ABLETON 12 SOUND DESIGN ATLAS
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Synthesis Primer

Subtractive, FM, wavetable, additive, physical modelling, granular, sampling, phase distortion and west-coast synthesis explained through the Live 12 device that does each, plus envelopes, LFOs, harmonics and aliasing.

synthesissubtractivefmwavetableadditivephysical modellinggranularsamplingphase distortionwest coastbuchlaenvelopeslfoharmonicsaliasingoversampling

Every synth on this site is one of nine ideas about how to make a spectrum move. Once you know which idea a device implements, its front panel stops being a list of knobs and becomes a set of physical decisions: where do the harmonics come from, what removes them, what moves them over time. This page is the vocabulary for everything else here. It is organised by method, each with the Live 12 device that does it, a waveform diagram, and the numbers that matter.

Architecture

Whatever the engine, the signal path of a synthesiser voice is the same skeleton. The methods differ in the first box.

Parameters that matter

Harmonics cheat sheet

WaveformHarmonicsAmplitude lawSounds likeLive device
SineFundamental only—Sub, pure toneOperator, Drift, Meld Swarm Sine
TriangleOdd (1, 3, 5…)1/n²Hollow, soft, flute-ishDrift, Analog (via shape), Wavetable Basics
SquareOdd (1, 3, 5…)1/nHollow but bright, clarinet, chipOperator Square, Analog Rect, Drift Rectangle
SawAll (1, 2, 3…)1/nFull, brassy, the default "synth" soundOperator Saw, Analog, Drift, Wavetable
Pulse 25%All except every 4thVaries with widthNasal, reedy; PWM when movedAnalog Rect PW, Wavetable Classic effect
NoiseContinuous spectrumWhite flat, pink −3 dB/octHiss, snare, airAll synths, Drum Sampler Noise

Envelope stages

StageTypical rangeWhat it controls perceptually
Attack0–20 ms percussive, 50–2000 ms padsClick vs swell; under 2 ms on a sine causes a click
Decay50–800 msHow fast the initial brightness or loudness settles into the body
Sustain0 (pluck) to 1 (organ)Whether the note is a hit or a tone
Release20–100 ms bass, 300–4000 ms padsTail; long releases pile up polyphony and CPU

Techniques

Subtractive: start rich, remove

Devices: Analog, Drift, Wavetable (with Basics tables) · Level: beginner · Genres: all

A bright oscillator (saw, square, pulse) into a resonant low-pass filter whose cutoff is moved by an envelope. The filter is the instrument; the oscillator is just fuel.

  1. Drift: Osc 1 Saw, Osc 2 Rectangle one octave down. Filter MS4 (24 dB), cutoff 300 Hz, resonance 20%.
  2. Route Env 2 to filter cutoff, amount around +40 semitones, Env 2 decay 250 ms, sustain 0.
  3. Add Key tracking 50% so high notes open the filter and low notes stay dark.
A 24 dB/oct slope removes harmonics four times faster than 12 dB per octave above cutoff, so it sounds "fatter" (more low mids survive relative to highs). A 12 dB slope keeps more sparkle and is the Juno/SH character; 24 dB is Moog/Minimoog.
Resonance above about 60% on a 24 dB filter will self-oscillate on MS4 and PRD circuits. That is a sine generator you can play with key tracking at 100%.

FM: one sine bends another

Devices: Operator, Wavetable (FM effect mode), Sampler (Osc FM), Meld FM engine, Granulator III · Level: intermediate · Genres: dubstep, neuro, techno, bells

A modulator oscillator changes the phase of a carrier fast enough to create sidebands. The number of sidebands is set by modulation depth (index); their spacing by the frequency ratio. Integer ratios give harmonic tones, non-integer ratios give bells and metal.

Ratio (mod : car)Result
1:1All harmonics, saw-like; the classic FM bass
2:1Odd harmonics, square-like, hollow
3:1, 4:1Sparse bright harmonics, organ and brass
1.41:1, 3.5:1Inharmonic sidebands, bells, metallic hits
Fixed-frequency modulatorTimbre changes per note; growls and vowels
Bessel functions decide sideband amplitudes, which is why FM brightness does not increase smoothly with index: harmonics come and go. Automating index with an envelope gives the characteristic "wow" as partials fade in and out. See the Operator deep-dive.
FM generates partials above Nyquist very easily. Operator's Tone control and Hi-Q interpolation exist to tame that; Wavetable's FM is oversampled.

