WEBVTT - How Musical Instruments Work 0:00:04.400 --> 0:00:07.800 Welcome to text Stuff, a production from my Heart Radio. 0:00:12.039 --> 0:00:15.000 Hey there, and welcome to tech Stuff. I am your host, 0:00:15.160 --> 0:00:18.520 Jonathan Strickland. I'm an executive producer with I Heart Radio 0:00:18.600 --> 0:00:22.000 and I love all things tech. And in a previous 0:00:22.000 --> 0:00:25.840 episode called How Music Works the Physics, I talked a 0:00:25.880 --> 0:00:30.200 lot about the basic underlying science behind music and that 0:00:30.280 --> 0:00:35.440 included how sound works and concepts like overtones, harmonics, resonance, 0:00:35.520 --> 0:00:39.480 and more So. If you haven't heard that episode, I 0:00:39.560 --> 0:00:41.720 really recommend you check it out. It will give you 0:00:41.760 --> 0:00:45.960 the underlying principles on what I'm gonna build on today, 0:00:46.200 --> 0:00:48.720 and it's gonna give a lot more of what I'll 0:00:48.720 --> 0:00:51.880 be saying in this episode more context. However, you're like, yeah, no, 0:00:51.960 --> 0:00:54.560 I'm good, let's do this. I'll just say this. Remember 0:00:54.600 --> 0:00:58.800 that playing any note on most musical instruments produces a 0:00:58.880 --> 0:01:02.720 fundamental frequent See that's the note that we hear that's 0:01:02.760 --> 0:01:06.720 being played, as well as a series of overtone frequencies, 0:01:06.959 --> 0:01:10.360 and it's those overtones that shape the sound and give 0:01:10.360 --> 0:01:13.560 it the quality we associate with that specific instrument. We 0:01:13.600 --> 0:01:16.680 call it timber. And that's why a C note played 0:01:16.720 --> 0:01:19.319 on a flute sounds different than the same C note 0:01:19.360 --> 0:01:23.080 played on a recorder or a guitar or a xylophone. 0:01:23.520 --> 0:01:26.240 If it weren't for these overtones, the notes played on 0:01:26.280 --> 0:01:29.720 instruments would sound more similar to one another. There'd be 0:01:29.720 --> 0:01:32.960 no real point in making different instruments. But as we know, 0:01:33.280 --> 0:01:37.360 musical instruments have their own distinct qualities. Before we move 0:01:37.400 --> 0:01:40.720 on to specific groups of musical instruments, I do want 0:01:40.720 --> 0:01:43.840 to talk a tiny bit about music theory, but only 0:01:44.560 --> 0:01:49.520 a tiny bit, because one, music theory gets really complex 0:01:49.760 --> 0:01:52.960 and very specific and it requires a lot more discussion 0:01:52.960 --> 0:01:56.320 than I can cover in an episode. And two I 0:01:56.360 --> 0:01:58.600 get really lost in the weeds pretty early on with 0:01:58.720 --> 0:02:00.640 music theory. If I'm being on a I am not 0:02:00.960 --> 0:02:04.920 a musician. I've never taken courses in music theory. All 0:02:04.960 --> 0:02:06.960 the learning I've done has been on my own, and 0:02:07.160 --> 0:02:11.520 I am admittedly a novice in the field. But while 0:02:11.560 --> 0:02:14.320 I've talked about frequencies and pitches and stuff, I haven't 0:02:14.360 --> 0:02:18.600 really talked about why we have specific notes in Western music. 0:02:18.720 --> 0:02:21.520 Why do we have the notes we have. The notes 0:02:21.760 --> 0:02:27.040 in Western music are A A sharp, B, C C sharp, 0:02:27.400 --> 0:02:31.720 D D sharp, E, F F sharp, G n G sharp. 0:02:31.960 --> 0:02:35.480 Each of those represents a specific frequency, or rather I 0:02:35.520 --> 0:02:38.360 should say frequency s because you can have different octaves 0:02:38.480 --> 0:02:40.680 of the same note. Right, you can have an A 0:02:41.120 --> 0:02:43.120 and then go up an octave. You still have an A, 0:02:43.440 --> 0:02:47.760 but it's twice the frequency of your previous A. Each 0:02:47.880 --> 0:02:52.280 note in this sequence is a semi tone apart from 0:02:52.360 --> 0:02:55.519 the previous note, as well as a semi tone apart 0:02:55.600 --> 0:03:00.000 from the following note, and collectively it's called the chrome 0:03:00.040 --> 0:03:02.760 matic scale. Now I could have started on any one 0:03:02.919 --> 0:03:06.360 of those notes, and after the letter G you wrap 0:03:06.480 --> 0:03:10.240 back around to the letter A and get back to 0:03:10.360 --> 0:03:12.800 my starting point. That's still a chromatic scale, but it 0:03:12.880 --> 0:03:16.680 raises a question like why is there an A note? 0:03:17.360 --> 0:03:21.360 Why does the sequence go up to G? Why do 0:03:21.440 --> 0:03:25.160 all notes except B and E have sharp notes? What 0:03:25.320 --> 0:03:29.800 even defines a note? These pitches correspond to frequencies that 0:03:29.880 --> 0:03:34.360 Western musicians and audiences have found appealing over time, and 0:03:34.400 --> 0:03:38.040 so it kind of solidified out of what people liked. 