WEBVTT - TechStuff Classic: The MOOG Story: Part Two 0:00:04.400 --> 0:00:07.760 Welcome to tech Stuff, a production from I Heart Radio. 0:00:11.760 --> 0:00:14.280 Hey there, and welcome to tech Stuff. I'm your host, 0:00:14.400 --> 0:00:17.480 Jonathan Strickland. I'm an executive producer with I Heart Radio 0:00:17.640 --> 0:00:20.759 and how that tech are you. It's time for a 0:00:20.880 --> 0:00:25.000 classic episode. It's a Friday, so let's listen to part 0:00:25.079 --> 0:00:30.280 two of the two part episodes that I did started 0:00:30.400 --> 0:00:33.639 last week. This is the Mogue Story, Part two. If 0:00:33.680 --> 0:00:37.120 you have not heard part one that published last Friday, 0:00:37.360 --> 0:00:40.120 so you should go check that out. This episode originally 0:00:40.159 --> 0:00:46.400 published back on February ten, two thousand sixteen. Enjoying filters. 0:00:46.840 --> 0:00:50.600 You probably heard about filters, right. You run this through 0:00:50.600 --> 0:00:54.040 a filter. What filters are are doing is there specifically 0:00:54.200 --> 0:00:58.120 changing the harmonic content of a signal, and it lets 0:00:58.160 --> 0:01:00.800 you narrow down the range of frequency that are allowed 0:01:00.880 --> 0:01:05.319 in any produced sound, like you can specify which harmonics 0:01:05.360 --> 0:01:07.679 are allowed to go through, which ones are not allowed 0:01:07.720 --> 0:01:11.919 to go through, and that alters the quality, the tonal 0:01:12.000 --> 0:01:14.240 quality of any sound you make. So I'm going to 0:01:14.240 --> 0:01:17.679 start talking about some particular filters, and our producer, extraordinary 0:01:17.760 --> 0:01:21.440 Knowl is going to provide us with some examples of 0:01:21.480 --> 0:01:23.240 some of the stuff we talk about. So from this 0:01:23.319 --> 0:01:26.800 point forward. Uh, Noel is really gonna have free rein 0:01:26.880 --> 0:01:30.440 to go crazy Broadway style. I encourage him highly to 0:01:30.480 --> 0:01:33.760 interrupt us as often as possible with strange noises. If 0:01:33.800 --> 0:01:36.319 he hasn't already, I expect him to do so from 0:01:36.360 --> 0:01:38.920 this point forward. As the wonderful thing about Noel not 0:01:38.959 --> 0:01:41.040 being in the room where we record, we have no 0:01:41.120 --> 0:01:43.160 way of knowing what he's going to add after this 0:01:43.240 --> 0:01:46.560 is done. But at any rate, Uh, so you can. 0:01:46.640 --> 0:01:49.160 You can change the amplitude, which obviously changes the volume, 0:01:49.240 --> 0:01:51.560 and you can change the frequency, which changes the pitch. 0:01:51.680 --> 0:01:54.600 Those are very basic, right, but beyond that you can 0:01:54.640 --> 0:01:59.440 start to really have fun with it. So filters are 0:01:59.480 --> 0:02:03.440 ways to change the timbre of the sound, even within 0:02:03.960 --> 0:02:06.320 a single note. So you can press a note with 0:02:06.360 --> 0:02:09.160 no filter, it's gonna sound one way, and then you 0:02:09.200 --> 0:02:12.400 apply a filter and press that same key to create 0:02:12.400 --> 0:02:15.120 that same note, but it's going to have a different quality. 0:02:15.440 --> 0:02:18.400 So one of the basic types of filters would be 0:02:18.440 --> 0:02:21.640 what's called a low pass filter or a high pass filter. 0:02:22.680 --> 0:02:26.160 Very simple concept. The name tells you what it lets 0:02:26.160 --> 0:02:30.320 it do. So a low pass filter and let's low 0:02:30.400 --> 0:02:35.639 frequencies pass through. It blocks high frequencies now you can 0:02:35.680 --> 0:02:40.119 define what where's your cut off, so you can say, 0:02:40.160 --> 0:02:44.760 like any frequency above this is not allowed through. Anything 0:02:44.760 --> 0:02:47.200 that's lower than that can go through. Now I'm going 0:02:47.280 --> 0:02:49.960 to ask the question I think some listeners may be wondering, 0:02:50.280 --> 0:02:53.560 Hold on a second, why would there be multiple frequencies 0:02:53.639 --> 0:02:57.000 playing when you've got a single tone playing? Shouldn't that 0:02:57.080 --> 0:03:00.640 be one frequency? If you're playing one pitched note, you 0:03:00.680 --> 0:03:03.200 could be playing one pitch note if you're if your 0:03:03.400 --> 0:03:06.560 wave is just a sign wave, right, A sign wave 0:03:06.720 --> 0:03:10.800 is a pure tone. It means it's a fundamental frequency. 