Wavetable: scan a sequence of single cycles

Devices: Wavetable · Level: beginner · Genres: bass music, techno, pads

A table holds a set of single-cycle waveforms. Position picks which one plays (with interpolation between neighbours). Modulating position is spectral morphing with no filter involved.

  1. Load Wavetable. Osc 1 category Harmonics, pick a table and drag Position: that is the whole concept.
  2. Open the Mod matrix, LFO 1 → Osc 1 Position at 50%. Sync LFO 1 to 1/8 and you have a wobble with no filter.
  3. Add Filter 1 only to remove what the table adds above 5 kHz.
Because each frame is a stored cycle, wavetables can contain formants, pre-folded shapes and sampled timbres that would need many oscillators to synthesise. Position modulation then moves between them in a way filters cannot.

Additive: draw the harmonics

Devices: Operator (user waveform), Wavetable Harmonics tables, Meld Swarm Sine · Level: intermediate · Genres: ambient, organ, bells

Build the spectrum directly by setting the level of each partial. Operator's user waveform mode lets you draw up to 64 harmonic amplitudes per oscillator; the Repeat parameter tiles the pattern.

Drawing only odd partials with a 1/n² law gives a triangle. Drawing partials 1, 2, 4, 8 gives an organ-ish octave stack. Drawing partials 1 and 7 gives something like a bell without any FM.
Additive is the only method where the spectrum is explicitly specified; everything else derives it. The weakness is that each partial is static per oscillator, so dynamics must come from envelopes, filters or FM on top.

Physical modelling: excite a resonator

Devices: Collision, Tension, Electric, Corpus, Resonators, Spectral Resonator · Level: intermediate · Genres: ambient, trip-hop, percussion

Simulate the object: an exciter (mallet strike, noise burst, bow) injects energy into a resonator (string, beam, plate, membrane, tube) whose modes ring down. Velocity changes the physics, not just the volume.

  1. Collision: Mallet on, Volume 70%, Stiffness 55%, Noise Amount 15%, Color 50%. Resonator 1 type Marimba, Decay 1.5 s, Material 0.3.
  2. Turn Resonator 2 on, Plate, Decay 4 s, pan it opposite. Set Resonator 2 input from Resonator 1 for a serial ring.
  3. Collision's Inharmonic parameter stretches the mode ratios: 0 = tuned, 1 = metallic clang.
A resonator is a bank of band-pass filters whose centre frequencies are the object's modes. That is why Corpus and Resonators work on any audio: a drum through Corpus is literally a drum hitting a marimba bar.

Granular: thousands of tiny samples

Devices: Granulator III, Grain Delay, Simpler (Texture/Complex warp), Sampler · Level: intermediate · Genres: ambient, idm, dubstep textures

Chop a sample into grains of 5–200 ms, window each one, and play them back at any position, pitch, density and spread. Long grains sound like the source; short grains become tone.

ParameterRangeEffect
Grain size5–30 msPitched buzz at 1/size Hz; 10 ms = 100 Hz tone
Grain size50–200 msRecognisable source, smeared
Spray / scan0–100%Position randomness; width of the cloud
Density / overlap1–16Thickness; more grains = more CPU and more smear
Grain rate is a frequency. At 20 grains per second you hear rhythm; above 30 per second it fuses into a pitch. Granular is pitch-shifting, time-stretching and synthesis at once because it decouples all three.

Sampling: the recording is the oscillator

Devices: Simpler, Sampler, Drum Sampler, Drum Rack, Impulse · Level: beginner · Genres: all

Any recorded sound becomes a voice. The synthesis happens in the warp mode, the filter, the envelope and in resampling the result. Live 12.3 stem separation adds extraction to this.

Transposing a sample without warp (warp off) shifts formants with pitch: that is the classic jungle chipmunk and the slowed-down phonk vocal. Warp on with Complex Pro keeps formants. Both are tools.
A sample has a fixed spectrum and envelope. Everything you do afterwards (filter, FM in Sampler, grains in Simpler's Texture mode) is one of the other methods applied to it.

