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Modular Synthesizers

1. Electronic machines and instruments that are used to shape frequencies and produce sound, were first invented in the third quarter of the 1800's. Monophonic and polyphonic synthesizers [1] were being experimented with, and began to shape the way the player was able to produce sound. The Modular Synthesizer, which was first invented by Robert Moog in the late 1960's, who was the pioneer of voltage control technique [2], and utilized this system as the fundamental basis for what became the modular synthesizer. In essence, the modular synthesizer is one in which can be both physical and virtual. What is meant by this, is that we conduct energy waves using the physical machine, that we often reference in theory. If you take a physics of music course, we often focus on the sound wave, while neglecting the way it is generated (the Modular Synthesizer is a generator). In our case, we will focus on the physical machine, or generator; the Modular Synthesizer. The Modular Synthesizer consists of separate, specialized modules that are connected with patches (not hardwired), in order to conduct, transfer, and shape the frequency of the voltage/wave, thus, ultimately producing specialized modules for each waveform. This type of voltage control system allows the player to not only have full control of the sound being produced, but also produces an infinite amount of possibilities in terms of waveform production.

2. Pieces and Their Function

The infinite qualities of a modular synthesizer are what make its composition so unique, dynamic, and a wide range of waveforms to create and experiment with, depending on the preference of the player. The most important thing to note about all types of modular synthesizers, is that they utilize three basic functions, in order to create transfer and output sound. It [The functions consist of the (audio)signal, the control, and the logic. Knowing this, we can go on to understand some of rudimentary parts that compose a modulator.

2a) VCO- Voltage Control Oscillator

The VCO is the physical component that creates a voltage/electrical charge, in turn creating a specific frequency and wavelength [3]. The VCO allows the player to generate a wave that is either a sine wave, a square and rectangle wave, a triangle and sawtooth wave, as well as step and pulse shapes. The initial beginnings of creating a sound using a modular synthesizer require generating a frequency, using the voltage control oscillator, which can then be used as input to other modules.

2b) Envelope Generator

An envelope generator is a fundamental part to all modular synthesizers. It is what gives volume to and shapes the voltage that is outputted by the VCO [4]. The envelope generator operates on the concept of ADSR; attack, delay, sustain, release. It controls the quickness or slowness of the rise and fall of the wave. The output of this generator usually goes on to feed into the Voltage Control Filter (VCF), which often produces a timbre or frequency contour, controlling the cutoff frequency of the signal.

2c) Voltage Control Filter (VCF)

The voltage control filter takes the wave signal that has now already passed through the envelope generator, and gives it resonance. The player is able to create a specific timbre to that frequency, particularizing its colours.

2d) Sequencer

A sequencer puts together and records a sound sequence from a series of events. Essentially, it remembers the modulation of the generator and VCF, and allows the player to program the sequence in such a way that the wave will always hit these points[5]. It is a pathway that has triggers that shape the wavelength as it passes through the operating system. In a sense, it allows the player to program the points of the path that it wants each frequency to hit, without constantly having to monitor and adjust its stride; it becomes an automated pathway for the generated wavelength to move through.

2e) Mixer

A mixer is an essential and necessary component for any and all electronic recording devices. It is essentially a traffic manager for all of the voltages and subsequent parts of the modulator. It conducts the overall sound that is generated from all of the parts. Simultaneously, it allows for other musical components to be added to and layered on top of the sounds that are being generated. One can create sound from a modular synthesizer, and additionally record sound from a guitar, let's say, and have the sound connected to the mixer, in order to synthesize the sounds generating from both the modular synthesizer and the guitar.

The aforementioned are just some of the basic compartments of a modular synthesizer. Their are other components that can be added to the soundboard that produce different effects and controlling options.

3. Relationship to Physics

It is easy to see the correlation between the physics of music, and a modular synthesizer. The former is a theory, while the latter is its subsequent practice. Understanding the underlying principles of the physics of music, provides the player with a cognitive manual of what each part of a modular synthesizer operates, and how it does so. The modular synthesizer is based on the fundamental notion of generating power, generating voltage, and essentially conducting sound. Understanding the physics behind sound, gives the player not only a visual image of how sound generation functions, but it also is an essential guide to understanding how to both generate a frequency and shape it. Modular synthesizers are, in essence, the physical counterpart of the physics of music. It brings the immaterial realm of wavelength and frequency into a material form, that is able to be created, controlled, and navigated, by the player.

In conclusion, the Modular Synthesizer is a wave generator, with assembled parts that allow the player to conduct, shape, form, and transfer the wave, in order to create different frequencies and sounds.


1. Wikipedia contributors. "Polyphony and monophony in instruments." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 1 Oct. 2016. Web. 9 Apr. 2017.

2. Wikipedia contributors. "Voltage controller." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 9 Oct. 2016. Web. 9 Apr. 2017.

3.Wikipedia contributors. "Voltage-controlled oscillator." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 16 Dec. 2016. Web. 9 Apr. 2017.

4. Wikipedia contributors. "Synthesizer." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 9 Apr. 2017. Web. 9 Apr. 2017.

5. Wikipedia contributors. "Music sequencer." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 10 Feb. 2017. Web. 9 Apr. 2017.