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Sound rarely is a smooth wave. It's more like watching an ocean wave as it crashes on the shore. Most sound waves have rough edges to them, multiple peaks and valleys. That's because sound waves usually are a mixture of frequencies. I want to show you a little bit about this because I think later it will help you as you build multiple tracks into a single stereo or monaural mix. So here we are back in Soundbooth and I have loaded up with bunch of different files. So, I am going to show you several different kinds of examples about how you can see sound.
I am going to start with the simple 440 tone again, but I am going to show you how you can build a chord and you a chord looks, because it's not just one line. It's a combination or collection of several tones combined together. So, here is the A440. (Tones playing.) And now I am going up, what's called the third in musical parlance. I am going up from A to C# and what's cool about this - you can hear that change. We are going to build a major chord and you can hear that major chord building. It's something comfortable for people who have been raised with western music and how that fits into pitches is kind of interesting, because going up a third, that comfortable leap - dom, dom - is actually going up 25% in terms of the frequency.
We are going from 440 to 550. We had 110, 1/4th, basically, of 440 and so going up the third goes up 25% above the original frequency. I will play that again. (Tones playing.) So, that's up 25% with the original note. So, we got a 440 and a 550. Now the next pitch in a major chord goes up a fifth, it's called, and the fifth is also very comfortable to our ears. And that one goes up 50% from the original pitch, which is also, I think, just really cool when you understand that the math of sound matches the way we hear things.
This one goes from 440 to 660. It goes up 220, in terms of the waves per seconds. You got a 440, 550, and 660 to build the 1-3-5 part of a chord and the last part is an octave. And the octave in the major chord is 100% above the original note. So, if it's 440 for the root, then the octave above that will be 880. So, that's the basic way that you build a chord, but we are using this tone, which is such a clean sound that it doesn't sound natural to us.
It doesn't really resonate in terms of how we would hear things in nature or hear an instrument being played. Let me show you why the sound here will look different than the sound being created, let's say, by a piano. So, I am going to change to a different file. Here is the view of a piano playing those same notes (Piano playing.) Now, notice all these extra little frequency lines here. That's because pianos, and every other thing that we hear in nature, has overtones. It's not just the original A440 right there. There are other little tones built into a piano because of the way piano strings vibrate.
They don't vibrate in a pure 440 cycles per second. There are little other vibrations built in. So, the whole piano sound of an A440 has a bunch of other frequencies added to it that give it this sort of richness that we hear when we hear a piano. It's not a pure electronic tone. Let me play some more for you as we go down at a deeper lever. We are going to start down here, an octave below. (Piano playing.) You can see that the bass notes have more overtones than the higher notes.
Now I want to just play up the scale to show you what that looks like. We are going just go right up the 12 tone scale. (Piano playing.) And you can see how those frequencies show up, but then all those overtones show up as well. Let me change to an organ, which is more complicated instrument. It has more overtones because of the pipes that are associated with an organ. It's the same a440 thing, we start with again. We will see how a440 is much more complex, move overtones than a piano. (Organ playing.) What I want you to notice also that as you add notes, you increase the decibel level, or the amplitude, and you can see that showing up here in the waveform is a higher amplitude to it, a greater distance from the peak to the valley of the waveform.
But it's not like an arithmetic function where you add one note, that doubles that decibel level. It always is unpredictable as to how adding one instrument or one note will adjust the decibel level, but just be aware that as you mix a number of tracks together later, that you will increase the decibel level every time you add an instrument. So, you need to watch that, that you don't go too loud, going beyond what's called full scale. I will show what the level of this one is here right now. (Organ playing.) If you watch up here, you see that's it getting to about 5 decibels below full scale, as it is called, dBFS.
You don't want to go above zero. So, I will just watch that as you build your pieces. Let's go to one more instrument. I want to show you how vibrato looks. This is a vibraphone. (Vibraphone playing.) You can hear the vibrato created by a spinning little tube inside of a vibraphone. Let me just zoom in on the frequency display to show you that.
Look how it vibrates here, up and down. That shows the vibrato as a frequency is actually changing a little bit. That's what creates vibrato. Let me show you the human voice because the human voice is pretty complicated, in terms of its waveform. I am going to zoom out on this one, so you can see the whole thing. Here is the waveform for this human voice, which happens to be my voice. (Male Speaker: We hold these truths to be self-evident.) Let's just take a look at the waveform. You can see that the waveform is not at all smooth. It's rough. It's like an ocean wave, as I mentioned earlier. It's crashing on the shore, all these little extra peaks and valleys, because it's a combination of lots of frequencies. If you look at all the frequencies here, you can see that my voice is just chock full of a variety of frequencies, with some dominant frequencies like a little bit, obviously, below A440, because I talk below middle C. And you can see how all these undertones and overtones combine together in just a voice.
(Male Speaker: We hold these truths to be self-evident.) If I look at a singing voice. (Woman singing: When the sun sets on the water's edge, a sky of yellow, blue and red.) She is changing her pitch a lot as she is singing various notes, rather than my sort of monotone. So, look at her pitch change over time. There you can see it, but her voice is also a combination of lots of overtones, and her pitch is obviously a little bit higher than mine, but again, not much higher, because she is an alto, I think. Soundwaves are not these various smooth sinusoidal sound waves, as we showed you with the a440 tone.
They are complicated, complex things, sort of like the waves crashing on the shore full of little frizzy edges to them and I think if you understand just how that works and how the frequencies work and how they all combine together, you will have a better idea of how to create a good audio down the road.
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