The word techniques encompasses a large variety of meanings, not only is it the way or means to do something but also the skill, operation and approach to get that something done. All techniques are of a very personal nature, and can be adapted to one's own style of playing, once you have achieved a certain basic level, these techniques will grow with you in terms of operation and creativeness.

The most fundamental technique is to understand the instrument you will be using, not only in its capabilities but in the way it is eventually heard by the listener. We will be examining the synthesiser and its associated equipment, not only in their workings but the basic techniques involved in using electronic instruments especially in various forms of music.

Understanding your synthesiser

When you sit down with your synthesiser, whether it be keyboard operated or modular based the understanding of what actually happens when you rotate a knob or depress a switch is of the utmost importance.

A synthesiser completely and simply reverses the processes by which our brain discerns sound. Sound is broken down by the human ear into three basic elements and their possible changes. These elements are: Pitch, Timbre and Volume. Let us take a closer look at how these can be thought of in synthesiser terms.

Pitch

The frequency of 'cycles' per second determines the pitch of a soundwave. Frequency is measured in Hertz (Hz) units, one Hz equals one cycle per second. In musical references we use common relationships, i.e. A = 440Hz or the tonic solfa, do-re-mi scale.

Changes in pitch

When referring to changes in pitch we are relating to vibrato, tremolo and pitch bending. When you come to make use of a change in pitch there are certain questions to ask yourself:

(a) How many times do I want the pitch to go up and down each time I play a note?

(b) How many times per second do I want the pitch to rise and fall (fluctuation speed)?

Figure 1 shows that in vibrato the pitch fluctuates regularly above and below the basic frequency of a note, but in pitch bend the pitch rises or falls just once.

You must be clear about this difference because on the synthesiser you will be using two completely different modules to synthesise these effects.

Timbre

Timbre or tone colour depends on the shape of the sound wave in operation. Any regular waveform can be broken down into its fundamental frequency and a finite number of harmonic components which are odd and even multiples of the fundamental, these are otherwise known as overtones.

It is the ratio of each of these harmonics in relation to others which determines the waveform, therefore any increase or decrease in the amount of harmonics will change the timbre. When we talk of a sound being bright, clear, heavy or dull we are responding to its timbre.

Taking a sawtooth wave as an example, Figure 2 offers visual confirmation that any complex periodic wave consists of a number of sine waves (the fundamental, which is of greatest intensity and lowest pitch, and harmonics or overtones which are simple multiples of the fundamental and of lesser intensity).

The waveforms and their uses

Waveforms can be broken down into two basic groups, periodic and aperiodic. Periodic waveforms are those that have pitch and are of a repeating nature, i.e. in a chain of complete cycles the cycle being produced looks like the preceding cycle. Aperiodic waveforms do not have any repeating patterns, sounds with aperiodic waveforms have no pitch, e.g. those made by wind, surf, snare drum, etc.

The most common waveforms found on a synthesiser are as follows:

The sine wave has no harmonics, it is a very pure tone, it is a very rounded sound akin to that of a tuning fork.

A very basic waveform having very few harmonics, a triangular wave may be changed into a sine wave by the use of the Low Pass Filter. The timbre is soft and rounded, excellent for flute and vibe type effects.

The sawtooth wave, sometimes known as a 'ramp' waveshape is rich in all harmonics, and one of the most useful to the synthesist. Used for string, brass, voice and other harmonically rich sounds. Due to the plentiful supply of overtones the VCF is highly effective.

The rectangle or square wave is variable depending on the width at the top, called the pulse width, when the top and botton widths are of equal distances it is a square wave, and possesses the hollow qualities of the reed family. Like a clarinet there are no even harmonics.

As the pulse width proportionately decreases, a strong shift in tone colour occurs, the sound becomes 'nasal' in quality, i.e. oboe or harpsichord.

Noise signals are unique in that they are irregular, have no clear pitch and contain a mixture of all frequencies together. Noise can be used as a sound signal source for special effects, and as a control signal for irregular modulations. There are two common forms that noise usually takes, these are pink noise and white noise.

Pink noise has a greater proportion of low frequencies than high, being perfect for thunder, waves and deep percussive effects.

White noise is noise which is musically balanced; high and low frequencies sound equally loud, white noise is very useful to synthesise wind, surf, gun shots and rim-shot percussive type sounds, it is also very effective when used as a modulation signal to obtain the sound of the musicians breath when playing a wind instrument - again the VCF is well applied here.

Changes in Timbre

We do not pay much attention to changes in timbre in the everyday sounds we hear around us, eg. traffic, talking, telephone etc. Only when something dramatic happens, ie. car crash, shouting, increase in telephone volume does one pay any clear attention.

If you hear a trumpet being played softly, you hear a rounded and mellow tone, if played loudly the sound becomes bright and sharp, a clear indication of how timbre changes in proportion to volume. Applying vibrato to a brass instrument will also cause small variations in timbre which in this case, are proportional to the regular fluctuations in pitch. You will see the same type of cyclic pattern as in Figure 1.

Try to visualise changes and timbre in graph formation, this is an important skill in playing and understanding the synthesiser.

Volume

When we relate to a sound being too soft or loud, we in fact mean its average volume albeit that the amplitude is constantly changing. With a synthesiser it is much more important to think about how the volume changes over time. For example how do you really differentiate between a flute and piano if they played the same note? The most obvious difference is the way the volume rises and falls. In this way volume does not have 'static' characteristics like pitch and timbre, the other two elements that determine 'sound quality'.

Changes in Volume

In Figure 3 you can see from the graphs the characteristic patterns produced as volume rises and falls during one note. The changes in volume on a synthesiser are effected by the envelope. Again, develop an understanding of what happens when you hear a sound, how does the volume rise?

Does it remain constant? What is the decay of the sound? All these factors relate to every sound made.

Let us now relate this to the synthesiser, the pitch is effected from the Voltage Controlled Oscillator (VCO), the timbre is created from the waveshaping circuitry on the VCO and finally altered by the Voltage Controlled Filter (VCF) or resonance controls and the volume is processed through the Envelope Generator (EG) and Voltage Controlled Amp (VCA).

Whether you switch link, patch link or pin patch, to synthesise any sound you should use the technique of producing the sound in the following steps.

Analysis

Analyse the sound you have in mind, break it down into its three elements and look at them individually.

(a) What is its pitch?
(b) What kind of timbre does it have?
(c) How does its volume change over time?

Selection

Select the modules you will need accordingly to the results of your analysis. Decide which modules will be able to produce pitch, timbre, and volume and their respective changes. You must have a clear concept of exactly what each module is capable of.

Programming

Programme your selected modules by patching them together and adjusting their control voltages. Programming is the end result from selection and analysis, hooking up in the correct order to obtain the effect required.

If you look at the synthesiser in this way, a far more logical direction to sound and its characteristics is obtained and can be directed to any form of sound make up and synthesis.

In the next article we will be looking at the modules and following the sound to its end.