R.A.V.E - Episode 2 - The 4 Disciplines of AV Series: Part 1 - What You Need to Know About Audio

This episode is the first in a 4-part series called The 4 Disciplines of AV. Part 1 is all about audio, or should I say, what you need to know about audio.

Transcript

EP 2 Audio Training- 4 Disciplines Series

Stephen: [00:00:00] So I'm sure you've heard phrases like this, that it's not what you know, it's who you know that counts or fake it until you make it. I'm sure you've heard these phrases before, but the insinuation is that knowledge is not as valuable to your success as other factors like charisma or networking with influential people.

But in my experience in the AV industry is that you can only fool people so long before your shortcomings become obvious. People are going to know you don't know how to run that board, or you don't know quite as much about how sound works as you have led on. And this is important because with the rising cost of education, it's like how do you decide on what knowledge is essential and the best places to gain it?

And I've often wrestled with this idea of formal education, like [00:01:00] university education or technical schools. There are a lot of schools now that are very specific. You can, go dive deep on how to be an audio engineer and pay a lot of money to do that, versus the informal or the self-taught route of education and.

Figuring out, which is most beneficial to pursue. And I think the answer, answer to this question is going to look different for everyone. What I can do is I can boil down, I think the essential skills and knowledge in each of the major areas of the audio visual world to what I feel are absolutely essential.

For you to be successful. I can share with you that in my case, I started out my journey in a university setting, and it was a means to an end. I was a songwriter, a musician. I wanted [00:02:00] to learn how to do audio because I didn't want to be beholden to someone else's skills. So I got into a. Formal music program at a university in my home state, and then from there was introduced into what was called the music industry program.

From there, diving into the audio production side of things. So that's how I started my educational journey. But I can say, looking back now, almost over three decades, that I cannot deny that the informal things, the self-taught things. Have become as equally important as that piece of paper up on the wall, if not sometimes more important.

So many things that I've learned, little tips and tricks of paying attention to the person, to my right and to my left, or now with the plethora of information that's out on, YouTube and [00:03:00] TikTok and Instagram, things like that. You can gain so much information that way. But here's some of the things that I think no matter which way you go, and again, my goal is not to say that one way of learning is better than the other.

I think in this case there's never been a better justification for the end justifies the means than when we start talking about. Education, formal versus informal. I feel that in my career I've been successful learning what I did in my education, my formal education, coupling that with a natural curiosity and learning things on my own, that I've cobbled those things together into this knowledge base that has helped me to grow in my career and to elevate in my career.

But I also know people who. Did no formal education in this area, and they are spectacular at [00:04:00] what they do. They are the best of the best. So if you looked at their, the. Education portion of their resume maybe it looks a little skinny, but when you look at what they know and their demonstrated knowledge out in the field they probably should be teaching at universities because of what they can do and some of those people eventually do.

So I think, again, it doesn't matter how you get the information, but here. Are some of the things that I think that you need to know to be successful in some, in the different areas of the audio visual field. So we'll just start with audio. As I look back over my career and the things that were taught to me signal flowed number one.

You got to know how signal flows. That signal generates from in, from one place a source and it flows in and [00:05:00] out, different pieces of gear, and eventually it comes out the other end through the speakers in the most symbol of format, un understanding signal flow. The number one concept I think you need to get down in the audio field.

The second thing I think, is understanding the different levels of signal that you're working with. They, we have mic level signals, we have line level signals, and we have instrument level signals. In the beginning, this really confused me. But this is an important concept to get down because this will help you to understand, how much signal is coming into your console and how much you need to adjust or to push that signal to get it to come out at a comfortable level at the other end. And so then this goes into the next knowledge point for audio [00:06:00] is game staging. So gain is the amount of input level that's coming in to a piece of gear, right?

And so if we think about, an audio system in its simplest of form is we have, let's say a person like me, now I'm talking into a microphone. That microphone is going into. A console in this case, it's my zoom recorder. And it's going to, it's going to amplify that signal for it to come out because of, 'cause a mic is literally measured in millivolts.

