 Okay, so the recording is on. Welcome to BC314, our course on media and technology. Let's take a moment just to pray and we will start. Prince, can you lead us in prayer, please? Yes, sir. Thank you dear heavenly father. Thank you in this morning, Claude. Once again, you thank Claude. As you are going to learn this subject, media and technology, help us to learn and this media and technology will help us in the ministry a lot. Thank you. And your work will be more and more growing in this man a lot. Thank you. I pray and submit all the students also first in your hand. Give us such a revelation and wisdom so that we can understand. Thank you. I submit in this time. In Jesus' name. Amen. Thank you. Thank you. Okay, so we are now in that section of the course where we are talking about digital equipment that we can use in the ministry and I'm just sharing some information to us, more from the point of view of leaders. So we're not getting into, you know, how to use the equipment. That's not the focus, but more on to get some general idea about the equipment because, you know, when you're pasting the church or leading a church or being involved in some form of Christian ministry in the Christian organization and if you have to do some of this work, people will come, you know, you will be part of these discussions about buying the equipment. Sometimes you have to rent the equipment and, you know, we do rent higher equipment for special events and things like that. And so sometimes there are problems that you need to participate in discussions to resolve or new ideas and new strategies and so on. So just so that, you know, you can have some background to make right choices, decisions and so on. So yesterday we started talking, we talked about camera and then photography and then we started talking about audio. So the plan is just to finish that today. The public address system, the PA system and audio and many times, you know, most of our work would be done, you know, either as a Sunday service or a conference or a seminar, some sort of gathering where people are in a hall or in auditorium. And so we have to use PA systems. So it's almost, you know, something that we always end up using public address systems. So it's good to have some idea and so you can have meaningful discussions with people. So let's quickly review that part from yesterday and then move forward with some new information. So yesterday we were just waiting for the screen to show. Okay. Right. So yesterday we just said, you know, the sound field is something to be taught about. So when you, you know, when you're when you're planning an event or you're having your Sunday services. Now, you just tell the people, your media people, your sound people, hey, make sure that the sound field across the auditorium is, you know, is good. So that the goal is people should be able to sit anywhere in the auditorium and they should, you know, have good sound for them. Otherwise, you know, it's a waste of their time if they're sitting in a place and we don't provide good sound. Right. So though, and it all depends on how you set up this PA system. And so the sound people should be responsible, but at least you can ask that they make sure it's good everywhere. And we also talked about sound level. This is very easy to check. You can put something on your phone and walk around the hall and you will, the auditorium, you'll know what the sound level is in different places. And typically you want to keep it around a 65 dB. Then it's optimal. It's good. But you don't want it to be too high. It'll hurt people. And sometimes it can even damage the ears. So now we're going to start talking a little bit about, you know, various parts of the PA system, the public address system. Yeah, we did this little overview yesterday in the front of house console with a mixer is and so on. But let's get into a little bit of the detail and we will finish with that. Right. So generally, when you're just to know about speakers, right, so depending on the size of your auditorium or your hall, you will need the right kind and the right number of speakers. Ultimately, it's the power they put out and how the power is, you know, distributed across the auditorium. And that that is important. So typically for small groups, you know, 100 to 100 people, small conferences, 100 or less people, lectures, you know, you'd have 50 people, things like that, about 350 to 500 watts of power. But if you're going beyond that, I mean, larger venues, more hundred, several hundred people on beyond that, the power outage or power, you know, that that comes out in warts from the speakers, you need a lot more. And that the sound people will be able to determine. But just from an arrangement perspective. There are what are referred to as the main speakers. Right. So sorry, these two big ones are main speakers. And then the ones below are called subwoofers and we'll explain that. So the ones below are subwoofers and these are the stage monitors. That means this is what gives sound back to the people who are on the stage, you know, the worship team or the preacher. So they get to hear themselves and they hear how they sound. And these provide sound for the people inside the auditorium. So, you know, typically you have the main speakers subwoofers and stage monitors. The subwoofers are, you know, really speakers that provide lower frequency sound. So they kind of fill out, they make the sound whole or complete. And as the other, the speakers, the main speakers deal with sound at different frequencies and we will explain that. So, yeah, so, so we have speakers that are based on frequency range. Right. So this, this main speaker actually within it has three, you know, typically would have three, it