0:03:10.880 --> 0:03:14.880 There's no harmonic added to it. But that's the it's 0:03:14.919 --> 0:03:19.320 only one type of waveform you can play with a synthesizer. 0:03:19.360 --> 0:03:23.240 You can actually create different types of waveforms like saw 0:03:23.320 --> 0:03:28.120 tooth waves or square waves or triangular waves, and each 0:03:28.160 --> 0:03:33.680 of those contains harmonics, harmonics being uh multiples of your 0:03:33.720 --> 0:03:37.120 fundamental frequency. Your fundamental frequency is always going to be 0:03:37.160 --> 0:03:40.520 the loudest, the one with the greatest amplitude. Right, So 0:03:41.000 --> 0:03:44.400 the note you're playing, there's a specific frequency associated with 0:03:44.400 --> 0:03:47.119 that note, its amplitude is going to be the greatest 0:03:47.360 --> 0:03:54.840 in the full sound wave. But with these other waveforms triangular, square, 0:03:55.000 --> 0:04:00.200 and saw tooth, you get multiples of that particular frequency 0:04:00.320 --> 0:04:03.800 that also show up, and those are harmonics. But if 0:04:03.800 --> 0:04:06.120 you don't want to hear any of those high harmonics, 0:04:06.160 --> 0:04:10.160 you just want that deep, nasty bass rumble. Yeah, you 0:04:10.200 --> 0:04:12.280 could do it a low pass filter. And what that 0:04:12.320 --> 0:04:14.360 does is it actually you would think it would be 0:04:14.400 --> 0:04:17.760 like a really base sound, but it really kinds makes 0:04:17.760 --> 0:04:21.480 it sound sort of muffled and dark. And then if 0:04:21.520 --> 0:04:23.440 you wanted instead to do the opposite, you could put 0:04:23.440 --> 0:04:26.520 a high pass filter. On high pass filter, obviously, the 0:04:26.640 --> 0:04:29.560 higher frequencies are allowed to pass through and it blocks 0:04:29.600 --> 0:04:32.839 the lower frequencies. Sounds kind of bright and jangle exactly 0:04:33.000 --> 0:04:36.480 much much brighter sounds. So Noel, I'm sure can give 0:04:36.560 --> 0:04:40.440 us examples of what sounds like to listen to some 0:04:40.520 --> 0:04:49.360 tones played through a low pass filter and some tones 0:04:49.480 --> 0:04:54.680 played through a high pass filter. There are a couple 0:04:54.680 --> 0:04:58.039 of others that I want to mention that also are 0:04:58.160 --> 0:05:01.240 our pass filters, but they are a little different from 0:05:01.279 --> 0:05:04.920 low and high. Uh. There's the band pass filter, which 0:05:04.960 --> 0:05:07.760 allows a group of frequencies that are between the high 0:05:07.800 --> 0:05:09.880 and low ends to pass through. So in other words, 0:05:09.920 --> 0:05:13.040 you're saying, alright, anything below this frequency. I want you 0:05:13.120 --> 0:05:15.599 to cut out anything above this frequency. I want you 0:05:15.640 --> 0:05:18.880 to cut out everything in between can pass, and that 0:05:18.920 --> 0:05:24.240 gives you a different sound or band. Reject filters which 0:05:24.720 --> 0:05:27.840 specify a specific range of frequencies that are not allowed 0:05:27.880 --> 0:05:31.440 to go through, but everything else can. So it's essentially 0:05:31.440 --> 0:05:34.720 like bouncers. Okay, here's a list of people. They absolutely 0:05:34.760 --> 0:05:37.440 are not allowed in the club. My name is always 0:05:37.440 --> 0:05:40.359 on that list all the time. At least that's what 0:05:40.440 --> 0:05:45.440 they tell me. Um, but apparently my friend, uh, Benjamin Franklin, 0:05:45.640 --> 0:05:49.159 he gets in all the time. Now, beyond those filters, 0:05:49.160 --> 0:05:51.440 you can do some other fun stuff. For one thing, 0:05:51.600 --> 0:05:54.039 you remember I said that an analog sound wave is 0:05:54.040 --> 0:05:57.640 continuous course, right, so it doesn't have a quick you know, 0:05:57.960 --> 0:06:03.560 a discreete uh you where there's a stop start. Partly 0:06:03.600 --> 