Synth 101: a Guide to Synthesizer Terminology

What Is a Synthesizer?

Before we jump into our list of essential synth terms, there’s one burning question we should first take a look at: What exactly is a synthesizer?

Essentially, a synthesizer is an electronic instrument that creates sound by generating and manipulating audio signals. Whereas electric guitars instruments make sounds with vibrating strings or air columns, synths use components like oscillators, filters, and amplifiers to sculpt sounds entirely from scratch – or even mimic other instruments.

Synths are closely associated with genres like dance, industrial, and electro, but they’re actually super versatile tools with plenty of uses – look hard enough, and you’ll find them in just about every genre. Lush pads in ambient music, quirky beeps in indie pop, soaring melodies in prog rock, right up to atmospheric textures in the harshest black metal or face-melting EDM basslines. Synths can do it all.

Famous Synthesizers

Since breaking out in the ‘60s, a handful of synth brands have achieved bona fide legendary status, thanks to their innovative designs, iconic sounds, and endless popularity. Names like Moog, Korg, Roland, Nord, Yamaha, Sequential, and Arturia have all shaped synth evolution, each offering their own take, their own leap forward.

Over the years, these powerhouse brands have done much more than drive synth development, though – with their powerful offerings, they’ve literally been the catalyst for whole new genres. How would Pink Floyd have sounded without their vintage analogue synths? Take away Roland’s legendary drum machines, and a whole generation of drum and bass would vanish with it!

Synth 101

In a little while, we’ll give you a complete rundown of all the essential terms you need to know if you’re going to break into the world of synths. But first, let’s put a few of these terms into context. Cutting through the jargon is one thing, but understanding how it all fits into synth design and usage, and how everything interacts with each other, is vital if you want to start making tunes as soon as possible.

The Building Blocks of a Synth

At the heart of every synthesizer is an oscillator. This component is responsible for creating the initial sound. Oscillators generate waveforms, which are basically different types of sound shapes, each offering its own character. There are four basic waveforms that you’re most likely to come across: sine, which has a smooth, almost pure tone; square, with a hollow, woody sound that introduces some odd but interesting harmonics; saw, which is a great choice for basslines and leads owing to its bright and buzzy edginess; and triangle, which sounds like a softer version of a sine wave, but with a bit more warmth. Many synths have multiple oscillators, so you can blend multiple waveforms together to create all manner of different sounds.

Once the raw waveform is generated, the voltage-controlled filter (VCF) and voltage-controlled amplifier (VCA) get to work. The filter acts like a sculptor, cutting or boosting frequencies to mix up the tone, such as by removing harsh high-end or adding resonance. Then there’s the amplifier, which controls the volume and dynamics of your sound to add expressiveness or punch. Together with the waveform, these features give you total control over the tone and intensity of your initial sound, ready for further refinement.

Shaping Your Synth Sound

Once you’ve got your basic tone up and running, it’s time to start tinkering! This is where sound-shaping modulation tools come into play, adding motion, character, and complexity to your tones. One of the most important is the envelope, often labelled ADSR – that stands for Attack, Decay, Sustain, and Release. These parameters change how a sound behaves over time, including how quickly it starts (attack), how soon it fades (decay), how long it holds (sustain), and when it trails off (release).

Next up is the LFO, or Low-Frequency Oscillator. The oscillator we talked about earlier creates the notes you hear, but an LFO moves too slowly to generate pitch. Instead, this one modulates other parameters. Want your pitch to wobble, or your filter to rhythmically pulse? That’s LFO territory.

Types of Synthesizers

Synths come in many flavours, so to find the right one for your needs, it’s important to know exactly how they differ. First, there’s monophonic vs polyphonic synthesizers. A monophonic synth can play only one note at a time, which works great for basses and leads, whereas polyphonic synths can play multiple notes simultaneously, making them a great tool for chords and rich pads.

Then there’s the little matter of how your sound is generated. Analog synths use electrical circuits to create warm, organic tones, while digital synths use computer algorithms to craft more precise, complex sounds. Hybrid synths sit somewhere in between, taking the flexibility of digital and combining it with some good old analogue warmth.

Finally, let’s talk synthesis methods. The most common is subtractive synthesis, where you start with a harmonically rich waveform and subtract frequencies to leave behind only your desired tone. Additive synthesis, as the name suggests, is the exact opposite of this, adding sounds by stacking multiple waveforms together to build a complex tone. Frequency Modulation (FM) synthesis is a method of modulating one oscillator with another for a more complex, metallic timbre. Then there’s wavetable synthesis, which is a little more complicated. This one involves sampling a stored waveform and repeatedly reproducing it at different rates, each time producing a different frequency or pitch. Each reproduction, called a wavetable, imparts different characteristics, and by modulating through different wavetables, you end up with a modern, harmonically rich digital sound.