0:03:38.720 --> 0:03:40.880 There are other music scales, by the way, such as 0:03:40.920 --> 0:03:45.160 the diatonic scale. While the chromatic scale includes the twelve 0:03:45.360 --> 0:03:49.480 semi tones found in Western music, the diatonic scale is 0:03:49.480 --> 0:03:52.560 a scale of seven notes, five whole tones, and two 0:03:52.600 --> 0:03:55.960 semi tones and do re mi fa, so lat do 0:03:56.760 --> 0:04:00.080 that little bit you've heard if you've ever listen the 0:04:00.120 --> 0:04:03.640 sound of music that represents a diatonic scale. And it 0:04:03.720 --> 0:04:07.400 gets way more complicated than all this. But to really 0:04:07.480 --> 0:04:09.680 dive into that, we'd have to go into a whole 0:04:09.760 --> 0:04:13.680 history of music and the development of music theory and philosophy, 0:04:14.280 --> 0:04:17.400 and we'd have to talk about ratios and major keys 0:04:17.520 --> 0:04:19.880 and minor keys, and honestly, it's way more than what 0:04:20.000 --> 0:04:22.599 we really need to consider for this episode. The important 0:04:22.600 --> 0:04:25.680 thing for us to note, ha ha ha, is that 0:04:26.279 --> 0:04:29.360 the pitches represented in the chromatic scale tend to be 0:04:29.440 --> 0:04:33.320 the ones that Western musical instruments are designed to replicate 0:04:33.800 --> 0:04:37.080 when they are properly tuned. So you can think of 0:04:37.279 --> 0:04:41.279 musical instruments as being a reflection of our natural kind 0:04:41.360 --> 0:04:45.600 of affinity towards these particular notes in the West. And 0:04:45.760 --> 0:04:48.920 I have to keep saying that because music, while it 0:04:49.040 --> 0:04:51.640 is a universal thing among humans that you know, we 0:04:51.839 --> 0:04:55.880 make music, it's not a universal set of laws across 0:04:56.000 --> 0:04:58.440 all cultures. All right, I got all that out the way. 0:04:58.520 --> 0:05:02.800 Let's talk about the general classifications of modern instruments, and 0:05:02.960 --> 0:05:05.279 for the purposes of this podcast. Again, I'm just talking 0:05:05.320 --> 0:05:07.560 about the typical instrument groupings that you would find in 0:05:07.640 --> 0:05:10.320 a Western orchestra. And I realized this brings a lot 0:05:10.360 --> 0:05:12.720 of cultural baggage into the discussion. But just know that 0:05:12.800 --> 0:05:15.400 the examples I give are meant to represent large groups 0:05:15.560 --> 0:05:19.400 of instruments across different cultural boundaries that share, you know, 0:05:19.520 --> 0:05:23.920 similar qualities. If after I cover all the major classifications 0:05:23.960 --> 0:05:25.800 in Western orchestras, I have a bit of extra time, 0:05:25.839 --> 0:05:28.920 we'll tackle some stuff that isn't typically part of those ensembles. 0:05:29.000 --> 0:05:31.240 There's one in particular that I know I'm going to 0:05:31.360 --> 0:05:35.200 cover that you don't typically find in an orchestra. Now, 0:05:35.279 --> 0:05:38.320 out of all the categories of those musical instruments, I 0:05:38.360 --> 0:05:41.600 would say percussion is the easiest to explain. Now, I 0:05:41.680 --> 0:05:44.560 do not mean it's the easiest to play by any means, 0:05:45.000 --> 0:05:48.640 because I think playing any musical instrument requires skill and 0:05:48.760 --> 0:05:51.480 lots of practice and dedication, especially if you want to 0:05:51.560 --> 0:05:53.600 do it well. Also, you've got to remember that my 0:05:53.760 --> 0:05:56.679 original co host and the co creator of tech Stuff, 0:05:56.960 --> 0:06:01.240 Chris Palette, is himself a talented drummer. He played professionally 0:06:01.279 --> 0:06:03.480 