0:06:07.760 because of that, cut offs like where you say, here's 0:06:07.760 --> 0:06:14.720 where I want the filter to begin, are a little hazy. 0:06:15.080 --> 0:06:18.720 So uh, when you when you have your these uh 0:06:18.800 --> 0:06:25.040 these filters, you also have a transition band. The transition 0:06:25.080 --> 0:06:29.600 band is a small band of frequencies that will still 0:06:29.640 --> 0:06:33.839 play through where you've set your cut off. So, in 0:06:33.839 --> 0:06:36.080 other words, if you say you're cut off is five 0:06:36.120 --> 0:06:39.960 thousand hurts. Anything below five thousand hurts cut that off. 0:06:41.080 --> 0:06:43.880 It's not a hard stop at that frequency. There's actually 0:06:43.880 --> 0:06:47.320 it trails a little bit, which gives kind of an 0:06:47.320 --> 0:06:51.520 interesting effect. Right, So that's really cool. But beyond that, 0:06:51.560 --> 0:06:54.279 you can start to do things like adjust a filter 0:06:54.360 --> 0:06:56.560 while you're actually playing a tone. You can do this 0:06:56.640 --> 0:06:59.000 by hooking up different modules together. I'll talk about some 0:06:59.040 --> 0:07:01.320 of the other modules in this I can. And that's 0:07:01.320 --> 0:07:09.960 where you get like, like the frequency wah, well maybe, 0:07:10.000 --> 0:07:12.840 because I mean it's the way it sounds like the pitch. 0:07:13.040 --> 0:07:16.240 The pitch remains the same, but the tone of the 0:07:17.000 --> 0:07:21.200 of the note is different. So the pitch doesn't change, 0:07:21.880 --> 0:07:25.840 but the the quality of the sound changes. Noel, I'm 0:07:25.880 --> 0:07:29.520 sure it could play for us the sound of a note, uh, 0:07:29.680 --> 0:07:33.400 where the filter is changed while the note is still playing, 0:07:33.440 --> 0:07:34.800 so that we can kind of get an idea of 0:07:34.840 --> 0:07:49.400 what that sounds like. And another thing you can do 0:07:50.240 --> 0:07:54.040 is play with resonance. Uh. And one way you can 0:07:54.040 --> 0:07:56.840 play with resonance is you take the frequencies that are 0:07:56.880 --> 0:07:59.760 close to that cut off frequency where you know you've 0:07:59.840 --> 0:08:03.920 you've set the filter boundaries, and instead of just having 0:08:03.920 --> 0:08:06.280 them play out to a speaker, you feed them back 0:08:06.360 --> 0:08:10.120 into the filter. This creates a feedback loop and I 0:08:10.120 --> 0:08:13.640 believe it's called lopeo. How many more times are we 0:08:13.680 --> 0:08:15.960 going to have that joke? All right? So it creates 0:08:15.960 --> 0:08:18.120 a feedback loop, and it also changes the timbre and 0:08:18.200 --> 0:08:21.200 volume of of the pitches that you're playing, which is 0:08:21.200 --> 0:08:26.320 really cool. Um. So that's all in just talking about filters. 0:08:26.640 --> 0:08:30.040 There are other modules that we can mention that. That's 0:08:30.120 --> 0:08:33.360 just one subset of modules. Another one is called the 0:08:33.480 --> 0:08:36.719 envelope generator. You know, there's a great scene in that 0:08:36.800 --> 0:08:39.040 documentary where I don't know if you saw this one, 0:08:39.040 --> 0:08:42.720 because I think you saw part of it where Bob 0:08:42.800 --> 0:08:47.520 Mog himself is showing off one of his machines and 0:08:47.600 --> 0:08:51.400 he sort of like rubs his hand luxuriously over the 0:08:51.520 --> 0:08:56.920 envelope while he speaks of it. Does it get uncomfortable? No? No, no, 0:08:56.960 --> 0:08:59.040 it's kind of sweet. You can tell he you know, 0:08:59.160 --> 0:09:01.559 he has he as a love for this envelope. He 0:09:01.640 --> 0:09:04.480 has a relationship with this envelope. And you might wonder, well, 0:09:04.520 --> 0:09:07.520 what the heck is this thing? Anyway? Well, it's another 0:09:07.600 --> 0:09:11.120 section of the board. Yeah, and and it's you know, 0:09:11.200 --> 0:09:14.959 as you might imagine as we're talking about these different oscillators, 0:09:14.960 --> 0:09:18.679 these different waveforms, and these different filters, it's already starting 0:09:18.679 --> 0:09:20.720 to sound pretty complicated. I