Hey Eddie,

I appreciate you taking  the time to share your vast knowledge of
systhsis it has been a great blessing for me.

Next time I'm in the UK I will look you up.

Peace

Michael Norman

Introduction

Almost every day I receive emails or questions posed in forums about programming and usually they are questions specifically to do with programming synthesizers and samplers and always about emulating a sound that has been heard on a popular record or 'trying to sound like' someone or a band. Whereas these form the bulk of the queries posed to me there are also the few that are far more technical and specific to a stream of data that is required to create whatever the enquirer is hoping to achieve.

For these reasons I have decided to create a detailed tutorial in synthesis that will be ongoing, from month to month from absolute beginner to godlike superhero advanced programmer whiz kid.

The method I am going to use to help you in understanding the terminology and definitions and what each part is and does is a system that has existed for centuries and works extremely well in every aspect of your life. It is a system that speed reading specialists, memory recall centres and even high powered executive training programs use. It is called 'Tagging' or 'Linking'. It is the simplest and most effective 'remembering' tool. You have used it since you were a child.

Every time you were asked to draw a house in a field, you would draw a strong big house on green grass with a huge sun that was always yellow, red or orange with a tree and a cow. Of course some people drew the same topic in the Picasso mould or surreal a la Dali, but on the whole, the picture is almost always the same. Why? Because we remember things that have an effect on our senses, be it touch, smell, taste, hearing or visual. The strong colour of the sun and the size of it are a great way of remembering what a sun looks like. The big house in the centre of the drawing will always stay in your mind. The cow is always alone and strongly accentuated and is always totally out of size in comparison to the house. The ground is always green grass and the sky always blue and if there is a cloud then it is always one big round cloud. These images are strong and always stay in memory. The same technique is used in tagging. We create an image rich in as many of the senses as possible and that will always stay in our minds, far stronger than having to learn things in parrot fashion.

I have used this technique all my life and now do it unconsciously. Not only does it work but it is also fun as the tool for tagging is your imagination and nothing is stronger or stays longer in your memory than an image created out of your imagination.

Probably by now you feel that I require a great deal of help and that there are certain places for people like me, comfortable places that offer 24 hour security and in depth treatment. You are probably right but not for the reasons for this tutorial.

So, let us begin this journey.

Understanding Sound

To understand any part of synthesis you need to understand sound, what it is, how it moves, how we perceive it and why we perceive it the way we do. Once you understand this then shaping it or manipulating it becomes so much easier.

Sound is the displacement of air around the source and how we perceive that displacement. Right, what does that mean? Think of the best and most commonly used analogy: that of dropping a stone in a pond and watching the ripples form. The ripples always move away from where the stone meets the water (source). The air displacement is the ripples created by the dropping stone. In this case we see the ripples. In the case of sound we hear the ripples (the displaced air). How do we hear the displaced air? Our eardrums pick up the displaced air and our brains then process the data as sound.

I could go into the details about the ear muscle vibrating and the eardrum being a chamber and on and on and on.but that is not what you want to know. The tagging image here is the ripple and has it ever occurred to you that when a picture is drawn of a guitar amplifier, with a guitarist playing loudly, you always see a few arced lines drawn coming out of the amplifier? Exactly like the ripples in the pond. In fact this image is always the same for speakers that are playing music. The picture or tag here is , again, always the same with arced lines starting as small arcs growing to large arcs and away from the speaker. Keep that image in your head and that constitutes sound, or more precisely, sound waves, like the ripples. Figure 1 illustrates this. I have deliberately used freehand so it will make you laugh and stay in your memory.

Fig1 SOUND WAVES

Now lets us look at the components that make up sound. There are three and really quite simple to understand if you apply the ripple analogy. The displacement of air or air pressure as is more commonly known creates the waves in fig 1 and is know as Sound Waves. The rate at which these waves occur is called Frequency.

So our first component of sound is Frequency.

1. FREQUENCY

This is simply calculated at how many cycles (waves) occur every second. These cycles are repeated so really we only need to look at how many cycles (waves) occur in one second. The result is measured as cycles/second and this unit of frequency is called a Hertz and the abbreviation is Hz. You cannot get simpler than that...how many cycles hit you in one second. Heinrich Hertz was a dude who worked with wavelengths and frequency, so we have to thank the man and it seemed only right to name this little calculation after him. I always remember the rent-a-car agency when I think of frequencies and Hertz and it makes me smile every time so remembering that name is easy.

To give you an example of how easy this is check out the following:

If you had 50 cycles hit you in one sec then that would be a 50Hz wave. There, simple and makes you look cool in the bar when you want to impress someone.or maybe not.