It, the signal could flow through lots of different things, amplifier. Lots of signal processing, eq, different things like that. In each of those stages that gain can be adjusted. So if you come to a console and let's say you have a microphone that's coming out through the PA and the client says, I just, it's just not loud enough.

But yet you've pushed your fader all the way up. [00:07:00] This is where gain staging matters is that somewhere along that audio chain, something got set too low, maybe the amplifier got set too low, so you're never going to get enough output out of that channel. So gain staging. Very important concept to master as you go along.

I think another important thing is power source, power sourcing. When you're setting up an audio system, it's very important, especially when you're going into different venues, is to know where you're getting your power. A lot of times the venues will have a place for you to connect your own your own power generator to where you can, separate out the power and make sure that it's good clean power. You don't want your you don't want to share power for your speakers and your amps with what's going on in the lighting world and the video stuff, because as those faders move out for the lights, they're cutting signal. And [00:08:00] that literally will come out on the other end through your pa.

Having good, clean power sources for every. Piece of gear in your system is important. I think the fifth thing is learning the different mic types, and so this is not like specific, brands like Sure Audio Technica or Sennheiser, but these are the types of technology. Built into the mics and how they take sound energy and reproduce it into electrical energy and how that comes out on the other end.

And so the big. Three of mic types are condenser mics. You're going to see a lot of, I'm using a condenser mic right now to record my voice. Also dynamic mics. That's another section of microphones we need to learn about. And ribbon mics. So you're going to see probably dynamic and condenser mics [00:09:00] to a greater percentage more than ribbon mics.

But ribbon mic's, arm. Quote, making a comeback in the industry. So you should know how all three of these mic types or technologies work. 'cause that dovetails into the next knowledge base is mic placement or mic choices. Choosing the right mic for the right instrument or the right voice, and then knowing how to place that mic.

If you don't know what type of technology is inside of that microphone. You don't know what that microphone's going to do, say with a snare hit or a symbol crash. So being able to choose the right mic based off the type and then that also helps you know how to place it knowing microphone pickup patterns.

So that's another part of miking. So we know the mic types. That helps us to make the right choices, I think with mic placement. So maybe part A [00:10:00] and B of the sixth part here of essential Audio Knowledge is knowing pickup patterns. So how that microphone collects sound. I. We have cardio is probably the number one mic pickup pattern.

And then you have some variations of that - hypercardiod and supercardioid we're going to, we're going to see those a lot. We have figure-eight patterns. We have omnidirectional microphones. So knowing how those mics collect sound helps us, choose the right mic for the right application and how to place that mic to get what we want out, out of that instrument and accurately reproducing that sound through the PA.

The other thing I think is essential, and I'm going to switch up what I have written down here, is how mixers work, or how consoles work. Now most mixers are studios in a box. [00:11:00] I call them when I first started out doing this, you still had lots of racks and racks of outboard gear, and then the console, spoke with those things connected together through a patch bay. Now just all those things are internal, so all your eq, your compression, your effects and all of that is just built into the board. But nevertheless, knowing how, understanding how. The a formal channel strip works, that logic is still there.

I think the best way is to get yourself in front of a, even a small, analog mixer and just read the channel from the top all the way down. Is when we, where we plug that microphone into the XLR, and then when we have our gain knob or our input level, right? That we can adjust right there with our gross gain adjustments.

And then as we come down maybe there is a pad there, maybe there is a low end roll off, it's important some times [00:12:00] to be able to do that. As you come down through that channel strip, you're going to have, at the very least maybe you've got a three band fixed EQ where you've got a high, mid and low that you can adjust.

Maybe coming on down, you've got some auxiliary sends. Maybe there's like an effects knob. Even on some of these smaller mixers now they're doing little internal effects processing. Or like one knob compression. Then maybe come on down, maybe you've got a mute button to mute the channel. And then coming on down into the last section there is your actual fader where you do your mixing.