mean, you've got all these 0:09:20.720 --> 0:09:23.680 different knobs and stuff to control things, and maybe you 0:09:23.760 --> 0:09:29.200 want to have various effects apply to your music, but 0:09:29.320 --> 0:09:33.760 you can't by hand constantly adjust this or employ a 0:09:33.840 --> 0:09:37.559 second person too on the fly make these changes to 0:09:37.720 --> 0:09:41.080 filters so that the notes you produce have the quality 0:09:41.120 --> 0:09:45.320 that you want. Envelopes are kind of like macros in 0:09:45.360 --> 0:09:49.040 the software world, where you make shortcuts where you hit 0:09:49.080 --> 0:09:53.360 control and a letter and suddenly it creates like a 0:09:53.600 --> 0:09:58.320 series of commands that otherwise would take you multiple mouse 0:09:58.600 --> 0:10:02.040 or key strokes to actually execute the same sort of thing, 0:10:02.120 --> 0:10:06.120 except in this case we're talking about analog circuitry UM. 0:10:06.240 --> 0:10:09.760 So envelope generators can react to an incoming signal and 0:10:09.800 --> 0:10:12.680 then send out a new signal to a different module. 0:10:13.040 --> 0:10:16.280 And so it's another if then gates. So if signal 0:10:16.679 --> 0:10:20.960 X comes into the envelope generator, then send y signal 0:10:21.120 --> 0:10:24.079 to this other module so that you get the effect 0:10:24.120 --> 0:10:27.560 you want. And one type of envelope generator, one common 0:10:27.559 --> 0:10:30.040 one is the A D S R, and that stands 0:10:30.080 --> 0:10:34.920 for attack, decay, sustain, and release, which are kind of 0:10:34.960 --> 0:10:38.360 like four phases in a note. So have you ever 0:10:38.640 --> 0:10:41.480 played with a synthesizer where you pressed down on a 0:10:41.559 --> 0:10:44.840 key and the sound kind of comes up to a 0:10:44.960 --> 0:10:47.360 level and then backs off just a little bit. Oh yeah, 0:10:47.440 --> 0:10:49.920 that's the slow attack. That's the attack. Yeah, that's the 0:10:49.920 --> 0:10:53.360 attack in decay actually, because the rise in volume is 0:10:53.360 --> 0:10:55.959 the attack when it hits its peak and starts to 0:10:56.000 --> 0:10:58.360 come back down just a bit. Like let's say that 0:10:58.400 --> 0:11:00.839 there's a scale of zero to one, you press down 0:11:00.880 --> 0:11:03.680 the key, it goes from zero up to one, then 0:11:03.720 --> 0:11:07.720 it falls back to maybe point seven. That that fall 0:11:07.800 --> 0:11:10.240 back to point seven would be the decay phase. So 0:11:10.280 --> 0:11:13.200 the attack phases going from zero to one decay than 0:11:13.440 --> 0:11:16.880 one to point seven. That part happens usually pretty quickly, right, 0:11:16.920 --> 0:11:18.760 And then you still got the key held down. As 0:11:18.760 --> 0:11:20.720 long as you have the key held down, the note 0:11:20.800 --> 0:11:24.679 is playing, that's the sustain. When you release the key, 0:11:24.800 --> 0:11:28.840 you get to the release phase, which trails the note off. 0:11:28.960 --> 0:11:31.840 And you can adjust all of these things. You can 0:11:31.880 --> 0:11:35.040 adjust it so that the attack takes longer, so that 0:11:35.440 --> 0:11:39.520 the build up to the peak and then the decay 0:11:40.240 --> 0:11:43.520 is more you know, it's it's taking kind of the 0:11:43.559 --> 0:11:46.360 scenic route, or you can make the release last a 0:11:46.400 --> 0:11:49.199 really long time so that the note trails off like 0:11:49.280 --> 0:11:52.760 you have a long, sort of sustaining note. Um. All 0:11:52.800 --> 0:11:55.720 of these are things you can adjust using this type 0:11:55.720 --> 0:11:58.800 of technology, which gives you an incredible amount of flexibility 0:11:58.880 --> 0:12:02.080 when you are tried to create a specific sound. And 0:12:02.320 --> 0:12:06.120 one of the things that I think really makes synthesizers 0:12:06.120 --> 0:12:10.480 in general, and the mogue in particular, incredibly special. It 0:12:10.480 --> 0:12:15.360 makes me wish that I were capable of playing one. UM. 0:12:15.440 --> 0:12:19.680 I only plink around on keyboards, so it's pretty pathetic. 