and stuff, and while I always like to give him 0:06:03.520 --> 0:06:05.479 a bit of the business when it comes to drumming 0:06:05.560 --> 0:06:08.080 and whether or not it counts as music. In truth, 0:06:08.120 --> 0:06:11.840 I acknowledge that being a great percussionist is really to 0:06:11.960 --> 0:06:16.240 be an accomplished musician. Percussion instruments are, of course the 0:06:16.360 --> 0:06:21.359 kind you strike or rub or otherwise you know, cause 0:06:21.440 --> 0:06:24.760 to vibrate directly, and they're probably the oldest subset of 0:06:24.920 --> 0:06:29.280 musical instruments, as it seems like we'd probably figure out 0:06:29.360 --> 0:06:31.360 pretty early on as human beings that if you hit 0:06:31.560 --> 0:06:34.960 that thing with that other thing, it makes a pretty 0:06:35.000 --> 0:06:38.880 cool sound. But this is all a guest based on intuition. 0:06:39.240 --> 0:06:43.080 We really don't know when humans first started making music, 0:06:43.640 --> 0:06:49.080 except it was definitely before last Wednesday. Percussive instruments produced vibrations, 0:06:49.320 --> 0:06:51.960 as I said, after being struck or rubbed or scraped. 0:06:52.000 --> 0:06:54.200 And there are a couple of instruments that occasionally get 0:06:54.279 --> 0:06:57.560 grouped with percussion, perhaps because it's hard to figure out 0:06:57.600 --> 0:07:01.440 where else to stick them because they aren't your traditional instruments. 0:07:02.120 --> 0:07:05.040 But I'm going to ignore those because they are the outliers. 0:07:05.120 --> 0:07:08.960 So generally you're talking about stuff like drums, xylophones, symbols, 0:07:09.080 --> 0:07:12.560 that kind of thing. There are also instruments that span 0:07:12.760 --> 0:07:17.480 percussion and other categories like stringed instruments, and the most 0:07:17.520 --> 0:07:20.280 obvious example of this type of instrument is the piano 0:07:20.680 --> 0:07:24.120 or the piano forte. Because the piano has strings, obviously, 0:07:24.240 --> 0:07:28.520 but those strings are struck rather than plucked or strummed 0:07:28.880 --> 0:07:32.120 or bode. There are little hammers inside the piano. They 0:07:32.280 --> 0:07:35.200 swing when their respective key is pressed on the keyboard, 0:07:35.600 --> 0:07:39.440 and the hammer strikes its respective string, which then vibrates 0:07:39.760 --> 0:07:43.720 at its fundamental frequency. And that's determined by a lot 0:07:43.760 --> 0:07:46.240 of stuff, including the length of the string, what the 0:07:46.280 --> 0:07:48.400 string is made of, the thickness of the string, and 0:07:48.440 --> 0:07:51.280 how much tension is on it. But a standard piano 0:07:51.360 --> 0:07:55.640 has a D eight keys, some have more, many have fewer, 0:07:56.200 --> 0:07:58.040 but that means they also if they have a D 0:07:58.120 --> 0:08:00.600 eight keys, they have a D eight strings and usually 0:08:00.680 --> 0:08:05.000 eighty eight hammers. Will transition over to stringed instruments in 0:08:05.040 --> 0:08:08.760 a second since we're on the subject, but really, percussion 0:08:08.880 --> 0:08:10.680 is is one of the simplest ones for me to 0:08:10.760 --> 0:08:13.760 explain from a physics perspective. The only other thing I 0:08:13.880 --> 0:08:16.640 might mention is that some percussion instruments are said to 0:08:16.720 --> 0:08:20.560 be pitched, meaning they can produce musical notes of one 0:08:20.720 --> 0:08:24.360 or more pitches, and some are considered unpitched, meaning they 0:08:24.480 --> 0:08:28.360 produce a sound of indefinite pitch. So a xylophone is 0:08:28.440 --> 0:08:32.280 a pitched percussion instrument, as each wooden bar produces a 0:08:32.360 --> 0:08:35.439 different pitch when you strike it with a hammer. Symbols 0:08:35.640 --> 0:08:39.120 or shakers or bass drums and similar instruments are said 0:08:39.160 --> 0:08:42.000 to be unpitched, and this is a good time to 0:08:42.080 --> 0:08:46.560 talk about why some sounds are considered unpitched. Some sounds 0:08:46.600 --> 0:08:50.959 consist of numerous frequencies at similar levels of amplitude, and 0:08:51.080 --> 0:08:53.840 amplitude is volume. You know. Remember in the previous episode 0:08:53.840 --> 0:08:56.960 I was talking about overtones and how most musical instruments 0:08:57.000 --> 0:09:01.120 produce not just a fundamental frequency, but several other frequencies, 0:09:01.360 --> 0:09:04.920 and those other frequencies are typically at much lower amplitudes 0:09:05.040 --> 0:09:08.160 than the fundamental, so we don't hear them as distinct pitches. 