would have what was referred to as woofers, mid range and tweeters. They're dealing, these are speakers that deal with different frequencies and they're all packaged inside a big main box, typically that's what it is. And the subwoofers deal with the lower end of the frequencies. They're kept separate, usually kept in separate boxes. So just the different types of speakers, the subwoofers are speakers that handle the lowest frequency. And so very low sound. They are called subwoofers. Then you have woofers, which deal with the next higher level of other next lower level of frequency around 500 Hertz. Then you have mid range 200, 300 kilohertz and then you have tweeter, which deal with higher frequency. So, in an auditorium, really, you would have at least these three. You have the woofer, the mid range of the tweeter speakers, usually they're built into one box, but they're all handling different frequencies. And then you put the subwoofer, which handles lower end frequency and together they give a complete sense of sound to the people inside the auditorium. Okay. So, you know, suppose somebody comes and says, you know, pastor, our tweeters are gone, or the subwoofers are gone, or the stage monitors are gone. Then you need to understand, okay, what are they telling you? They're telling you that there's a problem, but they're using their language, you know, they're using the audio language. So somebody comes and tells you, you know, stage monitors are gone. Okay, you need to know they're saying that these monitors are not working. That means people on stage can't hear, so they don't know how they're sounding. So that's a problem for the people on stage. If they say subwoofers are gone, that means they're saying these speakers are gone, they're not working, which is okay. You can still continue. You can have the main speakers and, you know, you can still have your event. They said that the sound won't sound, you know, feel, hold some complete for the people, but it's still manageable because these main speakers, within them, they usually will handle all three ranges. The high-end frequency, the high frequency that are the tweeters, the mid-range and the woofers, which handle slightly lower range. So they're all, you know, typically built into this box. So you can still go ahead with your event, right? So when people use that language and say main speakers, woofers or subwoofers or stage monitors, you understand what they're talking about. Okay, so these are just different types of speakers built inside. Now, within the speaker itself, you have what are known as active speakers and passive speakers. Active speakers, the speaker box also has a built-in amplifier. Okay, so they're known as powered speakers. So there's an amplifier built in. The advantage with that kind of a setup is if you buy an active speaker, that means a speaker with an amplifier, you can take it out anywhere. You know, so when we have small events, you know, you just carry one of these, one of these active speakers. That means it's got a built-in amplifier, so you don't need to carry another amplifier with the speaker. It's got already built in and you can plug your device. I mean, you know, or you carry a small mixer and you can plug in multiple other, you know, mic and instruments and then go directly into the speaker. You'll be fine. So for small events, you can just, you know, move it around place to place. So that's an advantage of these active speakers. Passive speakers, you typically use them for big events. They don't have an internal amplifier. They require an external amplifier, which we will talk about. And the sound from the mixer, the signal from the mixer comes in, is amplified and then put into these passive speakers. A full-range speaker cabinet, basically it contains a woofer, a mid-range and a tweeter in one box. You know, so usually this main speaker would be a full-range. So inside this, there is a tweeter, there is a mid-range and there is a woofer. So inside this box, it's called a full-range speaker. So they built everything inside one. That's usually what you would get these days. Now, one variation, instead of having these stage monitors, nowadays, people use in-ear monitors. So you will find the worship team, all the musicians, they have, you know, earplugs and they have the earphones and headphones there. And it's connected to a wireless transmitter. And so each one has their own in-line in-ear monitor. So they are able to hear their own, their sound and they know how they are sounding and so on. So, you know, you could buy or hire these in-ear monitors if you don't want to use these stage monitors. Of course, it means that this is more, you know, you're spending more because you're buying one for every person who's going to be on stage. And also there's chance of interference because these are wireless devices. The more wireless devices, there's chance of interference and disturbance. Then about the microphones that we use, there are two kinds of microphones that you need to be aware of. One is the dynamic and one is what one is called condenser. The dynamic mics are basically used for, you know, speaking, singing, those kinds of uses for on-stage use. The condenser mics are, you know, typically used to capture quick sounds. So for example, you'll find these placed above the drum kits. They will capture the sound of the cymbals. So you'll find these condenser mics pointing down wherever the cymbals are kept. So they are designed slightly differently because they want to capture sound that are fast transients, right? So you will basically have dynamic mics for those who are speaking and singing and all of that, and then condenser mics for this. And in addition to that, there are some variations. There