apology for not posting in so long, and the most recent posts aren’t even on the topic originally intended for this site.

To be honest, I’m not sure when I will be continuing here.  My life has turned upside down since June and I don’t know what it is that God wants me to be doing at the moment.

Fortunately Mike Sessler is still going strong and I encourage everyone here wanting to learn more about the controls of a sound board to check out, “There’s a Problem in the Matrix“.

What goes in must come out (unless you press the Mute button)

If you’re following along at home, we’ve discussed how the GAIN control works to control the input level into the mixing console. When you plug in that guitar, microphone, mp3 player, etc, that signal goes into one of the many input jacks on the back of the console, gets amplified or softened by the gain control, and then goes to the EQ controls. The EQ knobs also amplify or soften the signal, but it does so only at selective frequencies. (More on this someday)

After the EQ, the signal splits and goes to a couple of different places. The most obvious is the main volume fader, the big control closest to you that slides up and down. Though there may be rare exceptions, this is generally used to control the main volume in the house speakers. At the same time, the signal is also going to anything that is marked “PFL”, which stands for “Pre-Fade Listen”. Pre-fade, as in “the signal before it is affected by the main volume fader.” These are additional outputs on the board that have their own volume control and are not affected by what volume you set on the fader. The easiest one to spot is the button labeled PFL that usually appears above each fader. Mackie and some other brands call this SOLO, but it is the same thing. Pressing this button takes the signal from that channel and sends it to the headphone/control room output of the board. Because it is pre-fade, you can listen to that channel in the headphones even if the volume is turned all the way down. The gain will still have an impact on the volume you hear on pre-fade outputs, but the main fader will not.

In addition to the PFL headphone output, there are also a number of pre-fade auxiliary (AUX) outputs on the console. The Aux controls on the mixing console are basically separate volume controls for different outputs. Your primary fader will control the house speakers. The Aux controls will control everything else from monitors and in-ears for the band to hear themselves, recording outputs, effects units, etc. There are two types of aux controls on the typical board, and they are labeled as Pre or Post, or they have a button to press to switch between the two options. The “Pre” controls are outputs that ignore the fader volume you set. The “Post” controls are post-fade, their output volume is in direct relationship to the main fader. For example, if you have your volume turned all the way down so you don’t hear anything, any monitors on pre-fade may still be making noise, the post fade outputs will be silent. As you turn up the fader and begin to hear the music in the main speakers, so too will you hear them in the post-fade monitors. The pre-fade monitors will stay at the same volume regardless.

The average mixer (in my experience) has 6 aux outputs. I’ve worked with some that only have 1, and some high-end consoles that have 16, and some digital consoles with far more. But 6 is the most common, and is likely what you will be working with at an entry level position. Typically the Aux 1 and 2 controls are pre-fade, 5 and 6 are post, and the middle controls have a button to switch between the two modes. The more expensive boards may have buttons on 1 through 4, or possibly all 6 controls. The point is, you may have a choice about when to use a pre-fade or post-fade output. There is no simple definition about which to choose. Most aux controls are used for the band to control monitors and everyone may have a different opinion on whether to be pre or post-fade.

The second most common use for auxiliaries is effects. Reverb is the most common effects unit you’ll find in the typical setup. The shortest description of a reverb unit is that it takes a singers voice and makes them sound like they are in a bathroom. Done right, this is a good thing, that’s why your own voice tends to sound better in the shower. In order for it to work, you have to send the singers voice to the unit and then have the echo effect get put back into the mix. This is where the post-fade aux works best. Turn up the aux for a given singer until you have just enough of the effect to sound good (subtle is good!), and as you turn up or down the volume on that singer, the effect will change as well. The effects processor’s output will likely have its own input on the board, or the console will have a set of controls labeled “Return” that are used to put the echo or whatever effect back into the house and/or monitor mix.

This is just an introduction to the AUX controls and the idea of pre and post fade levels. In upcoming posts I will go into more detail about mixing the monitors and useful information for making the most out of an effects processor.