0:09:08.720 --> 0:09:12.200 But some instruments produce multiple frequencies of sound at near 0:09:12.320 --> 0:09:16.320 equal amplitudes, and we get this weird combination effect. Audio 0:09:16.440 --> 0:09:20.280 engineers will talk about the color of noise, and you've 0:09:20.360 --> 0:09:23.760 likely encountered examples of this, such as white noise or 0:09:23.960 --> 0:09:28.160 pink noise. White Noise is any collection of equally spaced 0:09:28.320 --> 0:09:32.040 frequencies of sound within a specific bandwidth, all at the 0:09:32.160 --> 0:09:36.360 same amplitude. So the high frequencies and the low frequencies 0:09:36.640 --> 0:09:39.640 all are at the same volume, and you get that 0:09:39.840 --> 0:09:42.200 white noise. This is going to come back to play 0:09:42.360 --> 0:09:46.440 a little bit later. The other colors of noise describe 0:09:46.720 --> 0:09:51.720 distributions of amplitude that either increase or decrease with bands 0:09:51.800 --> 0:09:55.480 of frequencies, so that you get louder high frequencies than 0:09:55.679 --> 0:09:59.000 low frequencies. That's pink noise, or you get the opposite, 0:09:59.040 --> 0:10:02.679 you know, higher low frequencies than than the high frequencies 0:10:02.720 --> 0:10:07.480 that would be blue noise. So unpitched percussion instruments produce 0:10:07.679 --> 0:10:10.840 sounds that are closer to noise. Not that this means 0:10:10.920 --> 0:10:13.960 they are unpleasant, but rather the frequencies of sound they 0:10:14.040 --> 0:10:16.800 produce are such that we do not perceive a specific 0:10:16.920 --> 0:10:20.160 note or pitch with them. Now that we've got the bing, 0:10:20.280 --> 0:10:22.920 bang boom stuff out of the way, let's talk about 0:10:22.960 --> 0:10:26.440 instruments that use either strings or air to create sound. 0:10:26.720 --> 0:10:29.560 And if we peek at the physics behind these instruments, 0:10:29.880 --> 0:10:31.880 we're going to see that they rely on the same 0:10:32.120 --> 0:10:37.440 underlying thing, which are called standing waves. So what is that, Well, 0:10:37.679 --> 0:10:41.199 there are different kinds of waves. You've got traveling waves, 0:10:41.520 --> 0:10:43.599 So these are waves that start at one point and 0:10:43.679 --> 0:10:47.319 then they travel down through whatever medium they're going through. 0:10:47.720 --> 0:10:49.400 If you had a way of seeing the wave, you 0:10:49.440 --> 0:10:51.839 would actually watch as it started at a point of 0:10:51.880 --> 0:10:54.240 origin and move all the way through its medium. You 0:10:54.280 --> 0:10:57.000 could follow it from start to finish. Standing waves are 0:10:57.000 --> 0:11:00.280 a bit different. This is another tough concept to get 0:11:00.320 --> 0:11:03.640 across without visual aids. But imagine you've got a slinky 0:11:03.840 --> 0:11:06.319 and you've attached one into the wall, so you've you 0:11:06.480 --> 0:11:08.680 glued one end of a slinky to wall. Don't actually 0:11:08.960 --> 0:11:11.559 do this, and then you stand far enough back where 0:11:11.600 --> 0:11:16.079 you've stretched the slinky out from the wall to you 0:11:16.360 --> 0:11:18.760 so it's nice and tight, and you send a quick 0:11:18.880 --> 0:11:21.839 pulse by moving the slinky up and then down, and 0:11:22.040 --> 0:11:23.959 you just whip it down the length. You would be 0:11:24.000 --> 0:11:25.880 able to watch that go all the way to the wall. 0:11:26.520 --> 0:11:29.480 It would hit the wall, and then this pulse would 0:11:29.520 --> 0:11:33.040 reflect off the wall. But because that that side of 0:11:33.080 --> 0:11:37.280 the slinky is actually anchored to an unmoving point, uh, 0:11:37.480 --> 0:11:41.079 then that reflection will get inverted. The pulse will be 0:11:41.160 --> 0:11:43.200 as if it were a down then up as opposed 0:11:43.200 --> 0:11:46.000 to an up then down, and it will come back 0:11:46.280 --> 0:11:49.719 the length of the slinky. Now, let's say just as 0:11:49.840 --> 0:11:53.160 the wave is reflecting, you introduce a second pulse down 0:11:53.240 --> 0:11:56.480 the length of the slinky in the original orientation of 0:11:56.520 --> 0:11:59.439 the first pulse, So you're going up and then down. Now, 0:11:59.679 --> 0:12:02.920 that mean that these two pulses, as they're traveling toward 0:12:03.040 --> 0:12:06.480 one another, are inverted with respect to each other, and 0:12:06.720 --> 0:12:10.319 once they pass through the center point, they undergo what's 0:12:10.400 --> 0:12:14.600 called destructive interference. In the very middle of the slinky, 0:12:15.200 --> 0:12:17.880 you would have no movement. It would be equilibrium, and 0:12:18.400 --> 0:12:20.920 the two pulses would pass through and continue on for 0:12:21.000 --> 0:12:23.120 the rest of the length of the slinky, But that 0:12:23.360 --> 0:12:27.720 little middle point, which we would call a node, wouldn't move. 0:12:28.280 --> 0:12:31.480 So the points in a standing wave that maintain equilibrium 0:12:31.800 --> 0:12:35.559 that do not oscillate are the nodes. The oscillating points 0:12:35.640 --> 0:12:40.120 with the greatest amplitude or deviation from the equilibrium are 0:12:40.200 --> 0:12:43.240 called anti noodes. And you can actually see this on 0:12:43.320 --> 0:12:45.240 the string of a guitar. If you were to strum 0:12:45.760 --> 0:12:48.440 a guitar string and slow things down, you'd see all 0:12:48.480 --> 0:12:52.559 the points along the string that are still relative to 0:12:52.640 --> 0:12:54.760 the links on either side. They're going up and down, 0:12:54.840 --> 0:12:57.000 like if you were doing this super slow motion with 0:12:57.080 --> 0:12:58.880 a strobe light effect, you would really be able to 0:12:58.920 --> 0:13:01.559 see it, and it's kind of trippy. And that is 0:13:01.600 --> 0:13:04.120 a standing wave. The wave does not appear to move. 0:13:04.240 --> 0:13:07.840 You see the peaks and troughs going up and down, 0:13:08.520 --> 0:13:11.640 but you have these fixed points, these nodes that are 0:13:11.720 --> 0:13:14.599 not moving, and so the wave doesn't seem to be 0:13:15.000 --> 0:13:17.720 moving down the length of the medium. It just seems 0:13:17.760 --> 0:13:20.800 to be this up and down oscillation on either side 0:13:20.840 --> 0:13:25.480 of these anchored nodes. So that's a standing wave. And 0:13:25.640 --> 0:13:29.000 wind instruments do this just like stringed instruments do, except 0:13:29.120 --> 0:13:32.480 in wind instruments we're talking about the movement of a 0:13:33.040 --> 0:13:36.320 column of air that's the medium, as opposed to a string. 0:13:36.440 --> 0:13:38.760 So instead of a physical string between two anchor points, 0:13:39.160 --> 0:13:41.640 we're talking about a column of air inside an instrument, 0:13:41.840 --> 0:13:43.160 and we're going to get back to that a little 0:13:43.200 --> 0:13:46.240 bit later in this episode. Alright, so let's get to 0:13:46.400 --> 0:13:52.520 those stringed instruments. Producing notes on stringed instruments involves plucking, strumming, bowing, 0:13:52.679 --> 0:13:56.640 or otherwise causing strings to vibrate, which produces the corresponding 0:13:56.679 --> 0:13:59.520 sound of the musical instrument. The sound produced, as I 0:13:59.640 --> 0:14:02.600 mentioned with the piano, depends upon the length of string, 0:14:03.600 --> 0:14:06.160 what the string is made of, how thick or stiff 0:14:06.280 --> 0:14:09.959 the string is, and the amount of tension on that string, 0:14:10.320 --> 0:14:13.600 Plus the overall design of the musical instrument matters as well, 0:14:13.840 --> 0:14:16.800 such as whether or not the instrument has a resonance chamber. Okay, 0:14:16.880 --> 0:14:20.600 so some general rules. Let's say that you've got two strings. 