are unidirectional, omnidirectional. Unidirectional means they pick up sound just coming from one direction and that's typically what we would use for vocals or instruments. Omnidirectional is they pick up sound coming from all directions. You wouldn't use that for speaking or singing. You would use it, you know, maybe in a case where you're placing near a sound equipment, musical equipment as needed, so on. Okay. Or if you're capturing audience response, things like that. So typically you'll use unidirectional mics, dynamic mics for people on stage. You'll use condenser mics for drum kits and so on. There are also specialized mics available. There are, you know, a lot of small, small mics that are used for the drums. There are microphones that are specific for other types of instruments. Now this gets into a specialty area, so you don't have to worry too much about it. In the early days later, you know, later on you could think about these things, but just to be aware. There are those specialized mics for instruments as well. And of course there are wired and wireless microphones. Wireless microphones helps people to move around freely on the stage. Okay. So if you want to look at how the signal flows, you know, the sound from audio, sound is converted to an electronic or electrical signal. It comes into the mixer. And from the mixer there is an equalizer, an equalizer, or there is, you know, there are special effects that are done. There is an equalizer and there's an amplifier. Okay. Now the effects and the equalizer, they work on the sound. So the mixer brings the sound together from several different inputs, several different mics. Then the effect and the equalizer and the amplifier, they work on the sound to improve the quality of the sound. Various frequencies can be adjusted. And then amplified is boosted and then is sent out to the speakers or the monitor speakers. Now, in this diagram, you see these things are separate, you know, the sound effects, the equalizer, the amplifier. But nowadays what happens is you do get mixers that have, you know, these special effects and equalizer all built in into the mixer with some amount of amplification available also built in here. So, you know, you don't necessarily have to have all of them separate. Of course, in big events, when they want to have high quality sound, they will have a lot of these things separate so they can control things at a very fine level. But typically, you know, for an auditorium conference and you have everything in one, one mixer board. It's all built in and you can control everything, control the sound and then send the signal over to the speakers. The speakers basically convert the signal back to sound, but in a very amplified way so that a lot more people can hear. So you're getting sound, converting the signal, and then you're getting sound out. But the sound out is, you know, a transformed, amplified, worked upon quality sound compared to the sound that comes in. So that's the whole, that's what the PA system does. So if you talk about the mixer here, so the mixer mixing board basically takes in a lot of number of inputs from the mics, then it works on the volume, the tone. And you can also route it to, you know, different places where you want the sound to go, speakers or etc. And then you can, you can, you know, have fine control over the sound. Now, many of you would have seen what we have here in ABC when you were here. But, so typically a mixer board is like this, you've got your inputs coming in, and then you've got different sections, you know, and I'm not sure which one are these are. So these would maybe control the volume and some of it control the equalizers and other controls as they work on the different frequencies of the incoming sound. So you can control that. And then the sound goes out. So you have different kinds of mixers here, you can see that many, many mixers that they, a lot of these things are prebuilt into these devices. You don't need to know the details, you know, we leave them to the engineers, the people to handle, but you just know that okay, there is a mixer. If they come and tell you, problem with the mixer, you know, okay, they're talking about this, where all the inputs go and, you know, there's some something here happening. So from the mixer, or in the mixer, that's where a lot of signal processing is done. They will, you know, they will, they equalize that means they can work on the different frequencies of the sound. They can also deal with different levels of the sound and they route it differently to different parts of different speakers. So those, those are all managed there within the mixer board. Another part, of course, are the cables in the, in the whole PA system. The cables are also very important. Just, just then this is just piece of information that they are different connectors that come in. So these cables have different connectors which then connect into the mics or into the mixer boards like this. These are the connectors. And just one piece of information is typically you get what is known as a snake cable or a snake. They just call it a snake. So I remember the first time, you know, somebody came, one of the people came said, you know, Pastor, we need to buy a snake. And I was like, what is it? What is it talking about? So basically this whole thing, because you have so many cables coming in, you get them, you know, all put together nicely like this. So this is called a snake cable or just snake. And it's all your plugging in and then they go out to the mixer and wherever they need to go. So this is referred to as a snake. So typically they may say we need to buy a snake for the, you know, for our PA system. This is what they are referring to. Right. So