Controls & Interfaces

Of course, getting the most out of a synth doesn’t just mean creating a wicked tone – you need to control it too. One of the most popular creative tools is the arpeggiator, which automatically plays the notes of a chord in a rhythmic pattern to add movement to your melodies. For more complex patterns, there’s also the sequencer. This lets you program a series of notes or rhythms to play back automatically, which is perfect for looping basslines, leads, or even full-blown compositions. Then there are features like glide (or portamento), which lets you smoothly slide the pitch between notes, rather than jumping directly from one to another, creating a more flowing, expressive sound. Finally, with the all-important sync, you can make sure your synth stays perfectly in time with the rest of your setup, be it another synth, a drum machine, or even your digital audio workstation (DAW).

Once you start getting into the swing of synth, you’re going to hear the word patch used – a lot! Just to confuse you a little more, this could actually mean two different things: it can refer to a preset sound, which is a pretty essential way of saving all those tasty chainsaw bass tones you create, or the process of patching – connecting modules together to create your own signal paths and modulations.

Synth Communication

Of course, when you’re using modular synths or creating a signal chain, you need everything to speak to each other, and that brings us nicely to arguably the most important part of synth control – communication. Most modern synths use MIDI (Musical Instrument Digital Interface) to send note and control data between devices. But in modular setups, you’ll also often encounter an analogue control method called CV/Gate. With CV, or Control Voltage, you can modulate almost all parameters like pitch, filter cutoff, or amplitude by sending varying voltages between modules, giving you hands-on, analogue-style control over your synth’s behaviour. Gate works alongside CV by controlling the timing, sending a signal that tells the synth when to start and stop a note – think of it like an on/off switch for each sound.

Synthesizer Effects

Once you’ve got your sound shaped and sequenced, it’s time to finish things off with a little sauce. Effects are an essential part of synth construction, taking raw ideas into a polished, finished product. Depending on how you use your effects, you can do everything from gently enhancing your sound to transforming it into something completely unrecognisable!

Reverb adds space and depth to create a feeling of stereo width, and it can make your synth tone play nicely with other instruments, too. Delay creates echoes, helping to fill empty space, add movement, and build suspense. If you want to thicken things up a little, chorus is a good option, adding depth and fullness to your sound with subtle detuning. And if you want to turn up the nasty, don’t sleep on distortion! We all know about guitar distortion pedals and how they can transform guitar tone into a raging beast, but the effect absolutely has a place in the synth world too. All that digital perfection sometimes leaves things sounding a little too clean and sterile – but a little grit and aggression can mess things up in the best possible way!