Just understanding that electrical signal when it comes in, follows that flow and then how those signals get mixed together, all those individual channels then go horizontally and flow over to your different buses. Or your outputs, right? So the main buses are your main left and right output, but then they also can flow through the other buses on the mixer, right?

If [00:13:00] we're grouping, say all the vocals together, and then so those vocals would be mapped to that bus, and then that bus would be mapped to then go out to the main left, right output. So just understanding the AR architecture of how a mixer works. The same principles are at play in a digital mixer as are in a analog mixer.

I think the more you can get in front of an analog mixer, the more things are going to make sense to you. And then the next thing about the mixing is creating an IO plan or an input output plan. Even the simplest of. Of gigs, needs an input output plan. If you're working in a theater like ours where you know, the outputs are already pre mapped, and we're not changing that because our pa is semi-permanent and it's not going to change.

Then that part of it's already done for you, but you still need to think about your inputs. Let's say you're doing a [00:14:00] theatrical play and you've got 16 lavaliers that you've got to manage that are going to go on different performers. Maybe you've got a couple of mics that you've got to place down in the pit to pick up, acoustic instruments.

Maybe you also have, some inputs coming off. Keyboards maybe digital drums, effects processors, things like that are going to be coming at you. So it's like thinking about how are you going to lay those things out on your console? Which of those things do you think you're going to be? Wrestling with the most and grouping those together.

You don't want to lay out your console to where those 16 mics are like one through four, and then, oh, let's throw the keyboard in here on channels five and six, and then let's do four more vocals. Typically, you're going to lay things out in sections, right? So let's maybe think about, we're working with a 32 channel mixer and we got 16 channels on that first.

Digital page. We'll just, you have 16 voices. Let's put those on either one [00:15:00] through 16 or 17 through 32. And then you've got the other 16 channels to start grouping the other inputs. So creating an IO plan, I encourage people to write this down and to put it on a grid. I've I, I've borrowed some of the things that I found out on the internet.

And just personalized it to the setup for the theater in which I work. But, you can create your own in Excel or other software out there. Just something that you can, even a sheet of notebook paper or the famous cocktail napkin where you can write it out and you go, okay channels one through eight are my drums.

Kick snare high hat. And then, Tom, 1, 2, 3, whatever. Just having a plan and being organized helps you a lot. I think the next essential information that you need to understand in audio is signal processing. I think the first signal processing part I would try to master [00:16:00] is understanding how e EQ works or equalization works.

Very important. This is where we, this is where we balance out the sound, right? Because not everything that comes at us is going to be. Perfect. Not every voice sounds perfectly balanced when it comes through a microphone. Microphones have, are built with certain biases, right? This is going back into, choosing the right mic for the right for the right application.

But nevertheless, understanding how we can manipulate that sound to make it sound even and smooth and natural. Or if we don't want it to sound natural, if that's the case, how we can use EQ to manipulate that voice. I can use an example of in a production. A couple years ago in my theater, we were specifically trying to get that telephone voice.

Effect, understanding the signal processing of where in the frequency spectrum we needed to focus on to [00:17:00] narrow down those bands in the EQ to get that telephone effect. Perfect. Is, was part of our knowledge of signal processing. I think the other part is compression. Understanding what compression is and why we use it.

Compression gets used a lot, especially on voices, especially in the area for podcasts. But also we use compression in when we mix bands. We I know I do, or have done some audio churches where I've been a part of, we're compressing the singer's voices. We're compressing the.

The pastor's voice that kind of thing. Why do we use compression? What does compression do to the audio signal and why is it necessary? And then the last part of signal processing, I think is effects. And this is where we open up the Pandora's box and you just have. Everything you can imagine, chorus effects, delays reverbs things like that accentuate, the performance [00:18:00] or put a gloss or a polish on what you're doing.