0:14:21.040 --> 0:14:23.440 They're made out of the exact same material, they have 0:14:23.600 --> 0:14:26.480 the same thickness, they are under the same amount of tension, 0:14:27.000 --> 0:14:30.000 but one is longer than the other one. The longer 0:14:30.200 --> 0:14:32.880 of those two strings will produce the lower note when 0:14:32.960 --> 0:14:35.840 you strum them. But if you have two strings that 0:14:35.920 --> 0:14:38.920 are of the same material, they're the same thickness and 0:14:39.120 --> 0:14:42.880 they're the same length, whichever one has more tension on 0:14:43.040 --> 0:14:45.880 it will produce a higher note. It will vibrate at 0:14:45.920 --> 0:14:50.560 a higher frequency, So the tighter string will vibrate faster 0:14:50.920 --> 0:14:53.880 than a looser string. If you have two strings that 0:14:53.920 --> 0:14:56.400 are made of the same stuff, they're the same length, 0:14:56.680 --> 0:14:59.600 they're at the same tension, but they are a different 0:14:59.720 --> 0:15:01.920 thick nous, you've got one that's thicker than the other. 0:15:02.360 --> 0:15:04.920 The thicker string will produce a lower note than the 0:15:05.080 --> 0:15:07.720 thinner string. It will vibrate more slowly. You've got more 0:15:07.880 --> 0:15:11.600 mass there. So on an instrument like a guitar, you 0:15:11.680 --> 0:15:14.440 can have all the strings be the same length right there, 0:15:14.480 --> 0:15:17.520 the same length from nut to bridge, right the top 0:15:17.600 --> 0:15:19.560 of the neck, all the way down to the base 0:15:19.680 --> 0:15:24.080 of the strings. They're all the same, they aren't stopping 0:15:24.160 --> 0:15:27.360 at different points. So on an instrument like a guitar, 0:15:27.880 --> 0:15:29.880 you can have all the strings be the same length 0:15:30.080 --> 0:15:32.840 from the top of the neck down to the very 0:15:32.920 --> 0:15:36.200 base of the strings. All those strings are the same length. 0:15:36.680 --> 0:15:39.800 They stretch the entirety of the fretboard, but each of 0:15:39.840 --> 0:15:44.040 those strings are of a different thickness and a different tension. 0:15:44.560 --> 0:15:47.520 To have each one tuned to a specific frequency a 0:15:47.680 --> 0:15:52.440 vibration that represents a specific note. Tuning a guitar consists 0:15:52.680 --> 0:15:56.000 of adjusting the tension on those strings. So the tuning 0:15:56.080 --> 0:15:59.600 pegs are all about either increasing the tension by turning 0:15:59.600 --> 0:16:02.560 the tuning peg to tighten the string, or decreasing the 0:16:02.640 --> 0:16:05.440 tension by turning the peg the other direction to loosen 0:16:05.520 --> 0:16:08.440 the string. And strings get out of tune over time. 0:16:08.520 --> 0:16:11.800 They may stretch because of the fact that it's a 0:16:12.280 --> 0:16:15.440 you know, elastic material like the nylon strings you might 0:16:15.520 --> 0:16:19.120 find on the ukulele, or it could be environmental factors 0:16:19.240 --> 0:16:22.160 like the temperature or humidity. Those can all affect them. 0:16:22.680 --> 0:16:24.400 When we come back, I've got more to say about 0:16:24.400 --> 0:16:26.520 stringed instruments and how they work, but before we get 0:16:26.560 --> 0:16:36.600 to that, let's take a quick break. There are several 0:16:36.920 --> 0:16:40.720 stringed instruments that have a single fixed string dedicated to 0:16:41.080 --> 0:16:44.840 each note within the instruments range. So a piano is 0:16:44.840 --> 0:16:47.280 a great example. You've got your standard eighty eight notes 0:16:47.320 --> 0:16:50.880 on a typical grand piano. Harps also fall into that 0:16:51.000 --> 0:16:55.400 general category. There are some bode liars that can work 0:16:55.400 --> 0:16:58.600 a little differently, but most harps are the same way, 0:16:58.640 --> 0:17:01.320 where every string is dedicated to a specific note. So 0:17:01.480 --> 0:17:04.760 musicians who play these instruments have to manage way more strings, 0:17:05.160 --> 0:17:07.159 but they don't have to make any big changes to 0:17:07.240 --> 0:17:09.640 those strings. They don't have to alter the strings length 0:17:09.920 --> 0:17:12.440 to produce different notes. They just plug a different string. 