How It All Pans Out

Pan is a knob you’ll find on most mixing consoles, usually the first knob right above the main volume fader. It’s function is fairly simple, it assigns that channel to go out the left or right output. Yes, that sounds a lot like the “Balance” you find on your home and car stereos, but there is a subtle difference. In fact, most boards today will have a few channels where the knob is labeled Balance (or BAL) instead of Pan. Those are the channels with stereo inputs.
When you pan an input, you are taking a single input, for example a microphone or instrument, and pushing it to either the left or right output. When you turn the balance to one direction or another, you are choosing between two different inputs, left or right from stereo inputs such as MP3 players, computers, CD players, etc.
If your mixing console doesn’t have those stereo channels and you want to run your sound system in true stereo, then you can have the same effect by using two channels, and pan your left input to the left, and the second channel with the right input to the right.

Keep in mind, the pan has no effect if you are using only a mono output where your main speakers are only connected to one output on the amp or mixer. However, even in a mono system, the balance does allow you to adjust the volume between the left and right inputs. If you turn the balance to the far right, you are muting the left input. I don’t recommend it, but if you are in a bind and need to have more channels to work with, you can plug similar instruments into the two inputs of a stereo channel and use the pan as your volume. But this will only work with mono outputs and you lose the ability to EQ the two sources individually, and can’t have separate control to the monitors (auxiliary outputs).

Look for a future post that will have some tips and application ideas regarding split track CD’s. Also, the Pan plays an important role when dealing with subgroups, which will be discussed in detail also in a future post.

Treating your speakers right

In the typical American church service, you begin with a band and have to mix a couple of songs, then you get to the “easy part” where you turn on the pastor’s microphone and take a break while he speaks. But I would argue that it is so much more important that you get the volume and EQ just right for a speaker teaching the word of God than it is during the live music part of a service. For one thing, a band has multiple voices and instruments that compliment each other and even draw attention away from mistakes. But when a person is up on stage speaking, there is just one microphone on and that is the sole focus that everyone is hearing in the audience.

The overall rule is still the same – you want to be an unnoticed and invisible part of the equation. The best way to accomplish this during the sermon is to get the volume just right so that each and every person listening feels like they are in a small room hearing the pastor or teacher speaking directly to them. If the volume is too loud, they will feel like they are in an auditorium listening to a sermon with hundreds or thousands of others. In other words, if a pastor sounds like he’s going through a sound system and attention is drawn to how loud it is, you missed that mark of excellence. You also draw more attention to the sound system (vs the content of the message) when the volume is too low, leaving people wishing they had sat more up front and they might be missing words and parts of the teaching.

When the Holy Spirit is blessing the speaker with right words to say, and you have the volume just right, then you get the positive feedback of hearing people as they exit the building saying things like, “It seemed like he was speaking directly to me.”

Likewise, it is so important to get the EQ just right for that single microphone. Otherwise members of the audience may have a stray thought or two about how the microphone sounds like it’s going over a telephone or that the speaker is utilizing a tin can. The goal is to get the EQ settings just right so that it sounds like the person is speaking to you without a microphone or sound system at all.

You know how you can give people a “blind taste test” by blindfolding a person and then giving them two samples of a drink or certain food to see which they like better or whether or not they can tell a difference between Coca Cola vs Pepsi? Imagine a blind sound test. You will know that you have the volume and EQ settings absolutely perfect if a blindfolded person can’t tell how far away the pastor is or if he is even using a microphone at all. People who close their eyes during a message should be able to imagine the speaker standing a couple feet in front of them just sharing the words on their heart to the people next to them.

It is impossible to design an auditorium or sound system that can accomplish that level of perfection for every single seat in the house. But with the right loudspeaker placement and a knowledgeable person behind the mixing console practicing at getting the volume just right, it should be possible to make yourself completely invisible to most of the members of the audience.

Some of the common obstacles against such transparency include:

• The loudspeakers being too low. When you increase the volume for the sake of the people in the rear of the auditorium, you end up making it too loud for the people in the front. Keep this in mind, especially since you will likely be controlling the volume from the rear or very back of the room. It is likely that the best volume is achieved when it sounds too quiet in the sound booth area. The higher the loudspeakers are mounted, the more similar the distance sound has to travel whether to the people seated in front or rear of the auditorium. You can also setup extra sets of speakers set farther back. In either case, you should get an experienced consultant involved when your church is deciding where to mount speakers or how many sets should be used.
• Echoes and reverberations – Sound travels relatively slow, and it does bounce off the walls and ceilings. When you hear the same sound waves coming from the speaker and again after they bounce off the rear walls or ceiling, it tends to give the speaker a “muddy” effect and can make it hard to discern individual words. In some rooms, certain frequencies may be more likely to bounce and echo than others, which may require you to compensate by cutting those frequencies on the EQ. If this is a common problem in your church, you may want to look into more sophisticated equipment such as a parametric EQ which allows you to modify a narrower range of frequencies and be less noticeable if you have to compensate for a room that reverberates too much.
• Microphone placement – The best type of microphone to have for someone teaching is an earset style, generally known as a “Countryman” microphone. It is a razor thin flesh colored microphone that hangs over a person’s ear and sits right at the corner of the speaker’s mouth. Unfortunately these are still quite expensive, so the most common type of microphone you will likely be working with is a lavalier. These are the wireless microphones you see clipped to someone’s tie or jacket a couple of inches under the speaker’s mouth. The biggest problem with lavaliers is that once you’ve found the perfect volume, the speaker will turn his head or look down at the podium which completely changes the volume in the microphone and ultimately the room. So pay attention and turn down the volume if you know the person speaking is going to be looking down to read, and you might need to increase the volume if that person turns his or her head to talk about something on the side of the stage (such as a chart or content projected on the screen). In this case, a compressor would be a useful piece of equipment that can handle such volume changes automatically.
• “Essing” – If you notice how often the words end in an “s” sound as a person is speaking, you may need to de-ess the EQ. The “S” sounds and certain other emphasized consonants, or extra hissing or static like sounds can be reduced by turning down the high or upper-mid range frequencies on the equalizer.
• Leaving the room – I’ve visited some churches where the sound person gets up and leaves the auditorium after turning on the pastor’s mic. While it may be true that the mixing console doesn’t need a baby sitter and hearing the message being taught once during the first service is enough, I recommend that you do stay during all services. You may find the message “boring” by the fifth time you’ve heard it, but if you try you may learn something that you missed the first four times. This way you can be proactive in making sure that lavalier microphone sounds its best. You can be more responsive if something goes wrong, such as a wireless microphone suddenly going dead or picking up intererence. You can be ready to prevent feedback if the pastor spontaneously decides to make his message more interactive and walks in front of the stage and into the audience, etc. The same may not be true if your church utilizes video sermons, microphones are always open to surprises and risk of feedback, prerecorded video doesn’t include too many unexpected audio changes. One final point to consider: in recent auditorium designs, the mixing console is set 2/3rds or 3/4ths of the way from the stage in the middle of the audience. When you get up to leave a few minutes after the sermon starts, you changed your status from unnoticed to noticed for the people seated behind you.

Chapter 1

In the beginning was the Word, and the Word was with God, and the Word was God.  And that Word was preached from the hilltops and in front of the temple.  A reader would shout the Word of the Lord as loud as they could, and hopefully the crowd would be able to hear him.  Over the years people have learned how to build amphitheaters and project their voice so that more and more people could hear the Good News.  Until one day someone found a way to use electricity to amplify the voice out of speakers that could enable thousands to hear at one time and even at multiple locations at once. 

Sharing the Word used to mean one person would yell really loud.  But now we have mixing consoles and microphones and amplifiers, which all help of course, but what used to be a one person operation now requires people who know how to manipulate the dozens of knobs and controls so that the reader or speaker can be heard by crowds of all sizes. 

And that’s why you’re reading this book.  You have either asked or have been asked to volunteer to be a part of the team of people it takes to share God’s Word through the use of modern audio equipment.  Or perhaps you are a builder and mistakenly thought this book, Reinforcing the Church, was about how to engineer and build the structures that people meet in every Sunday.  Sorry about that, this book isn’t for you.

And in fact, this book may also not be for you even if you were intentionally looking for a beginners guide to audio systems.  It isn’t the right job for everyone.  Running the sound board and most of the tech production volunteer jobs require a special kind of person to be able to handle it.  One challenge that makes the job geared for a particular type of person is that it requires a strong level of humility (or it will teach it if you aren’t humble already). 