To me that package of understanding signal processing, and this is whether you're doing this in a live application, I'm talking more from a live application 'cause that more suits what I'm used to, but also signal processing within a, do you know, whether you're using Reaper or Pro Tools or Audacity, anything like that, you're going to have levels of signal processing that you're going to need to understand what you're doing.

When you're manipulating those factors and what to do with them and why you're doing it. Another thing that I think is absolutely essential knowledge for being good in audio is ear training. And this just comes with time. I think if you are a musician of any skill level, it's going to help you because.

You are going to tend to have a more musical sense. And so you're going to know a little bit more intuitively what to do with [00:19:00] the sounds that are coming at you, but not necessarily, these are things that can be taught. These are things that can be learned. And excuse me, it comes with time.

Speaking of time another concept is understanding the need to delay speakers in a lot of setups and a lot of bigger applications. I used to just think, you put the PA up front, you crack it up as loud as it needs to be so the people in the back can hear it and you're done.

Certainly. In its most base form, you can get things done that way, but you're going to rip people's faces off on the front, couple of rows, and you're going to get a lot of complaints. So the more intelligent way to do this is to set up the main PA from the front of the room, right? And then to put other speakers throughout the room that amplified the sound.

But. When we're sending sound to multiple locations, if we don't get that time delay just right, we create this psychoacoustic problem and speech [00:20:00] becomes unintelligible. And so a lot of boards now will actually help you to set this. Time delay properly on your speakers. You can literally, if you've got a set of delay speakers in your room, you send them out a separate bus, and on that bus you put a time delay and if you know in feet or meters or whatever format you're using to measure, if you know the distance.

You would just say, okay, I'm setting those a hundred feet from my main pa. You would just crank the knob to a hundred feet and it'll automatically you do all the calculations for you and get that time delay right to the right milliseconds.

And by putting out delay speakers, this allows you to run the output level of your main PA a little bit lower, and it just creates a more balanced sound throughout the entire room. And again dovetailing off that understanding a little bit about room acoustics and [00:21:00] how sound waves move in the air. I think this is something I learned a good bit about through my formal education is, I took a physics of music and speech class.

And understanding how sound waves actually move throughout the frequency spectrum, that higher frequencies have shorter wavelengths and are more directional. That's why when somebody hits a symbol or. Plays a flute or something with a higher pitch. It's going to be a more directional sound. And maybe something on the lower frequency spectrum, say like a kick drum or a tom or a bass guitar or something like that is going to be a longer physical wavelength and it's going to be less directional.

That's why, if you're, yeah, in your bedroom, say at home and you had your door cracked and somebody, your brother or sister has a TV up loud and the sound's going to travel down the hallway [00:22:00] and into your room. Not all those frequencies are going to get in there. At an equal volume, those lower frequencies literally are moving air differently and they can literally bend and wrap around, the doorframe and you're going to hear the lower frequencies first.

So just understand a little bit about, room acoustics. Sound waves and how they move. This has a good bit to do with understanding like where to place your speakers in a room or, if you're in a space that has a fixed pa, why they have done some treatment to the room. Either they've put some sound clouds up in the air to help absorb some of the sound and kind of bounce back.

That sound to the audience, or maybe they put some absorbers on, parallel walls so that you don't get a pinging effect in certain frequency ranges. All of that stuff really matters. I think one of the last essential things I'll mention here, and I'll be done with the audio section of knowledge [00:23:00] is tuning a system.

And in that case is, using an RTA mic. Connected to your system that can generate some white noise through your speakers. And this is an important skill to learn how to use. There's a lot of people out there that are way better at this than I am. You can watch videos of people doing this and understand a lot of this by just picking up the skill off the internet.

But I think even just watching other professional front of house engineers and how they. Approach tuning their system. Truly, this to me is truly the mark of your upper echelon operators is, of course you can, sometimes time doesn't permit you to do things like this in every single scenario where you set up an audio system.

But when you can on the bigger applications you'll want to do this process.