Sound Design with synthesis (as opposed to field recording) is central to electronic music. Using either an additive bank of oscillators, samples and filters or FM gives an opportunity to make sounds that are real-time controllable and as a result are often better able to be integrated into compositions. Field recording offers a great opportunity for realism and identity, but sometimes post-recorded control of the sound is difficult - though digital audio tools are becoming more and more powerful.

Examples:

Oscillator banks allows control over individual harmonics/overtones with the possibility of controlling the development of a timbre over time in an interesting way.

   Take Off    Hermes    Ripple

Sampling and resampling allows layers to be piled up to give rich textural effects

  Chimoo    Aahticle    Oasis

FM is a pure parametric form of synthesis that allows instruments to be built with great detail and that are very responsive to dynamics and pitch behavior.

  Gongas    Epiano    Phlootle

Field Recording can be like a microscope on the audio landscape.

  RainStick

Simple FM Synthesis

Having written a book on FM Synthesis together with it's inventor, Dr John Chowning, I feel obliged to share... The basic building block of FM is the Operator – an element which typically generates a simple sine wave, which is a simple and mellow tone. When a second operator is allowed to “modulate” the first, harmonics are generated making the sound brighter. FM synths usually have a group of “operators” at their core, all connected together in some way, called an algorithm or matrix. Before you even begin to explore how FM really works, it is helpful to be able to “read” an algorithm or matrix. A good way to get a handle on this, is to break the model down into chunks that contribute elements of audio to a voice, and simply turn them up or down. To do this, you need to understand how the sound is built up in the algorithm, and how sound “flows” through it.

In the above representation, it is quite reasonable to think of sound flowing from left to right out of each operator, through the connecting pipes, then brightening the output of every operator that it flows through, until it arrives at the output on the far right. The only way for sound to come out of the system is “through” an operator. In the case of this configuration, or Algorithm, it can be described like this…

• Operator 4 outputs a sound - it is connected directly to the output. For the algorithm shown, all sound flows through this operator therefore its output level and envelope become “master” controls.
• Sound from operator 3 flows into 4, modifying its output and making it sound brighter. The output level and envelope of operator 3 define how much sound flows from it into operator 4.
• Likewise, the sound from operator 3 is already modified and brightened by the sound from operator 2 flowing into it.
• Along the top of the algorithm, sound from operator 1 is joined with the flow from operator 3 (modified by 2) into operator 4, adding its own effect to the overall result.
• And finally, the sound from operator 1 is being spun back into itself (just a if there were a clone of itself further upstream) before passing along the pipe into operator 4.
• When the output of any operator is OFF, no sound flows through it or from it.

Here are two other algorithms. Spend a moment to think about the sound flow in each one, ask yourself how each operator might        

affect the sound. For example, what happens in each case if Operator 3 is turned off? In the case of Algorithm 4 on the right, operator 4 would sound but without any modification at all; for Algorithm 5, operator pair 3 & 2 would become silent, but operator pair 4 & 1 would continue to sound, the sound of operator 4 still being modified by operator 1.