Think about this: how many famous audio engineers can you name?  If you are a true Beatles fan, you may know the name of some of the people involved in their recording process.  But more than likely, you don’t know any.  That’s because it is a thankless and invisible job.  Or at least, as a good engineer you hope it is.  The only time someone thinks about the sound guy or looks back to see what’s going on in the booth is when something is horribly wrong: shrieking feedback, horrible noises, no sound, etc.  Otherwise, all the attention is up on stage and you will be invisible.

And that means that it has to be your goal to be unnoticed and invisible when you are volunteering in the audio or other production environment.  The best you can hope for is that nobody notices you are there.  If you are lucky, or in a good environment with great people, you’ll at least get some praise and gratitude from the pastor, worship team, and other staff or volunteers.

Below is a list of traits that make a good audio engineer, as well as a list of warning signs that may want to prompt you to consider looking elsewhere for volunteer opportunities:

You can be a great, invisible, and unnoticed audio engineer if:

• You love music and like having the control over how loud it is
• Your picky about how the music coming out of your stereo sounds.  You’d rather have the stereo with full Bass, Treble, and other tone controls over the basic stereo that has a “Tone” knob if that (whatever that is). 
• You are or want to be a musician
• You would rather work behind the scenes to bring glory to God than be out on stage struggling against the temptation of drawing attention to yourself.
• One of your primary spiritual gifts is that of service, or helps. 
• You don’t mind some heavy lifting every once in a while.  Speakers and other gear can weigh a lot and sometimes they need to be moved.

You may want to talk to the volunteer coordinators in your particular ministry if any of the following can apply to you:

• You get frustrated that nobody ever appreciates the hours you put in or shows gratitude for a job well done.
• You have some level of tone-deafness.  If you can’t tell whether the sound from an instrument or microphone sounds natural or not, then you may have a physical handicap that prevents you from being able to mix well.
• If you have never thought about what the Bass or Treble controls do on your stereo and have never cared what setting they are at, then you may not have the attention to detail that is required to adjust settings towards the goal of invisibility.  For some people this can be a learned skill, but I have met some who for whatever reason never quite get the whole equalizer thing and may end up creating an environment where the audience is thinking about how the microphone sounds like a telephone or whatever.  The fact that the general audience would think about the fact that there is a microphone already means that you haven’t yet achieved the goal of invisibility. 
• If you think you’ll get to hang out with or meet famous people when you run sound for them, you may find nothing but disappointment.  I once was working in production for a venue where Dave Ramsey was speaking.  The closest I got to meeting him was being able to hand the microphone to one of his staff members that then passed it along.  I have yet to ever say “Hello” to Andy Stanley and have never had the chance to hang out with any of the “celebrities” at North Point Community Church where I currently spend most of my time volunteering.  If that were my goal, the staff responsible for where I volunteer should be concerned. 

None of the above automatically disqualifies you from being a part of the audio, video, or production crew.  But it may mean you aren’t best suited for the role directly behind the mixing console itself. 

Still reading?  Great, it is my hope that you find the remaining chapters informative and educational.  If you have never worked with a mixing console before, you should be able to manage your way through turning on microphones and even mixing a band by the time you finish.  And with enough practice, you too can be an unnoticed and invisible part of your church.  Fortunately that’s not the end of the story.  I don’t doubt for a minute how much God values the giving of your time and talents to help other people hear the story of the Word made flesh.  And that’s all that matters. 

May God bless you and show you directly his gratitude for your giving heart, willingness to volunteer, and humility. 

The Questions in your Mind

As you are mixing some instruments and vocals together, there are several different questions you can keep asking to evaluate which channels need to be modified. At the typical youth event or concert, the primary question is “Is this as loud as I can get it?” Even in my own high school years I got a thrill from being in the front row or mosh pit and see how much noise I can sustain. Hearing the actual instruments or words to the song came second to thinking I’m cool because the subwoofer was disrupting my digestion.

But as I find myself mixing worship events and caring more about hearing the words and the subtleties between different instruments, the main question I try to keep my focus on is “What can I turn down?”  It’s not that I don’t want anything to be loud, I still appreciate the quantity at times (and I’m not 30 yet).  But the most common mistake when mixing is to turn channels up when something isn’t right.  For example, the band is picking up volume and it’s hard to hear the singer, so you go and turn up the microphone volume.  But then the guitar is getting lost in the background and you turn it up.  Before you know it, your volume has increased too much for the room size or possibly distorting.

