Name: 自分でコード化!サウンドシンセサイザー #1 - 基本的なノイズ (Code-It-Yourself! Sound Synthesizer #1 - Basic Noises)
Uploaded: 2021-01-14T10:14:12.000Z
Duration: 28 min 50 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

Hello Today we're going to look how to build a synthesizer from first principles.

I play the guitar, but I'm not a trained musician.

It's no word near an expert, but being a programmer and being interested in music, I thought, It's about time we have a go at trying to build a synthesizer.

This will be a software synthesizer, and I know you can get them, but I think it will be an interesting learning exercise.

I believe this will be a multi part video today.

We're only really going to look at the basics of what is a sound wave on How do we represent that on the computer system?

Going to share with you some code that I've written, which will allow you to play with these sound waves very easily.

Single single file of code you can pull into any project you like.

Those intro themes that you heard me play there were back to the future on dhe Godfather on they were replicated using my PC keyboard is it is an input on a square wave for an output.

No, that might not mean anything to you right now, but By the end of this video, you'll have a good understanding.

I should say now that this video is is really aimed at the beginner, perhaps both in sound synthesis and for programming, although I will throw in some programming tricks to make sure we got the more advanced programmers to keep them on their toes.

You can think of a sine wave as being air moving backwards and forwards to generate sound.

In fact, if you look at your loudspeaker, you know the code, you see it bouncing backwards and forwards imagine that here is when the sweet speakers switched off, the cone pushing out, going backwards, going forwards going backwards, going forwards going backwards.

The more it goes in and out, the louder the sound will be.

And that's called amplitude, so amplitude you can also think of in terms of volume.

Loudness professionals will measure amplitude in decibels.

Now, the basic formula for a sine wave is amplitude time.

Sign off the frequency Times time, the same way I got on the screen here is not centered around zero.

It's actually offset 0.5 because I'm going to use This is a visualization tool and it will make things a little bit clearer.

Result to understand on frequency is how many times we see a peak within a given time interval.

So if I increase the we could see here we could see we get more peaks.

As I increase the frequency we Seymour peaks and as I decrease it, we see fewer and I can change the amplitude.

I would just like to take this moment to point out how excellent this Tulis this is Desmond, stop calm, which is a free graphing and mathematical tool for educational purposes.

Now we'll understand frequency as being pitch, so high frequencies are high notes and lower frequencies are low notes.

And that's why I really Basie sounds, you hear throaty.

You see the speaker moving very slowly, but sometimes you can see it, but in high frequencies, he can't see it moving it all.

So we know these low frequencies are based on high frequencies are trouble.

All sound is made up of sine waves of different frequencies and amplitude.

And if we take sine waves of different frequencies and amplitude and abdomen together, we can create interesting textures on different sounding instruments.

So here's a little example of adding sine waves together.

Now the formula looks horrible And I'm afraid if you don't like maths, then probably synthesis isn't for you.

Uh, here we've got three sine wave equations with a fixed amplitude.

But we get to vary the frequency of each one of them.

Now, by adjusting the sliders we can take a frequency on, we'll add another one to it.

So if we had a very low frequency here, there we go to a high frequency and sea mounts a little bit.

That will have an interesting sound, and we can add a lower fundamental frequency to it, which is more dominant.

And just by manipulating sine waves in this way, we can create all sounds.

This project is really about coding a synthesizer.

I will be sticking to the Microsoft Windows platform.

That's because I've already written some code, which interfaces with the sound hard work and that's available to download below or fromthe one loan coded dot com website to keep it simple.

I'm going to create a Win 30 to console application, and we'll call it sounds synthesizer.

I wanted to be an empty project that generates lots of stuff I'm not going to use, and we'll keep it as a consul project.

So we're not going to bother with Windows.

Gu Ys o r controls Everything will be handled just a the command prompt, and this is a nice way and to make it easy for people to learn, I like consul programs because they're limited in their access and their abilities to display information.

This focuses you to think really about what you're doing, creating an empty project that will create a source file c++, and I'm going to call that one made all of the code I'm going to include for download and in this video is written to be accessible.

It's not written to be the most optimal or intelligent way to solve the problem.

I'm learning about how to do synthesis is and producing this video, and I'm hoping that through learning myself, all the people might try and avoid some problems.

I will be using Standard Library quite a bit, so I'm going to throw that in there just to keep my coat simple.

We wanted an in Maine program starts on return to Syria.

Now I mentioned before, we're going to be cheating a little bit.

I've already written a file which will access the sound hard work for us, and you just have to take my word for it.

That this file There's nothing off the present data to the sound card.

This is a starting point, I think, in a future video.

But right now I think let's get stuck into actually generating some noise.

I've already created a file which will talk to the hard work for us.

But at the existing, I said it's called one lone code a noisemaker don't age.

But really, all it is doing is accessing the sound hard work, creating a threat in the background on presenting those with a hook to apply data to the sound card.

I will explain all of that in detail in a future video, right?

I've created a short program here, which lists all of the sound hard work available on the computer on DDE Crazy instance.

Off a class called I will See Noisemaker Cold Sound.

It's using the first device that it finds, which is usually assistance default sound device.

I'm also going to now include some additional numbers and we'll have a look at what these mean.

I want the number of channels to be one on.

I'm going to put into magic mystery numbers for now into the end.

You see that actually, our default numbers provided by this class so feel free to use it without making these modifications.

So why is noisemaker using a short here in angle brackets?

Well, let's have a look back at does Most powered Graf, take the original way.

Bring back our existing way, for we need to represent this way form a smoothly as possible on a computer.

A computer will only be able to store numbers digitally to a fixed amount of precision.

We can emulate this by applying, uh, the second function here.

Now I will go into what this function is doing just yet, but it's a nice way of visualizing what happens as we as we apply more bits to represent the numbers that represent the sine wave.

So a CZ we increase the number of bits we can see that the approximation to the sine wave becomes more and more accurate.