So it also follows and makes complete sense that if you had 10,000 cycles per second then that would be 10,000 Hz, but, because we don't want to have to write so many numbers every time a thousand appears we use the k letter to mean a thousand. So, 10,000 Hz is now written as 10 kHz. Now you look even cooler. There is a reason we do this and it's not because we want to look deep and complicated individuals but simply because of all the work that has been carried out on our hearing range in the past. And a range was formed, sure it varies but generally speaking, our hearing range is anywhere from 20 Hz, deep, to 20 kHz, high.

Now, let us think of that range and make life a lot easier by giving names you recognise to the frequency range. So: bass, midrange and treble are easy to remember and if you are old enough then that's about all that used to exist on hi-fi systems back in the days of armour and jousting. Now let us give those tags a frequency range and then all becomes so much easier to understand.

Bass: 10 Hz to 200 Hz

Midrange or mid , a term you hear a lot of engineers use: 200 Hz to about 3 kHz

Treble: 3 kHz to whatever the highest value you can hear.

It is important to mention, at this stage, what frequencies most natural instruments lie in. Not only will this help you later when it comes to equalisation and filtering but it also gives you a nice tagging point for the instruments.

Kick drum....20-150Hz

Bass......20-250Hz

Piano.......80-4500Hz

Snare......100-200Hz

Cymbal... 300-600Hz

Bear in mind that these are only guides and nothing more as there are so many different instruments with different characters and even the same instrument played differently will generate a different frequency range.

So we now know that higher frequency sounds are higher in pitch as there are more cycles per second and lower frequency sounds have fewer cycles per second. Easy.

Right now I think it is important to show you a frequency chart for all the notes on a keyboard or scale and the midi note numbers as well as this will come into play at a later date when we deal with synthesis and programming with the use of midi.

You do not need to learn this chart in parrot fashion but it is important to understand some of the frequencies that are used as, later, you will need to know these frequencies so that if you need to use equalisation or filters to shape a sound or remove or add certain frequencies, then the chart can prove to be invaluable.

In most cases, you only need to recognise the main frequencies for certain notes. For example: C4 at 261.63 Hz is a great reference point, because then you can find, easily, C5 or C3 etc..

I cannot stress how important frequencies are for the understanding of sound and synthesis. Engineers live by them as do producers and Sound Font developers.

If there is one piece of information that overrides any other in terms of importance it is the understanding of frequencies. How often have you tried to mix your track only to be mystified by the result? Terms like 'muddy' or 'thin' spring to mind and these are all because the mixer or producer does not have an understanding of frequencies and their effect on other frequencies in a mix.

Understand this basic concept and you will be armed with the most potent weapon. The rest of synthesis is the understanding of how to shape these frequencies to create new ones or to bring out the best in a spectrum of sound.

Waveforms and frequencies go hand in hand. Understand these two and the rest is all about using the tools.

So, let's get on with the CHART.

The Chart

 Midi No  Note  Keyboard  Freq  

As you can see from the funky chart that for every octave you go up you double the frequency and it is the same in reverse for every octave that you go down, in that case you halve the frequency. The other cool part of this chart, are the midi numbers that go along with every note. These will become very useful later. For now, you don't need to worry about them too much.

Example: C4 is 261.63 Hz. To get to C5 we double the frequency so it is now 523.25 Hz. And if we wanted to go from C4 to C3, it would be 130.81 Hz. There, a few secrets to throw about.

Now let us create the tag for this whole sound thing. I always imagine a wave as a 3 dimensional entity and with that I attach colours and size. So, for a low frequency wave I will think of it as a large and flowing wave with nice warm colours like orange or deep red and the whole image is nice and slow. For higher frequencies I use smaller and faster waves and in harder colours like bright yellow or striking blue. This image is then enhanced further by having a person standing in front of the waves, usually me, but my name is Hertz and I am listening to these waves in a rent a car. Although this may now confirm the urgency for me to seek therapeutic help, it is the best way for me to remember things. You can create whatever images or story lines to the definitions in this tutorial. They are your images and must work for you.

2. AMPLITUDE

Generally speaking this means the loudness or level of a sound or waveform . I prefer the word waveform for sound as it is the form or shape that the waves take and the further we go into this tutorial the more that term will make sense as waveforms vary in shape and character so, from now on, I want you to use the word waveform for sound. It is better defined with a simple graph. In fact, now is as good a time as any to introduce you to graphs. Enter fig2.