So instead, try to keep things at your target volume, and when you think the vocals or a certain instrument is being lost or drowned out…ask yourself what can be turned down to fix this mix.   That way you keep your overall volume consistent, and you can highlight the quality of the mix without faking it with quantity.

As I think about it, this principle is a main focus for a lot of audio engineering aspects, not just the house mix.  I apply the same principle when trying to use the equalizer to fix the tone of a channel or mix.  When a channel doesn’t sound right and the EQ needs to be modified, I think of which frequencies can be cut and do so, only increasing on the rare exceptions when too many cuts have already happened or there really is a need for boosting just a single frequency by a small amount.

This principle is especially important when mixing monitors and even in ears.  The biggest trap you can fall into is turning up instruments or microphones when a musician asks you to.  This is especially problematic when a single monitor speaker is shared between two or more musicians.  For example, the lead singer says they need more vocal and you turn it up, then the guitarist says he needs more.  As soon as you turn the guitar up, the vocalist again says he needs more.  Neither realize that the vocal range and guitar range are close in frequency range and are literally drowning each other out, competing for which input has more dominance in the monitor.  And you become stuck with this really loud monitor that is competing with and possibly overpowering the FOH (Front of House) speakers.

With dedicated monitors or in-ears, you can evaluate which instrument or channel is most important to the musician and make sure the mix reflects that, turning down other channels until the instrument they want is at the forefront (which 99 out of 100 times is their own instrument or vocal).  With shared monitors, you will have to communicate with the musicians to work out a compromise, or try to arrange the stage so that complimentary (instead of competing) instruments are sharing the monitor feed.  When the guitarist is asking for more volume, you can tell him or her that the monitor is as loud as you can allow it and ask if other instruments can be turned down instead.  Usually the people sharing the monitor can agree to some kind of compromise.

But godliness with contentment is great GAIN

In addition to frequent mentions in the Bible, Gain is also a knob on the standard mixing console (also called Trim). You’ll also find a gain control on most amplifiers. For many guitar amplifiers, gain is the only form of volume control. But don’t let this confuse you, it is an input level and not necessarily an output. If it is your only volume knob, then yes, it directly affects the output volume. But on the standard mixing console, the gain works in relationship with the EQ and Fader to decide what the volume is for a given channel.

You need a gain control because different types of audio inputs have completely different volume levels. For example, your typical microphone produces a very weak signal and requires the gain to be turned up at least half way in order to be heard or even start to cause the meter to start registering. On the other hand, MP3 players can have a rather loud volume (depending on its volume knob) and needs to have a minimum amount of gain. (In fact, there’s usually a “Pad” button next to the gain to turn down these high level inputs even more).

There’s two ways to decide on how to set the gain level. I’m not in the position to say which is right or wrong, though I do have a preference. The audio engineer in charge at your particular ministry may have his or her own preference that you need to follow.

Option 1) Set the gain using the meters on the console. Fancier mixing consoles may have a meter above every channel so you can visually see the level of sound coming in to the channel. Other consoles require that you press the Solo or PFL button to see the input level on a meter in the center or right edge of the console. While visually monitoring the level on a channel, your goal is to get the gain high enough so that the meter is responding to more than just the first green light, but low enough so that it only peaks occasionally in the yellow. If you get into the red, the sound will distort. So make sure you test the channel at its loudest to verify that you have turned the gain down enough.

With this method, you end up with all the channels being about equal to each other. In other words, if you set the fader (the main output volume for a channel) to the same place for a microphone and guitar, they get amplified at about the same volume.

Option 2) Use the gain to set the volume you will generally have that channel at. Imagine you have two guitar players, one is playing the lead/melody parts, and the second is just doing rhythm. During the concert/worship, you’ll want the rhythm guitar to be quieter than the lead so it hides in the background and enhances the music. If you set the gain according to option 1, then you will have the fader for the lead guitar set to 80% or so, and the rhythm guitar set to about 55% output level. But you can also turn the gain down for the rhythm guitar and set the fader equal to that of the lead guitar. This way you can have both faders set to about 80%, but the balance you want between the two guitars is still there (because the gain is lower, the rhythm guitar will be quieter).