0:12:19.760 --> 0:12:23.720 Noel is like a master Jonathan. What's the song you 0:12:23.800 --> 0:12:26.320 always play when you sit down at a piano. Everybody 0:12:26.360 --> 0:12:28.959 has that annoying thing. They do the one song they 0:12:28.960 --> 0:12:30.600 know how to play, and they sit down and they 0:12:30.640 --> 0:12:33.080 do it well. There are two songs that I tend 0:12:33.080 --> 0:12:34.960 to play. One is the theme to Raiders of the 0:12:35.000 --> 0:12:39.480 Lost Arc. I mean, that's great triumphant music and it's 0:12:39.559 --> 0:12:42.160 Nazi killing music, it is. And then the other one 0:12:42.200 --> 0:12:44.520 is Jesu joy a Man's Desiring. That's that's kind of 0:12:44.559 --> 0:12:46.640 the two that I do. But I also I've also 0:12:46.640 --> 0:12:50.280 been known to do oh de Joy. Okay, so that's 0:12:50.280 --> 0:12:54.199 a bit of the old that's right. I've been obviously 0:12:54.280 --> 0:12:57.600 the the actual Joy movement, which is from you know, 0:12:57.640 --> 0:13:00.320 a much longer symphony, the Ninth Symphony. It's only that 0:13:00.360 --> 0:13:02.600 one section that I do. I can't play the any 0:13:02.600 --> 0:13:04.520 of the rest of it, and I can't really play 0:13:04.559 --> 0:13:07.040 that one very well. It's like two finger typing. It's 0:13:07.080 --> 0:13:12.240 like that, except with keyboard. I'm sure you're an astonishing blinker. Yeah. Occasionally, 0:13:12.280 --> 0:13:15.479 you know, if I get want to get fancy, you know, chopsticks, 0:13:15.760 --> 0:13:19.320 that's where it's at. A big fan of the Jaws 0:13:19.400 --> 0:13:22.880 theme myself. Yeah, nice, nice. I've been known to to 0:13:23.000 --> 0:13:26.640 do the uh, the musical motif from Close Encounters of 0:13:26.640 --> 0:13:29.480 the third kind um, which you can play just on 0:13:29.520 --> 0:13:33.080 the black keys. We'll be back with more on the 0:13:33.160 --> 0:13:45.640 Mogue story after this quick break. There's one other thing 0:13:45.640 --> 0:13:48.200 I want to mention. A couple other things, actually. One 0:13:48.280 --> 0:13:52.360 is the low frequency oscillator low frequency office oscillators also 0:13:52.360 --> 0:13:55.880 known as lfos UH. They control other modules by sending 0:13:56.160 --> 0:13:59.680 a low frequency. It's so low that sub audio you 0:13:59.720 --> 0:14:02.240 can't you can't hear it. It's beneath it's below twenty 0:14:02.320 --> 0:14:05.959 hurts um and they send a signal to other modules 0:14:05.960 --> 0:14:08.680 to alter a sound. So this is one of the 0:14:08.679 --> 0:14:12.600 ways you can make that uh, that sort of vibrato 0:14:12.960 --> 0:14:17.000 sound in a in a sustained note is altering this 0:14:17.080 --> 0:14:20.760 by using a low frequency oscillator gives it that wave 0:14:20.840 --> 0:14:36.960 equality maybe noel can demonstrate. And then you can always 0:14:37.000 --> 0:14:39.800 use a control signal to change the frequency of another module. 0:14:39.920 --> 0:14:43.680 That's called frequency modulation or FM. By the way, all 0:14:43.720 --> 0:14:47.080 these things I'm talking about about changing frequencies of electronic signals. 0:14:47.840 --> 0:14:53.640 It doesn't just apply to synthesizers like frequency modulation oscillators, 0:14:53.760 --> 0:14:57.400 changing these things. This is all basic electronics, whether you're 0:14:57.400 --> 0:15:01.280 making a sound or doing something else. It's not just 0:15:01.440 --> 0:15:04.960 in in creating music. But where of course specifically framing 0:15:05.000 --> 0:15:08.320 it in that because the topic is the mog. Uh 0:15:08.440 --> 0:15:13.920 So these are all super cool elements that give the 0:15:13.960 --> 0:15:19.160 mogue that that quality it possesses, that really unusual sound, 0:15:19.720 --> 0:15:22.760 that that unique sound. Maybe instead of unusual, I wouldn't 0:15:22.800 --> 0:15:28.280 want to say something that would have offended mog himself. 