0:17:12.800 --> 0:17:16.879 But other stringed instruments like the guitar family, or violins 0:17:17.000 --> 0:17:20.639 or cellos, viola's stuff like that, they require players to 0:17:20.800 --> 0:17:23.960 change the length of the strings by pressing down on 0:17:24.200 --> 0:17:27.600 the neck of the instrument, you know, pinching the string 0:17:28.200 --> 0:17:31.600 and thus changing the anchor points for that string. Changing 0:17:31.640 --> 0:17:34.800 the length of the string changes the strings vibration frequency, 0:17:35.200 --> 0:17:38.840 thus changing the pitch. Guitars have a fretboard, with the 0:17:38.920 --> 0:17:42.920 frets providing that anchor point for the string at specific intervals. 0:17:43.000 --> 0:17:45.480 Makes it really easy. The frets are space such that 0:17:45.640 --> 0:17:48.400 playing an open string and then playing each fret moving 0:17:48.440 --> 0:17:51.199 up the neck toward the body will follow the chromatic scale. 0:17:51.760 --> 0:17:54.560 Each fret is a semi tone apart from the one 0:17:54.640 --> 0:17:57.720 before and the one after it. I can actually demonstrate this. 0:17:58.280 --> 0:18:02.920 I am going to uh play up the scale on 0:18:03.160 --> 0:18:06.240 the G note of my cigar box guitar. So this 0:18:06.400 --> 0:18:10.600 is the open string and the first fret would be 0:18:10.640 --> 0:18:14.000 a half tone or a semi tone up, and then 0:18:14.040 --> 0:18:21.919 the next one and next m Yeah. So just by 0:18:22.000 --> 0:18:25.160 altering the length of the string you have changed how 0:18:25.280 --> 0:18:29.359 frequently it will vibrate and us increase the pitch. If 0:18:29.400 --> 0:18:31.640 you ever ever see anyone doing air guitar and they're 0:18:31.680 --> 0:18:35.720 moving their hand back when the guitar pitch is going up, 0:18:36.280 --> 0:18:40.560 they're doing it wrong. Pianos are similar to guitars in 0:18:40.640 --> 0:18:44.400 the sense that if you play twelve consecutive keys, including 0:18:44.480 --> 0:18:47.520 both the white and the black keys, you play the 0:18:47.600 --> 0:18:51.760 chromatic scale. Each key in sequence is one semi tone 0:18:51.840 --> 0:18:54.399 apart from the one before it and the one that 0:18:54.520 --> 0:18:59.200 comes after it. Bode String instruments like the violin are 0:18:59.520 --> 0:19:03.399 different from instruments like guitars in several important ways. The 0:19:03.560 --> 0:19:07.440 musician plays the instrument by drawing a bow strung with horsehair, 0:19:07.800 --> 0:19:10.959 typically with a coating of rosin on it to increase friction, 0:19:11.640 --> 0:19:15.320 and they draw this horsehair against one or more strings 0:19:15.600 --> 0:19:19.000 on the instrument like a violin violence. By the way, 0:19:19.000 --> 0:19:22.480 you have four strings, a standard guitar has six, and 0:19:22.960 --> 0:19:25.760 when you do this, when you draw the horsehair against 0:19:25.800 --> 0:19:29.480 the string, it causes that string to vibrate. Unlike a guitar, 0:19:30.080 --> 0:19:33.880 the violin and instruments like it don't have a fretboard. 0:19:34.240 --> 0:19:36.240 They have what are called fingerboards, but there are no 0:19:36.400 --> 0:19:39.600 frets on them. Musicians can still change the length of 0:19:39.680 --> 0:19:42.720 strings by pressing down on them, similar to a guitarist, 0:19:43.200 --> 0:19:46.600 but without the frets. It involves learning the relative positions 0:19:46.640 --> 0:19:48.960 of where your fingers need to go on that fingerboard 0:19:49.280 --> 0:19:51.439 and requires a lot of muscle memories that you can, 0:19:51.840 --> 0:19:56.919 you know, replicate notes accurately, wind bode the strings. Vibrations 0:19:57.000 --> 0:19:59.960 transferred to the body of the violin through the bridge 0:20:00.400 --> 0:20:03.280 that's the part at the base of the strings, and 0:20:03.600 --> 0:20:06.520 it goes down into the body of the violin through 0:20:06.600 --> 0:20:09.600 what is called the sound post, which is in the 0:20:09.720 --> 0:20:14.200 resonance chamber. The sound boast is both to transmit vibrations 0:20:14.320 --> 0:20:16.680 from the top of the violin to the the back 0:20:16.760 --> 0:20:19.840 of the violin and make the whole body vibrate and resonate, 0:20:20.160 --> 0:20:23.080 but it's also meant to support the top of the violin. 