this kind of just gives us a good overview of the PA system. So basically let me just quickly review what we need to know is about the sound field, sound levels. We need to know about, you know, what are the speakers? These are the main speakers, the monitors. These are subwoofers. And within the main speakers are smaller, you know, there's a tweeter, there's a mid range and there's the woofer. And that's all built in into a full range speaker. Sometimes instead of using stage monitors, people may use in-year monitors. That's people on the stage. You need to know about the microphones. Typically these are unidirectional microphones. And if there is a drum kit, then the drum kit will have its own condenser mic. And sometimes if, you know, there are other mics that are used with the drum kit if needed. And then, you know, there's a cable that runs all the way to the mixer. You see this picture here. So the mixer, the mixer has within it a lot of sound effects. It works on the sound. You can, and all of these are typically built in the mixer or you may, or they may be separate pieces of equipment. The one that works creates effects and equalizer and amplifier. And from there it goes to the speakers. They're the main speakers or monitors. So that's, if you have that idea, you kind of, you know, okay, this is what goes into the public address system. Now what I have not mentioned is that for very big spaces, like a very big auditorium or so on, they have what are known as line array speakers. So those are, you know, high end, they are attached usually upon the ceiling or they're stacked in some way. So the whole array of speakers, not just few, but an array and they cover, you know, they make sure that they cover the entire space with equally distributed sound so on. So sometimes if you're doing a big event, they will say like, okay, we need a speaker array. So that means there's a whole arrangement of speakers that, you know, through which sound comes into the whole big, wide auditorium or the big space that you're trying to cover. But this is typically an arrangement for reasonable sized auditorium. A few hundred people should be good. Okay. That's about all that I wanted to cover here on our public address system. Next week we will get into the video side of things. We'll talk about a lot of the camera, video cameras. Then we get into live streaming, video production, just to give you an overview of, you know, the equipment that I use there and what you just need to know. And so that when people talk to you, you understand what they are saying, all right, so that we will cover next week. Any questions, any thoughts here on this, anything that you want to know? Are you all finding this useful? This is the first time we are doing this. I just felt that the need to put all of this information together so that it can be of use to others. Because as pastor, you know, I would run into all these things and for me it was kind of a learning experience. What are they talking about? And then of course you have to make decisions. For example, you know, when you're buying a mixer and you have to think about, okay, you know, how many input channels do we need? You know, eight channels, 12 channels more. And it's always good to think about the future, you know, because you're spending money. So maybe right now you're in a small auditorium, you may use eight channels. But what if, you know, you're going to have more people singing or you're going to have more inputs coming in? Should you think ahead of time and then sort of investing in an eight channel, go to a 12 channel or bigger? So these are, you know, these are questions, but you need to, if you understand, you know, what's the use of the mixer, then you can think about it. And based on your plan for growth, you can decide. Okay, let's just invest in something bigger than what we need right now so that it gives us room for growth. And, you know, it'll be easier. And similarly, when buying a speaker, I know, you know, we had to think, hey, maybe buy a portable speaker that has a built-in amplifier. Then it's easy for us to go from, you know, when we're doing small events here and there, if you have one of these, it's good for us. You know, we just take care of it with us and place it there and, you know, plug it in and start. So if you understand that the speaker has, it's a powered speaker, it comes in with an amplifier. It's good use when you're wanting, doing a small event here and there, you can carry it and just use it. So these are, you know, some useful things to know and helpful when you have to make decisions on what to buy, so on. Okay, any questions, any thoughts? Okay, so we'll close for today. Next week we'll get into slightly different space which has to do with video, videography, video cameras, video production and live streaming. We will cover that next week. Okay. Somebody could pray with us and dismiss us, please. Would like to pray. Dave, would you pray and dismiss us? Thank you. I'm not sure. There is this mic. Okay. Maybe. Yeah. Kiran, why don't you pray and dismiss us? Anyone else? You got your own? Yes, sir. Okay. Go ahead, Prince. Thank you, Lord. Thank you. Thank you for the time that you helped us to learn whatever we listened from past lot helpers. You see in our ministry that these things are very needy, full in our life also. As we did ministry, lot helpers and I equip us, all you gospel that we can reach out to them, reach out to the people. And I give glory this time, all day I submit in your hand and this week also. Amen. Amen. Okay. Thank you, everyone. Have a good weekend. Enjoy your time in worship and prayer in your local churches. God bless you. I'll see you again next week. Thank you. Bye now. Thank you. Thank you.