0:15:29.440 --> 0:15:34.600 By unusual, I mean unique, not bad um And uh yeah, 0:15:34.680 --> 0:15:37.560 you can these things can get monstrously huge, like I've 0:15:37.600 --> 0:15:41.880 seen synthesizers that didn't have any keyboard attached them at all. 0:15:41.880 --> 0:15:45.040 It was just the various modules to demonstrate what the 0:15:45.080 --> 0:15:48.239 modules do. So all you had were the various modules, 0:15:48.560 --> 0:15:53.280 cables to hook physically hook the modules together and unplugging 0:15:53.280 --> 0:15:56.200 cables and turning dials. And you would have have maybe 0:15:56.200 --> 0:15:59.720 in a scilloscope to see the wave form, so you 0:15:59.720 --> 0:16:03.920 had something visual there too, but it was all just 0:16:04.440 --> 0:16:08.160 plugging and unplugging cables, patching and filters, taking filters out 0:16:08.200 --> 0:16:12.560 by directly connecting modules. You know, that's interesting because when 0:16:13.200 --> 0:16:18.520 when mog and Deutsch were originally designing the mode, the 0:16:18.760 --> 0:16:21.480 you know, the synthesizer that would maybe it was the 0:16:21.520 --> 0:16:25.200 Abomba Atron, I don't know their original model. They were 0:16:25.240 --> 0:16:28.840 talking about the idea and they were discussing whether or 0:16:28.880 --> 0:16:33.200 not it should have a keyboard. The keyboard is sort 0:16:33.240 --> 0:16:36.600 of the obvious way to control the variable of pitch. 0:16:37.520 --> 0:16:42.080 But the question is should we have gone with something else, 0:16:42.120 --> 0:16:46.720 because does the keyboard inherently suggest this is really just 0:16:47.320 --> 0:16:51.080 a different kind of piano, which modified piano. You should 0:16:51.080 --> 0:16:53.960 approach it like a piano, use it like a piano. 0:16:54.120 --> 0:16:59.280 You bring your piano playing behaviors to the machine, and 0:16:59.320 --> 0:17:01.720 they were they were torn on that because they were thinking, well, 0:17:01.760 --> 0:17:05.080 what if we didn't include the keyboard, might that help 0:17:05.240 --> 0:17:08.240 encourage people to use this to generate sounds in a 0:17:08.240 --> 0:17:10.920 way that's truly new and doesn't mimic the way we've 0:17:11.040 --> 0:17:14.280 used other instruments before. Of course, we know they did 0:17:14.400 --> 0:17:16.600 end up going with the keyboard, and that kind of 0:17:16.640 --> 0:17:18.720 makes sense because the keyboard is a very useful and 0:17:18.760 --> 0:17:21.520 intuitive way to control pitch, but especially when you get 0:17:21.520 --> 0:17:24.280 to a point where you're capable of producing more than 0:17:24.359 --> 0:17:28.520 one one tone by pressing more than one key at once, right, 0:17:28.600 --> 0:17:31.679 some early synthesizers were only capable of performing like you 0:17:31.760 --> 0:17:33.760 press one key and that's the sound you would get, 0:17:33.760 --> 0:17:36.399 but you would not be able to create harmonies with 0:17:36.480 --> 0:17:39.960 some early synthesizers where you know you were if you 0:17:40.080 --> 0:17:42.600 change from key to key, you change the pitch, but 0:17:42.680 --> 0:17:45.520 you couldn't hold down a chord and have all three 0:17:45.560 --> 0:17:49.000 notes play, and some early early synthesizers. I think that's 0:17:49.040 --> 0:17:51.360 the case with the mogudn't it. I believe so, and 0:17:51.600 --> 0:17:53.760 that that would mean that you could change out the 0:17:53.840 --> 0:17:59.040 keyboard for something like a lever. Then you pull the 0:17:59.119 --> 0:18:02.240 lever and maybe when you pull the lever in one direction, 0:18:02.280 --> 0:18:04.440 the pitch increases, and when you put push the lever 0:18:04.560 --> 0:18:06.959 the other direction, the pitch lowers. That could have been 0:18:07.000 --> 0:18:09.639 the control device or anything else. Really it didn't have 0:18:09.720 --> 0:18:14.359 to be the keyboard, but they decided ultimately to have 0:18:14.400 --> 0:18:17.800 the keyboard because again it I think you're right. I 0:18:17.840 --> 0:18:20.719 think it makes it easier to understand how to produce 0:18:20.800 --> 0:18:24.480 the sound you want to produce. It becomes less It 0:18:24.640 --> 0:18:28.159 slightly steps away from the element of performance art the 0:18:28.200 --> 0:18:30.160 