Field guide 04 · synthesis · ten patches from scratch

Every sound
is five
decisions

A waveform, a filter, an envelope on that filter, an envelope on the volume, and one thing moving. That is the whole of subtractive synthesis, and it is enough to build almost every sound in house and techno. Press Build on any patch below and it assembles itself one stage at a time while the controls move — so you hear what each decision contributes instead of arriving at a finished preset and guessing.

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Section 01 · interactive

The synth

Two oscillators, a sub, noise, unison, one filter with its own envelope, an amp envelope, a pitch envelope and an LFO. Every patch on this page is made from those, and nothing else. Play it with the on-screen keyboard or your computer keys — A W S E D F T G Y H U J K.

Rolling techno bass

Bass
1

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Waveform
Spectrum · 20 Hz – 18 kHz
Envelopes · amp & filter

Two honest simplifications. The FM modulator's depth follows the filter envelope rather than having its own — in Operator each operator gets a separate envelope, and that extra control is most of why real FM sounds better than this. And there is one filter, not two; a real patch often high-passes as well as low-passes. Everything else here behaves the way the equivalent controls in Wavetable, Operator or Analog behave.

Section 02

What the controls do

Not definitions — what each one is for, and the mistake people make with it.

Oscillators: pick your raw material

  • Saw has every harmonic. It is the default for anything you intend to filter, because there is something there to remove. Bass, leads, stabs, pads.
  • Square has only odd harmonics — hollow and woody. Organs, garage stabs, chiptune-adjacent leads. Pulse-width modulation lives here.
  • Triangle is a sine with a little grit. Soft sub-adjacent bass, mellow plucks.
  • Sine has one harmonic — the fundamental. Nothing to filter, so a sine's character comes entirely from pitch, envelope and distortion. Subs and FM carriers.
  • Noise has all frequencies at once. Not a note, a texture: hats, risers, breath, the click on a kick.
  • The mistake: reaching for a complex wavetable when a saw plus a filter would have done it, and then having nothing left to shape.

The filter: remove, don't add

  • Cutoff is the single most expressive control on any synth. Most of what people automate in dance music is one cutoff.
  • Resonance boosts a narrow band right at the cutoff. Below about 4 it adds character; above 10 the filter starts to ring as a tone of its own, which is the entire acid sound.
  • High resonance plus a low cutoff can produce enormous energy at one frequency. Watch your levels — this is the most common way to blow a mix up.
  • Keytracking makes the cutoff follow the note. Without it, high notes sound duller than low ones, which is usually wrong for leads and usually fine for bass.
  • The mistake: boosting with EQ what you should have left in with the filter.

Envelopes: where the character actually is

  • Attack decides whether a sound is percussive or swelling. Anything under 5 ms reads as an immediate hit; over 100 ms it becomes a pad.
  • Decay and sustain together are the shape. Fast decay to zero sustain is a pluck; no decay and full sustain is an organ. This one relationship distinguishes most instrument families.
  • Release is what happens after the note ends. Long release on a bassline is why the low end turns to mud.
  • The filter envelope is the one that matters most in dance music. A fast filter decay over a sustained amp envelope gives you a plucked attack on a held note — that is the sound of almost every house bass ever made.
  • The mistake: shaping with the amp envelope what should have been shaped with the filter envelope. The amp envelope changes loudness; the filter envelope changes timbre over time, and timbre is what your ear reads as an instrument.

Movement: the fifth decision

  • Unison and detune — several copies of the same oscillator slightly apart in pitch. Small amounts (5–12 cents) thicken; large amounts (25–50) become the supersaw. Detune eats mono compatibility, so keep it out of the sub.
  • LFO on cutoff is the wobble, the pulse, the movement in a pad. Slow rates read as evolution, fast rates as texture.
  • LFO on pitch at 4–7 Hz is vibrato; above 20 Hz it becomes FM and changes timbre instead of pitch.
  • Pitch envelope is underrated: a fast drop into the note is a kick, a tom, a zap, and the front of a hoover.
  • The mistake: adding movement to fix a boring patch when the problem was the envelope.
Section 03