Fig2

As you can see, the waveform, it's actually a sine wave but don't worry about that for now as that is the next subject we will cover, is 2 cycles and I have arrowed in the second cycle, no difference which cycle I arrow as they are both repeats, anyway I had to arrow the second cycle so as not to intrude on the amplitude line in the first cycle. The height or peak of the waveform is the amplitude and the length is measured as 2 cycles and this is done very simply. Imagine a sound and how it starts. It starts from 0 then goes up, hangs about and then drops off. In the diagram you can see the waveform starts at zero, goes up, drops to zero then goes to the negative area and then climbs to zero again. This is using the wave theory we defined earlier and all waveforms are represented like this, as a graph, and how each cycle behaves or how a number of cycles behave in relation to each other. For now you do not need to worry about complex waveforms and any other factors regarding waveforms as we will deal with them as we go along, at your pace, that way you do not feel as if there is too much information to learn. This is meant to be fun so let's keep it that way. Later we will look at wavelengths, decibels, phase etc.. so for now we need to look at the most basic waveforms that are found on synthesizers , what they are, how to draw them graphically and what type of sound each waveform produces. This leads onto the next subject: WAVEFORMS

WAVEFORMS

The final most important component of sound is TIMBRE. This is what defines the tonal quality of a sound. A C4 note played on a piano and at the same level as a C4 note played on a saxophone does not produce the same sound or timbre. They are both the same level and both played at C4 but both have distinctly different sounds or timbres. Timbres are made up of waveforms and it is these waveforms that go to make up the tonal quality of a sound. This is called timbre.

Although there are countless waveforms and some are very complicated in nature, there are certain standard waveforms that are always seen on analogue synthesizers or any modern day synthesizers, be it hardware or software, that have synthesis capabilities.

They are as follows and are shown graphically and you can even listen (audition) to them so you can familiarize yourself to the way they sound.

Saw at C4 (Right Click 'Save Target')

Sine at C4 (Right Click 'Save Target')

Square at C4 (Right Click 'Save Target')

Triangle at C4 (Right Click 'Save Target')

Noise (Right Click 'Save Target')

These waveforms have their own sonic (sound) qualities and if you have a basic understanding of what they sound like and what they are usually used for then you are half way there to understanding how to manipulate them.

Sine waveforms are great for creating deep warm basses or smooth lead lines. They can be used to create whistles, layered with kick drums to give that deep subby effect. In fact the sine wave is a pure waveform and the harmonic content is fundamental. That means that almost all other waveforms are created from sine waves. But don't worry about this for now as the theory will come later. All I want from you is to understand and tag the above waveforms. I use the actual waveform shapes as an indication to the type of sounds they can create.

The sine is a nice smooth flowing waveform.

Saw waveform, or sawtooths as they are more commonly known, have a rich and bright, edgy sonic quality about them and are great for creating strings, brass, huge Trance pads, searing leads and electro basses. Of course there is, as with all the other waveforms, far more to it than that, but, as I said, I just want you to get a general idea of what these waveforms are used for and how they sound. The real fun starts when we start to layer them or trigger one with the other, but that will come later when we get into synthesis.

For tagging, these waveforms have that jagged like shape so they are easy to remember.

Triangle waveforms are great for bell type sounds or wind type sounds like flutes etc.and I regularly use them for the FM type of sounds that you hear on Yamaha DX7s or FM7s, great and very useful.

These waveforms look like triangles so that makes life easier.

Square waveforms are great for brass and deeper wind type of instruments and are usually used along with other waveforms as they are quite strong and hard on their own. But they are invaluable as are the rest listed above.

As you can see the square waveforms look like a bunch of squares with their tops and bottoms missing and alternatively.

Noise waveforms are used more for effect than anything else but I find that they are fantastic for creating pads along with other waveforms like saws and triangles. You can also create great sea shore wave type of sounds or huge thunder or even some great Hoover type sounds when used with saws. Endless what you can do with these waveforms and for that reason alone you see that most synthesizers, software or hardware, have these waveforms as the main sound source. The rest is all about the actual synthesis or programming of these waveforms.

These are the easiest ones to remember, a mesh of what seems like radio static or just rubbish.

SO, there you have it, your first week's tutorial. A simple and basic explanation of sound and waveforms, what their characteristics are, how we perceive them, what they are used for and best of all ' the tagging method '.

Next week we will look at the different types of synthesis, a slightly more in depth look at waveforms, what is ADSR and how we use it to shape a sound, what are the components of synthesis and definitions for all the terminology and components in synthesis along with a bunch of some very cool looking graphs. Remember that the most important aspect of these tutorials is to tag every morsel of information so that you will have an easy way of remembering and understanding all the data. Enjoy these tutorials and have some fun whilst you learn. Oh, and don't forget the German rent a car dude, he comes up all the time in these tutorials.

Personal 1-2-1 Tuition Courses

Eddie Bazil (Zukan)
www.samplecraze.com