Essential Synth Terminology List

• Additive Synthesis: The opposite of subtractive synthesis, additive synths build sounds by layering multiple sine waves, each representing a harmonic of the desired tone.
• ADSR: Attack, Decay, Sustain, Release – the four stages of an envelope that shape how a sound evolves over time, from the moment a key is pressed to when it’s released.
• Amplifier/VCA (Voltage-Controlled Amplifier): Controls the final volume of a sound, typically in response to a control voltage or envelope.
• Amplitude: More typically referred to as volume, amplitude is the strength or height of a waveform, which directly affects how loud the sound is.
• Analog/Analogue: Analog hardware and signals use electrical circuits to generate and shape sound. When it comes to synths, this means analog waveforms are infinitely variable, as they aren’t bound by the limitations of digital’s binary signals. As a result, some say analog synths have a warmer and smoother character than digital alternatives. Analog vs analogue comes down to your location, with analogue being the preferred British spelling.
• Arpeggiator: An arpeggiator is a type of sequencer that plays the individual notes of a chord in a cascading pattern, be it ascending, descending, or something a little more random. This adds movement and variation to your melodies.
• Attenuator: A control that reduces the strength of a signal, often used to fine-tune modulation depth or output levels.
• Chorus: An effect that thickens a sound by duplicating it and slightly detuning or delaying the copies, simulating multiple instruments playing at once.
• Clock: A rhythmic pulse that acts as a timing reference, which you can use to synchronise sequencers, arpeggiators, and other time-based modules or gear.
• CV: Control Voltage is a control method you can use on almost any parameter, like pitch or filter cutoff. Synths typically use a rule of 1 volt per octave, with octaves increasing in voltage the higher they get.
• Cutoff: The frequency point at which a filter begins to reduce or eliminate certain frequencies. This is a common tool for controlling synth parameters, drastically affecting your sound when employed.
• Delay: An effect that plays a copy of a sound after a short, definable period, often with feedback, to create space-filling echoes or rhythmic repetitions.
• Digital: The opposite of analogue, digital synths use computer-based processing to generate and shape sound. They offer high precision, greater flexibility, and more complex features – but possibly at the cost of reduced warmth and smoothness (compared to an analogue synth).
• Distortion: Adds grit, warmth, or aggression by clipping the waveform and generating additional harmonics.
• Envelope: Shapes a sound’s dynamics over time using Attack, Decay, Sustain, and Release phases to control volume, filter, or pitch behaviour.
• Eurorack: Eurorack is a physical modular synth format with standardised dimensions and power. Developed in the ‘90s, it’s now the most popular form of modular synth equipment, allowing users to build flexible, custom synth systems from a wide range of modules.
• Filter/VCF (Voltage-Controlled Filter): A filter alters tone by reducing or boosting certain frequencies, using voltage inputs to control its behaviour. Filters tend to focus on certain frequency ranges, each imparting a different effect:
  • Low Pass: Only frequencies below a specified cutoff point can pass through the filter
  • High Pass: Only frequencies above a specified cutoff point pass through the filter
  • Band-Pass Filter: Allows only frequencies within a defined range to pass through
  • Notch Filter: Also called a band-stop filter, this filter does the opposite of a band-pass and blocks frequencies within a defined range, often used to scoop out certain undesirable frequencies.
• Frequency Modulation (FM): Frequency modulation uses a controlled voltage to affect an oscillator’s waveform, affecting parameters like pitch, and volume. FM synthesis, on the other hand, uses the frequency of one waveform to modulate another waveform, creating harmonically rich and complex tones in the process.
• Gate: A signal that tells the synth when to start and stop a note, essentially acting as an on/off switch for sound generation.
• Glide/Portamento: Smoothly slides the pitch between notes instead of jumping directly from one to another. This is often used for expressive leads and bass lines.
• Hybrid: Combines analogue warmth with the versatility of digital components into a single synthesizer to offer the best of both worlds.
• LFO (Low-Frequency Oscillator): A slow-moving oscillator that’s typically used to modulate parameters like pitch, filter, or volume over time.
• MIDI (Musical Instrument Digital Interface): A digital communication protocol that allows electronic instruments and software to send and receive performance data.
• Modulation: The act of altering a synth parameter over time to create changes in your signal. By using an LFO, envelope, or external source, you can modulate almost any parameter, changing settings like volume, pitch, and width, and adding movement and expression to your sound.
• Monophonic: Refers to a synth that can only play one note at a time, often used for basslines and leads.
• Noise: A non-pitched, static-like sound source, often used for percussive hits, effects, or to add texture.
• Oscillator (OSC): The sound source of a synth that generates a repeating waveform, forming the core of the instrument’s tone.
• Patch: A saved or manually created configuration of synth settings, routing, and modulation that defines a particular sound.
• Patching: Physically or digitally connecting different modules or components to create a custom signal or modulation path.
• Polyphony: How many notes, or voices, a synth can play at the same time. This can be further broken down into the following categories:
  —- Monophonic: One voice at a time
  —- Paraphonic: Two voices that share a filter, envelope, and amplifier
  —- Duophonic: Two voices that have their own filters, envelopes, and amplifiers
  —- Polyphonic: Capable of playing multiple voices simultaneously, allowing for more complex chords and harmonies. The number of possible voices ranges from 4, 8, or 16 for analogue synths up to 128 (or even higher) for digital synths.
• Pulse: A waveform characterised by a sharp, buzzy tone, often used for its rhythmic energy and adjustable pulse width.
• Pulse Width: How long it takes for a waveform to travel from its highest to lowest points, or peak and trough. This can be adjusted to create an interesting phaser effect.
• Resonance: Boosts the frequencies at the filter’s cutoff point, emphasising certain tones and adding squelch or sharpness.
• Reverb: An effect that simulates sound reflecting off surfaces in spaces of varying size, creating a sense of real depth and ambience.
• Sample: A pre-recorded audio clip or waveform that can be played back and manipulated within a synth or sampler.
• Saw: A waveform known for its bright, edgy character that’s rich in harmonics – great for cutting leads and thick basses.
• Self-Oscillation: The feedback that’s generated when a highly resonant filter begins producing its own tone, often used creatively in sound design.
• Sequencer: A tool that plays a programmed series of notes or patterns in a loop, controlling a synth automatically.
• Sine: A smooth, pure waveform with little to no harmonics, often used for sub-bass or mellow tones.
• Square: A hollow-sounding waveform with odd harmonics that’s often used in chiptune or retro synth sounds.
• Subtractive Synthesis: The process of shaping sound by filtering out the unwanted parts of a waveform to sculpt a desired tone.
• Sync: Keeps multiple synths, sequencers, or effects units running in time with each other, often using MIDI or clock signals.
• Triangle: A soft, rounded waveform that sounds like a mellow version of a sine wave. Useful for gentle leads and pads.
• Unison: When multiple voices play the same note slightly detuned from each other, creating a thick, lush sound.
• Waveform: The shape of a sound wave, which determines its starting tonal character; common types include sine, square, triangle, and sawtooth.
• Wavetable Synthesis: A synthesis method that uses a table of stored waveforms, allowing you to scan or morph through different timbres for dynamic sound shaping.

Summary

There’s no denying it; synths can feel a bit overwhelming when you’re just starting out. But with a little knowledge under your belt, that maze of sliders, knobs, and blinking LEDs will soon become your own playground of endless possibilities. And by understanding the key synthesizer terminology, you’re already well on your way to dialling in some killer tones.

It’s important to remember there’s no ‘right’ way to use a synth. Whether you’re crafting vintage pads, filthy basses, or mind-bendingly glitchy sequences, experimentation is the name of the game. The more you explore, the more you’ll realise just how powerful your synth can be.

So go forth and tweak, patch, modulate, and mangle! Your perfect sound is out there, waiting for you to make it. And if you’re looking for the perfect synthesiser to help get you there, don’t forget to check out our full selection of synths and workstations.