way a theoreman kind of is like, you can get 0:18:30.160 --> 0:18:35.000 a really skilled thereman player to create particular sounds and 0:18:35.040 --> 0:18:38.720 even play particular pieces of music, but it is hard. 0:18:39.040 --> 0:18:41.640 It is is It is an art to learn how 0:18:41.720 --> 0:18:44.840 to do that, and even then it's very imprecise. I 0:18:44.880 --> 0:18:49.120 think they probably should have replaced the keyboard with a big, 0:18:50.080 --> 0:18:53.280 big row of holes filled with a putty like a 0:18:53.400 --> 0:18:56.399 google that you have to insert your fingers into to 0:18:56.520 --> 0:18:59.199 play the note. Starting to make me think of like 0:18:59.240 --> 0:19:01.359 some sort of comedy aation of a musical instrument, and 0:19:01.400 --> 0:19:05.240 that the tree of Death and Flash Cordon reach inside 0:19:05.240 --> 0:19:09.720 and discover the true tones of the future. Right, So, uh, 0:19:09.840 --> 0:19:11.879 let's talk about wave forms. Because we mentioned them a 0:19:11.880 --> 0:19:15.400 little bit with sign waves, square waves, triangle waves, sawtooth waves. 0:19:15.480 --> 0:19:18.000 What what the heck do all of these mean? Um? 0:19:18.040 --> 0:19:21.119 And we've already talked about what a waves period is, 0:19:21.200 --> 0:19:24.679 We've talked about frequency and amplitude and uh. For for 0:19:24.720 --> 0:19:26.879 a lot of this, I'm going to be looking at 0:19:27.000 --> 0:19:31.240 using the example of a one hundred hurts um wave 0:19:32.520 --> 0:19:35.720 or frequency rather one hundred hurts frequency, so that it 0:19:35.760 --> 0:19:39.159 makes it easy for me to use the math to 0:19:39.240 --> 0:19:41.919 describe the different wave forms, because if I go with 0:19:42.000 --> 0:19:45.440 something that's not easy, then I would have to do 0:19:45.480 --> 0:19:49.760 a whole bunch of different calculations. Of so I mentioned 0:19:49.800 --> 0:19:54.560 earlier sign waves are that pure wave? Is that fundamental frequency? Uh? 0:19:54.600 --> 0:19:56.000 This would be the same as if you were to 0:19:56.040 --> 0:19:58.640 take a tuning fork and ring it. It's going to 0:19:58.760 --> 0:20:07.600 create a true to own with no harmonics. It's a 0:20:07.680 --> 0:20:12.040 single sound. Uh. And so at one hundred hurts, you 0:20:12.080 --> 0:20:15.240 would have a wave where it's period is being repeated 0:20:15.280 --> 0:20:18.560 one hundred times every second, and that's all you would get, 0:20:19.040 --> 0:20:21.639 just that, and it would be at a steady amplitude 0:20:21.680 --> 0:20:25.960 unless you were adjusting the volume. So again, amplitude refers 0:20:26.000 --> 0:20:30.360 to how loud it is in this case for for sound. Uh. 0:20:30.400 --> 0:20:32.560 And also what's really neat is that you know, you 0:20:32.640 --> 0:20:35.719 we depict this with the the peaks and valleys on 0:20:35.760 --> 0:20:39.120 a on an X Y axis, whereas the like the 0:20:39.280 --> 0:20:42.199 x axis the horizontal axis that represents time, and the 0:20:42.280 --> 0:20:46.680 vertical axis represents the the amplitude the volume. Uh. If 0:20:46.680 --> 0:20:49.320 you were to match up two sound waves that are identical, 0:20:49.440 --> 0:20:53.560 but the peaks of one sound wave are matched with 0:20:53.600 --> 0:20:56.399 the troughs of the other sound wave perfectly, they cancel 0:20:56.440 --> 0:21:01.320 each other out. So you play these two sounds simultaneously, 0:21:02.000 --> 0:21:04.280 if they line up in that way, they cancel one 0:21:04.320 --> 0:21:06.800 another out. It's like it's like all the atoms can't 0:21:06.840 --> 0:21:10.440 move because they're pushing against each other and not actually 0:21:10.560 --> 0:21:13.119 creating the vibration required for you to hear a noise. 