Synth Lab: learn synthesis by playing

Six ways to make a sound

Subtractive synthesis

Start with a harmonically rich waveform, usually a saw or square, and carve it with a filter. Sweep the cutoff and you hear the harmonics disappear. Most classic analogue synths work this way.

Additive synthesis

Build a sound from sine waves, one partial at a time. Every tone is a mix of sine waves at different frequencies and levels, so additive synthesis lets you draw a timbre directly.

FM synthesis

Frequency modulation uses one oscillator to rapidly change the pitch of another. The ratio between them and the modulation index create bright, metallic and bell-like tones: the sound of the classic digital electric piano.

Wavetable synthesis

Morph smoothly through a table of single-cycle waveforms. Moving the position with an LFO or envelope makes the tone evolve while the note plays: the basis of many modern pads and leads.

Granular synthesis

Chop a recording into tiny grains, a few milliseconds long, and blend them into new sounds. In the Synth Lab you work with real recordings of voice, flute, saxophone and violin.

Physical modelling

Use mathematics to simulate how a real instrument vibrates. The Synth Lab models a plucked string (the Karplus-Strong algorithm) and a struck bell (modal synthesis).

The parts of a synthesizer

Learn this chain and you can find your way around almost any synthesizer: oscillator, mixer, filter, amplifier, output. Envelopes, LFOs and controllers feed in from underneath. They never make a sound of their own; they move the controls on the path.

1. Oscillator (VCO or DCO). The sound source. It generates the raw waveform and sets the pitch and the starting harmonic content.
2. Mixer. Balances the oscillators against each other and against the noise source before the filter. This is where the thickness of a patch is decided.
3. Filter (VCF). Removes harmonics. Cutoff sets where it starts cutting; resonance boosts the cutoff point. Most of a synth's character lives here.
4. Amplifier (VCA). Controls loudness over time, so a sound can fade, swell or snap.
5. Envelope generators (ADSR). Attack, decay, sustain and release. One always shapes the amplifier; a second on the filter makes a sound feel plucked, swelling or brassy.
6. LFO (low-frequency oscillator). A slow oscillator you do not hear. To pitch it gives vibrato, to amplitude tremolo, to the filter the wobble.
7. Modulation matrix. The routing grid: pick a source, pick a destination, set the depth. This is what separates tweaking a synth from designing sounds.
8. Keyboard and controller inputs. Velocity, mod wheel, pitch bend and aftertouch are modulation sources like any other. This is where a patch becomes playable.
9. Voice architecture. Mono or poly, voice count, unison, detune and glide: often the difference between a thin patch and a wide one.
10. Effects. Chorus, delay, reverb and drive. They sit after the synth but are saved with the patch, so they are part of the sound.

Frequently asked questions