0:20:23.119 --> 0:20:25.080 There's a lot of pressure on the top of a 0:20:25.200 --> 0:20:29.280 violin because of the tension that's on those strings. The 0:20:29.440 --> 0:20:32.480 sound emerges from holes that are in the top of 0:20:32.600 --> 0:20:36.040 the violin's face. These are called f holes, and the 0:20:36.119 --> 0:20:40.120 resonating body amplifies the sound of the strings significantly. Many 0:20:40.200 --> 0:20:45.000 stringed instruments have resonance chambers which helps amplify and direct sound. 0:20:45.080 --> 0:20:47.560 In fact, the cigar box guitar I was just playing 0:20:47.960 --> 0:20:51.840 has a resonance chamber. That's the box, the actual cigar box, 0:20:52.119 --> 0:20:55.760 and the The luthier who made my cigar box guitar 0:20:56.200 --> 0:20:59.159 has cut a hole in that box so that the 0:20:59.240 --> 0:21:02.359 sound can reson nate outward. If you don't have a 0:21:02.440 --> 0:21:06.359 resonance chamber, then the vibrating strings would be pretty quiet 0:21:06.880 --> 0:21:09.560 and it would be difficult to hear it over other instruments. 0:21:10.200 --> 0:21:13.720 The way you produce vibrations with a stringed instrument, whether 0:21:13.840 --> 0:21:17.280 it's by strumming or plucking or boeing or striking the strings, 0:21:17.680 --> 0:21:21.000 will help shape the sound as well the strings themselves 0:21:21.080 --> 0:21:22.879 and the design of the instrument as a whole. So 0:21:23.000 --> 0:21:26.720 all of these things contribute to the specific overtones that 0:21:26.840 --> 0:21:29.800 are created when you play that instrument. And that's why 0:21:30.480 --> 0:21:33.960 each of those instruments sounds different from the other instruments. 0:21:34.359 --> 0:21:39.199 Whether it's a banjo, guitar, lute, mandolin, harp, piano, violin, 0:21:39.320 --> 0:21:42.879 or whatever. It's the specific qualities of those types of 0:21:43.000 --> 0:21:46.760 instruments that gives each one its own sound. Another thing 0:21:47.119 --> 0:21:50.200 that shapes the quality of the sound is whether the 0:21:50.280 --> 0:21:54.520 strings are doubled. Some instruments double up on strings for 0:21:54.600 --> 0:21:58.359 specific notes, like the mandolin tends to do this. I 0:21:58.440 --> 0:22:00.720 think it was done that way in order to make 0:22:00.800 --> 0:22:05.399 my fingertips cry, but really the more likely original reason 0:22:05.560 --> 0:22:08.600 was it was done to amplify the volume of sound, 0:22:09.160 --> 0:22:12.520 because as instruments got louder, people had to figure out 0:22:12.600 --> 0:22:16.399 ways of making older instruments be able to play along 0:22:16.520 --> 0:22:20.200 with newer, louder instruments. And some of you may be 0:22:20.280 --> 0:22:23.000 wondering why I'm bothering going through all this stuff, and 0:22:23.080 --> 0:22:26.080 it's really just to illustrate that over time, we've really 0:22:26.160 --> 0:22:28.800 learned how to shape instruments so that they can harness 0:22:28.920 --> 0:22:31.359 the power of physics, even before we had a full 0:22:31.480 --> 0:22:35.840 understanding of those physics. And this required an enormous amount 0:22:35.880 --> 0:22:39.760 of trial and error as people learned what did and 0:22:39.960 --> 0:22:44.360 didn't work, and then taught this to younger generations who 0:22:44.720 --> 0:22:49.280 improved upon previous methods while learning more about the actual 0:22:49.359 --> 0:22:52.639 science behind the practice. The reason I went with stringed 0:22:52.640 --> 0:22:55.560 instruments after percussion is that it's pretty easy to get 0:22:55.600 --> 0:22:58.800 your mind wrapped around what is creating the sound, because 0:22:58.840 --> 0:23:03.040 ultimately it's the vibration of those strings. Although those strings 0:23:03.160 --> 0:23:05.600 could be feeding vibrations into some other part of the 0:23:05.680 --> 0:23:09.200 musical instrument, but we can see the strings vibrate, So 0:23:09.320 --> 0:23:11.440 this one's pretty easy to grasp. You know, you see 0:23:11.480 --> 0:23:13.480 it and you're like Oh, that's what's making the noise. 0:23:13.600 --> 0:23:17.639 But what about instruments that you blow into. Well, it 0:23:17.800 --> 0:23:20.960 helps if we continue our division of the instruments into 0:23:20.960 --> 0:23:24.560