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Synthesisers Synthesisers have played a pivotal role in shaping music for well over over 50 years now. Conceived in the early 20th century, pioneered in the post war era and dominating the music industry in the 80’s, they’re now making a massive comeback. With the dawn of the transistor age / end of the dependence on the vacuum tube and alongside advances in the fields of computing, radio and broadcast to name but a few, the synthesiser has been evolving. It’s absolutely amazing to see that today these units are no longer the sole territory of the super rich or engineering geniuses. For as little as £30 you can access a whole new realm of music making and start to gain an understanding of how manipulating basic waveforms can open an infinite realm of sound.

What is a synthesiser?



In a nutshell a synthesiser is an instrument that generates electrical signal and manipulates waveforms in any one of many different ways (subtractive, additive, wavetable, FM or granular systhesis to name but a few) creating new timbres or even imitating other instruments. Often implementing a keyboard, they can also be controlled by a sequencer or other instrument controller, through the standard MIDI protocol. Here are a few common principles and components of the synthesiser - almost every commercially available synthesiser and music synthesis software package operates using these basic principles.

The piece of electronic circuit that produces a periodic oscillating electronic signal, often either a sine or square wave. An LFO (low frequency oscillator) is an oscillator that generates a signal beneath 20Hz (the lowest sound we can hear) and is generally used to control other modules within a synthesizer. LFOs are like little robots that turn knobs back and forth for you.

Filters are, generally speaking, tools for manipulating signals. A filter allows some frequencies to pass through unattenuated while significantly attenuating others. Low pass, band pass, band reject and high pass filters are common examples.

Synthesisers have played a pivotal role in shaping music



Envelopes The sound envelope (comprising of Attack, Sustain, Decay and Release, or ADSR) are defining characteristics of any sound - the initial transients, length and tail of a waveform which (together with actual frequency content) make that sound unique. In sound synthesis an envelope generator is employed that allows us to manipulate these parameters within a signal path to vary the resulting timbre and create new sonic landscapes.

Transistors Transistors are the building blocks of electronic circuitry, In synthesis a transistor is essentially used to amplify signals and and switch control signals. Transistors are much lighter, stronger than vaccum tubes and do not require time to warm up, and as such are used extensively in commercial audio products and recording equipment.

Capacitors A capacitor is a storage centre, that stores electrical charge, consisting of one or more pairs of conductors separated by an insulator. It fills up, empties and refills thousands of times a second to produce what we would call the output signal. Working together with resistors - the frequency of this output can be controlled.

Red Dog Music Education Catalogue 2016  
Red Dog Music Education Catalogue 2016