This method is particularly useful on the lower end boards that do not have a Mute option on the individual channels. When your only method of silencing a channel (instrument not in use, turning off a microphone, etc) is to turn the fader all the way down, then it is helpful to know that when you bring the channel back up, you can set it to the same volume level as every other channel, you don’t have to memorize the different output levels for different instruments.

Such a method does not provide as much benefit when you can mute the channel without losing your place (you can leave the fader up and simply tap the mute button to silence it), or when you can program scenes that automatically change volume levels based on preset mixes (odds are you won’t run into these types of consoles as a new volunteer).

As you gain experience (pun intended, sorry), you’ll likely find yourself in a balance between the two options and not necessarily strictly adhering to one method or the other. Using the LED meters is a great way to start when trying to figure out where to set the gain knob to. And as the rehearsal progresses, you can adjust the gain as you hear the differences between the instruments and their parts, or just fine tuning different singers with their own different energies.

Don’t forget: EQ also affects input level. If you get the gain set just right so it peaks in the yellow, but then turn up one of the frequency knobs, you may end up in the red after all. What’s EQ you ask? Hopefully I’ll get into that in a future post/chapter.

Feedback 101

My kids are homeschooled and meet regularly with other homeschoolers.  Recently they decided to put on a talent show and I had the opportunity to sit behind the sound board for the event.  Unfortunately I couldn’t make it to the dress rehearsal because of work conflicts, so I had to wing it when I did finally get there.  My wife was involved and warned me that one of the kids who was wearing a wireless microphone might approach another microphone during a drama, her fear being that the two microphones meeting would cause feedback. 

 That’s the inspiriation for starting off with a post on where feedback comes from, because two microphones meeting does not cause it (but two microphones can be out of phase and cause an entirely different problem…a later discussion).  Being too close or too far from the microphone doesn’t cause feedback (but it is a factor). 

Feedback is a result of an output and input crossing paths when they shouldn’t.  A microphone is an input, and a speaker is an output.  If you put the two together, you can end up with feedback.  What happens is that a sound comes out of the speaker, gets picked up by the microphone, goes out of the speaker, gets back in the microphone, and this loop happens so fast that you end up with a loud noise that gets louder and louder. 

And it isn’t just microphones that can cause this.  Sometimes guitar pickups can cause feedback.  Another source can be computers.  I use my laptop for just about everything when I’m working on the production side of an event, I record the event, play pre-show music, sometimes play video clips, etc.  Recording and playback at the same time works fine, unless I forget to mute the Line In…that’s when the audio coming in (the record feed) goes right back out the computers output, which in turn goes back into the record feed, and you get a somewhat loud constant beep.  It doesn’t sound like regular feedback because the volume is fixed at whatever the computer and record feed are set to, there are no variables of distance between speaker and microphone. 

I could write pages and pages on what to do to prevent feedback, how equipment such as compressors can intervene, and so forth.  Needless to say I will revisit this topic again.  But here’s some tips to start off with:

When a person is holding a microphone that starts to feedback, their natural response is to pull the microphone away from them, or they might think they are speaking too loudly.  But the opposite may be true, because the speaker/singer is too quiet, the sound guy turns up the volume, which makes the microphone more sensitive and possibly start a feedback loop.  If the speaker/singer can be louder, the volume on the console can be turned down, and the loop be broken.

If there is a speaker facing the microphone (monitors, or house speakers if the person is in the audience), it may be necessary to turn down those speakers to control the feedback.  For example, if a person speaking is out in the audience and walks to the left side of the room in front of the main speakers, the sound guy can turn the PAN dial (kind of like a balance, tells the channel which speaker to come out of) to the right speakers so that the left speakers are quieter, and the right speakers compensate. 

Once you become more familiar with compressors and equalizers, those will also be your best tools in preventing/controlling feedback.  For example, in certain environments you can have problem frequencies, certain tones or pitches reflect off the wall or ceiling back to a microphone sooner than others.  An EQ will allow you to turn down just those frequencies without having to turn down the whole volume.

The kids talent show went well by the way.  We didn’t have the proper microphones to amplify the drama, but the audience was small and could hear the kids fine, and fortunately I had a separate volume on the record feed so that I could turn up the mic volume on the recording without risking feedback from the main speakers. 

Your questions and suggestions are welcome, so if I wasn’t clear on anything or if you have a preference on the next topic, please feel free to comment or contact me directly (my contact info is on the about page).