Numbers

WaveformHarmonicsReach for it when
SineFundamental onlySub bass, FM carriers, kick bodies
TriangleOdd, falling fastSoft bass, mellow pluck, flute-ish leads
SquareOdd onlyOrgans, garage stabs, hollow leads
SawAll, falling gentlyEverything you plan to filter
NoiseAll, unpitchedHats, risers, transient layers
ResonanceWhat happens
0–2Clean. A filter that just removes.
3–6Character. A bump you hear as "analogue".
7–12Vocal. The sweep becomes the melody.
13–20Acid. The filter rings as its own tone.
20+Self-oscillation territory. Watch your speakers.
DetuneResult
2–5 centsSubtle thickening. Still mono-safe.
6–12 centsClassic two-oscillator width. Most basses.
15–25 centsObvious chorus. Stabs and pads.
25–50 centsSupersaw. Needs 5–7 voices to work.
anyBelow 100 Hz, detune causes cancellation. Keep the sub single-voice.
EnvelopeShapeSounds like
PluckA 2ms · D 120ms · S 0 · R 60msBass, stab, arp
OrganA 5ms · D 0 · S 100% · R 80msDeep house chord
PadA 400ms · D 1s · S 70% · R 1.2sAmbient, breakdown
PercussiveA 1ms · D 60ms · S 0 · R 30msBlip, click, zap
SwellA 900ms · D 0 · S 100% · R 2sRiser, reverse-ish
Section 04

Working rules

Build in this order

  • 1. Waveform. Pick the raw material with the filter wide open, so you hear what you actually have.
  • 2. Filter position. Find the cutoff by ear with the envelope off.
  • 3. Filter envelope. This is where the instrument appears.
  • 4. Amp envelope. Length and gate. Usually shorter than you think.
  • 5. One moving thing. Unison, LFO, or pitch envelope. One, not three.
  • Every recipe on this page follows exactly that order, and you can watch it happen.

Things that are not synthesis

  • A huge amount of what people credit to a patch is effects: saturation, chorus, delay, reverb, and a compressor. A plain saw through a good chain beats a complex patch through nothing.
  • Saturation is the most valuable one. It adds harmonics above the fundamental, which is how a 50 Hz sub becomes audible on a phone.
  • Note length and velocity do more for a bassline than any oscillator choice. That is the previous field guide's argument and it holds here.
  • If the patch only sounds good playing one note, it is not a patch yet — play your actual part while designing.

Where these live in Live

  • Wavetable — closest to this lab. Two oscillators with wavetable positions, sub, noise, two filters, three envelopes, two LFOs. Start here for basses and leads.
  • Operator — four operators, FM. Use it when you want metallic, bell-like or growling tones that subtraction cannot reach.
  • Analog — two oscillators, two filters, simplest routing. Fastest for classic subtractive sounds and it sounds good doing nothing clever.
  • Drift — one oscillator plus a sub, deliberately limited. Excellent for basses precisely because there is nothing to fiddle with.
  • Whichever you pick, learn one properly rather than three badly. The controls are the same controls.

Diagnosis

  • "Thin" — no sub oscillator, or the detune is cancelling the low end. Add a single-voice sine an octave down.
  • "Muddy" — too much sustain, too long a release, or two oscillators at the same octave. Shorten before you EQ.
  • "Boring" — the filter envelope is doing nothing. Set the cutoff low, envelope amount high, decay short, and listen again.
  • "Harsh" — resonance too high with the cutoff in the 2–5 kHz range, which is exactly where ears are most sensitive.
  • "Disappears in the mix" — all the energy is below 200 Hz. Saturate, or add a quiet second oscillator an octave up.

The reason to build rather than browse. A preset teaches you nothing, because you arrive at the end without having seen any of the decisions. Every one of these ten patches is five or six choices made in a fixed order, and once you have watched that order happen a few times you stop needing presets — you hear a sound and know roughly which five decisions produced it.

Everything synthesised live in the browser. The engine is a real subtractive synth with a single filter and simplified FM — it demonstrates the relationships accurately and will not replace Wavetable.