Exploring the Different Types of Synthesis: From Subtractive to FM


Producers use computer programs for sound synthesis. / Pexels


Have you ever wondered how digital software produces sound? There are many methods of sound synthesis, each of which has unique uses, applications, and results.

This article explores several types of synthesis, discussing the components, limitations, and evolutions of each.

Understanding the Basics of Sound Synthesis

Sound synthesis is defined as the electronic production of sound. The word “synthesis” comes from the idea of synthetic production, in contrast to using real instruments.

It works by generating sound waves through various methods. Common methods include:

  • Subtractive
  • Additive
  • FM
  • Wavetable

Sound waves, made by oscillators powered by a direct electric current, are the basis of synthesis. These waves come in different shapes, giving them unique properties.

Unveiling Subtractive Synthesis

Subtractive synthesis uses a simple oscillator to create waves, which are manipulated to change the sound’s pitch and intensity. It starts with a rich sound and takes out unnecessary components, hence “subtractive!”

Origins and Evolution of Subtractive Synthesis

Subtractive synthesis was the primary technique for digital sound production in the 1960s, 1970s, and 1980s. It’s still one of the most widely used methods due to how simple it is to understand and use.

Components of Subtractive Synthesis

First, waves are generated by an oscillator. Next, they travel through a filter section, which takes out unwanted or unnecessary parts. Lastly, the sound goes through an amplifier section, which refines it with various effects.

Popular Subtractive Synthesizers and Iconic Sounds

Everyone recognizes the iconic synth that begins Michael Jackson’s song “Billie Jean.” It was created with subtractive synthesis!

Diving into Additive Synthesis

In additive synthesis, waves are generated one at a time with specific properties and combined until the desired sound is reached.

Fundamentals of Additive Synthesis

The sounds we hear in our everyday lives are not made of a single frequency. Instead, they’re the sum of many frequencies. This is what additive synthesis is modeled on.

This technique allows musicians to build sound from the ground up. It is a precise method that is less common than other types of sound synthesis.

Applications and Limitations of Additive Synthesis

Additive synthesis provides limitless control over every part of the sound. It’s applicable in situations where producers want to make something sound precisely the way they envision.

However, additive synthesis is limited by the power of the producer’s computer. It uses massive amounts of data and can easily cause systems to crash under the load. The more complex control a producer wants, the better their machine will have to be.

Harnessing the Power of FM Synthesis

FM synthesis uses two types of oscillators: a modulator and a carrier. The carrier oscillator creates a sine wave, and the modulator changes its frequency.

Algorithmic Approach in FM Synthesis

FM synthesis is based on mathematics. A harmonic is created if the modulator is a whole number multiple of the carrier waveform. If it’s a non-whole number multiple, the sound is inharmonic.

This algorithmic approach allows producers to know what sound they’ll get quickly.

Exploring Complex Timbres with FM Synthesis

Harmonics have a whistle-like sound, which opens up a world of possibilities for unique noise in songs.

Due to the complex equations that go into FM synthesis, many producers choose to use VST synth programs that automate the process. This method allows them to enjoy the benefits of FM synthesis without using complicated mathematics.

Music studios also rely on professional tutorials, such as ones from Sonic Academy, to master this tricky synthesis method.


Sound synthesis recreates the sound of acoustic instruments like guitars. / Pexels


Understanding Wavetable Synthesis and its Evolution

Wavetable synthesis generates sound using single-cycle waveforms laid out in a wavetable, which is where the technique gets its name.

Wavetable Synthesis Techniques and Parameters

Wavetable synthesis is best for sounds that evolve, are metallic, or punchy. It’s not ideal for copying acoustic instruments. This makes it essential for producers who are looking for innovative audio to add to their projects.

Blending Traditional and Modern Sounds with Wavetable Synthesis

Since wavetable synthesis is well-suited for non-instrumental sounds, it’s great to use in combination with other synthesis techniques to complement acoustic instruments. It can add great effects to liven up otherwise typical projects.

In Conclusion

Generating digital sound is a complex process, one that sound engineers must master to craft unique, innovative music. With the choice of subtractive synthesis and other methods, producers can create any sound.

Whether you’re using wavetable, FM, additive, or subtractive synthesis, your creativity and dedication will help you create unforgettable projects.