0:21:13.680 --> 0:21:16.639 Noise canceling headphones work on a pretty similar principle to 0:21:16.680 --> 0:21:20.639 this to some degree. So that's kind of interesting. All right, 0:21:20.680 --> 0:21:22.880 So let's talk about saw tooth waves. If you look 0:21:22.920 --> 0:21:25.600 at these, it looks like a ramp and then it's 0:21:25.800 --> 0:21:28.000 like the ramp goes up into the right and then 0:21:28.040 --> 0:21:32.000 immediately drops off like has a vertical drop, and then 0:21:32.040 --> 0:21:34.800 moves up into the right again, and that's why it's 0:21:34.840 --> 0:21:37.480 called saw tooth. It looks like the teeth of a 0:21:37.520 --> 0:21:41.520 saw blade. Um These when you play them, have a 0:21:41.560 --> 0:21:43.960 buzzing sound that's really strong and clear. So this is 0:21:44.000 --> 0:21:52.199 what a saw tooth wave sounds like. Now, those are 0:21:52.240 --> 0:21:54.800 made by combining a series of sign waves at different 0:21:54.800 --> 0:21:58.359 frequencies and volume levels. The loudest sign wave defines the 0:21:58.359 --> 0:22:01.119 frequency of the overall saw tooth wave, and that is 0:22:01.119 --> 0:22:05.280 the fundamental frequency, and the other side waves represent the harmonics, 0:22:05.280 --> 0:22:08.560 which are deally at a frequency that complements the fundamental one. 0:22:08.600 --> 0:22:12.240 So generally what we talk about are multiples of the 0:22:12.280 --> 0:22:14.560 fundamental frequency. That's why I'm going to start with a 0:22:14.720 --> 0:22:18.280 one hurts. So at a hundred hurts, your next multiple 0:22:18.640 --> 0:22:22.160 like harmonic harmonic. The first harmonic would be number two 0:22:22.240 --> 0:22:25.400 because number one is your fundamental that's one hurts. Number 0:22:25.400 --> 0:22:27.880 two would be two hundred hurts because it's the multiple 0:22:28.520 --> 0:22:31.320 that's the harmonic. Number three is three h hurts, four 0:22:31.440 --> 0:22:34.280 is four hundred hurts, so on and so forth. Multiple 0:22:34.320 --> 0:22:36.240 and harmonic number are the same thing as what I'm 0:22:36.240 --> 0:22:38.399 trying to get across. All of those are playing at 0:22:38.440 --> 0:22:42.919 the same time, but the amplitude of the harmonics is 0:22:43.000 --> 0:22:47.560 lower than the amplitude of the fundamental frequency, meaning they're quieter, right, 0:22:47.600 --> 0:22:52.160 They're not overwhelming, Otherwise you would just have noise. So uh, 0:22:52.200 --> 0:22:56.040 it drops with each step further away from the fundamental frequency, 0:22:56.359 --> 0:23:00.359 and it stretches on effectively into infinity. I Eventually it 0:23:00.359 --> 0:23:02.240 gets to a point where it's so low that it's 0:23:02.280 --> 0:23:07.200 impossible for us to understand. So yeah, while the wave 0:23:07.280 --> 0:23:10.520 effectively or the the harmonics effectively go on into infinity, 0:23:10.560 --> 0:23:14.320 eventually one you hit a frequency that humans cannot perceive 0:23:14.480 --> 0:23:20.080 and to its well, in general, humans have trouble perceiving, 0:23:20.440 --> 0:23:22.399 and it's at an amplitude that's so low that you 0:23:22.400 --> 0:23:24.119 wouldn't be able to hear it anyway. The volume is 0:23:24.119 --> 0:23:25.720 too low for you to be able to detect it. 0:23:26.080 --> 0:23:29.480 But that's the that's what gives the saw tooth wave 0:23:29.600 --> 0:23:34.560 that tonal character. Then you've got square waves, which look 0:23:34.720 --> 0:23:36.439 very square. I mean, if you were to look at 0:23:36.480 --> 0:23:39.600 they almost looked like like the the battlements you might 0:23:39.640 --> 0:23:41.840 see on the top of a castle wall or something. 0:23:42.400 --> 0:23:45.760 And uh, square waves contain harmonics like a saw tooth wave, 0:23:45.880 --> 0:23:50.480 but it only contains the odd numbered harmonics so you 0:23:50.520 --> 0:23:52.720 don't have harmonic number two. If you start with one 0:23:52.760 --> 0:23:56.480 hundred hurts, you wouldn't have two hundred hurts as a harmonic. 0:23:56.520 --> 0:23:59.480 It would be skipped. But you would have three huh 0:23:59.560 --> 0:24:02.639 and five hundred and seven hundred and nine hundred. But 0:24:02.720 --> 0:24:05.479 you skip all the even numbered harmonics. You only include 0:24:05.480 --> 0:24:09.679 the odd ones. And there's an actual formula for how 0:24:10.280 --> 0:24:13.280 quiet those harmonics are. What you do is you take 0:24:13.600 --> 0:24:19.000