Phase distortion: warp the read pointer

Devices: Wavetable (Modern effect: Warp), Operator (approximated with feedback), Meld · Level: advanced · Genres: synthwave, idm

The Casio CZ idea: read a sine with a non-linear phase ramp. Bending the ramp squeezes half the cycle, which adds harmonics the way a resonant filter sweep does, without a filter.

Phase distortion and wavefolding are both waveshaping: a static mapping from input to output. Their harmonics scale with input level, so velocity → amount gives natural dynamics.

West-coast: fold a simple wave, then shape with lowpass gates

Devices: Saturator (Sinoid Fold), Roar (Fold shaper), Wavetable Modern (Fold), Meld, plus your Buchla 258t clone via External Instrument · Level: advanced · Genres: ambient, idm, techno

Instead of subtracting from a rich wave, start with a sine or triangle and add harmonics by folding it back on itself. Dynamics come from a lowpass gate (a filter and VCA in one, with vactrol-style decay) rather than ADSR. Your 258t is a dual oscillator with sine-to-saw / sine-to-square morphing — the ideal fuel for a folder.

  1. Send the 258t's sine into Live. Add Saturator, shape Sinoid Fold, Drive 6 dB. Automate Drive 0 → 18 dB: that is a timbre sweep with no filter.
  2. Instead of an amp envelope, use Auto Filter LP 12 dB with its envelope follower on the input, or Roar's envelope-follower-to-filter route. The cutoff drops with amplitude, which is what a lowpass gate does.
  3. For a fully in-the-box version: Wavetable Basics triangle, Effect Modern, Fold driven by Env 3, into Filter 1 Clean LP 12 dB with Env 3 also on cutoff.
Folding adds harmonics in proportion to input level, like the "timbre" knob on a 259. Because the sine is band-limited and the fold is symmetrical, you get mostly odd harmonics; add a little DC or asymmetry (Saturator DC) to get even harmonics and a brassier tone.

Aliasing and oversampling

Devices: all; especially Operator, Roar, Saturator, Redux · Level: intermediate

Any process that creates harmonics above half the sample rate (22.05 kHz at 44.1 k) folds them back down as inharmonic partials. Sometimes you want that (Redux, Erosion, Operator with Tone up on a growl); usually you do not.

DeviceHow it handles it
OperatorTone control attenuates high partials in waveforms; Hi-Q interpolation reduces aliasing in the oscillators
Saturator, RoarInternal oversampling; Saturator's Hi-Q option trades CPU for cleanliness
Wavetable, Drift, MeldBand-limited oscillators; aliasing only appears with extreme FM or fold
Redux, Erosion, Vinyl DistortionAliasing is the point; use them when you want digital hash
Hear aliasing: play a high note on Operator with Tone at 100% and a Saw waveform, then sweep pitch. Partials that move down while the pitch goes up are aliases.

Modulation basics

An LFO is an oscillator too slow to hear. Below about 20 Hz it is movement; above it, it becomes timbre (which is what FM is). Live's modulation layer: every synth has at least one envelope and LFO; Wavetable and Meld add matrices; the Max for Live LFO, Envelope Follower and Shaper modulate anything, including effect parameters and macros.

ModulationRateUse
Vibrato4–7 Hz, ±10–30 centsLeads, with delay 200 ms so the note starts straight
WobbleSynced 1/4 to 1/16Filter or wavetable position
Drift0.05–0.5 Hz, randomAnalogue instability on pitch or cutoff
Audio-rate20 Hz+FM, AM, ring modulation; Operator and Meld do this natively

Presets to build first

  1. Drift subtractive bass: saw + sub rectangle, MS4, filter envelope decay 200 ms.
  2. Operator 1:1 FM bass with modulator level driven by velocity.
  3. Wavetable formant pad with LFO 1 on position, Unison Shimmer.
  4. Collision marimba with Resonator 2 plate for a trip-hop mallet.
  5. Saturator Sinoid Fold on a sine from your 258t, recorded and resampled into Simpler.

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