---

title: Synths

layout: ../../layouts/MainLayout.astro

---

import { MiniRepl } from '../../docs/MiniRepl';

import { JsDoc } from '../../docs/JsDoc';

# Synths

In addition to the sampling engine, strudel comes with a synthesizer to create sounds on the fly.

## Basic Waveforms

The basic waveforms are `sine`, `sawtooth`, `square` and `triangle`, which can be selected via `sound` (or `s`):

<MiniRepl

  client:idle

  tune={`note("c2 <eb2 <g2 g1>>".fast(2))

.sound("<sawtooth square triangle sine>")

._scope()`}

/>

If you don't set a `sound` but a `note` the default value for `sound` is `triangle`!

## Noise

You can also use noise as a source by setting the waveform to: `white`, `pink` or `brown`. These are different

flavours of noise, here written from hard to soft.

<MiniRepl client:idle tune={`sound("<white pink brown>")._scope()`} />

Here's a more musical example of how to use noise for hihats:

<MiniRepl

  client:idle

  tune={`sound("bd*2,<white pink brown>*8")

.decay(.04).sustain(0)._scope()`}

/>

Some amount of pink noise can also be added to any oscillator by using the `noise` paremeter:

<MiniRepl client:idle tune={`note("c3").noise("<0.1 0.25 0.5>")._scope()`} />

You can also use the `crackle` type to play some subtle noise crackles. You can control noise amount by using the `density` parameter:

<MiniRepl client:idle tune={`s("crackle*4").density("<0.01 0.04 0.2 0.5>".slow(2))._scope()`} />

### Additive Synthesis

To tame the harsh sound of the basic waveforms, we can set the `n` control to limit the overtones of the waveform:

<MiniRepl

  client:idle

  tune={`note("c2 <eb2 <g2 g1>>".fast(2))

.sound("sawtooth")

.n("<32 16 8 4>")

._scope()`}

/>

When the `n` control is used on a basic waveform, it defines the number of harmonic partials the sound is getting.

You can also set `n` directly in mini notation with `sound`:

<MiniRepl

  client:idle

  tune={`note("c2 <eb2 <g2 g1>>".fast(2))

.sound("sawtooth:<32 16 8 4>")

._scope()`}

/>

Note for tidal users: `n` in tidal is synonymous to `note` for synths only.

In strudel, this is not the case, where `n` will always change timbre, be it though different samples or different waveforms.

## Vibrato

### vib

<JsDoc client:idle name="vib" h={0} />

### vibmod

<JsDoc client:idle name="vibmod" h={0} />

## FM Synthesis

FM Synthesis is a technique that changes the frequency of a basic waveform rapidly to alter the timbre.

You can use fm with any of the above waveforms, although the below examples all use the default triangle wave.

### fm

<JsDoc client:idle name="fm" h={0} />

### fmh

<JsDoc client:idle name="fmh" h={0} />

### fmattack

<JsDoc client:idle name="fmattack" h={0} />

### fmdecay

<JsDoc client:idle name="fmdecay" h={0} />

### fmsustain

<JsDoc client:idle name="fmsustain" h={0} />

### fmenv

<JsDoc client:idle name="fmenv" h={0} />

## Wavetable Synthesis

Strudel can also use the sampler to load custom waveforms as a replacement of the default waveforms used by WebAudio for the base synth. A default set of more than 1000 wavetables is accessible by default (coming from the [AKWF](https://www.adventurekid.se/akrt/waveforms/adventure-kid-waveforms/) set). You can also import/use your own. A wavetable is a one-cycle waveform, which is then repeated to create a sound at the desired frequency. It is a classic but very effective synthesis technique.

Any sample preceded by the `wt_` prefix will be loaded as a wavetable. This means that the `loop` argument will be set to `1` by default. You can scan over the wavetable by using `loopBegin` and `loopEnd` as well.

<MiniRepl

  client:idle

  tune={`samples('bubo:waveforms');

note("<[g3,b3,e4]!2 [a3,c3,e4] [b3,d3,f#4]>")

.n("<1 2 3 4 5 6 7 8 9 10>/2").room(0.5).size(0.9)

.s('wt_flute').velocity(0.25).often(n => n.ply(2))

.release(0.125).decay("<0.1 0.25 0.3 0.4>").sustain(0)

.cutoff(2000).cutoff("<1000 2000 4000>").fast(4)

._scope()

`}

/>

## ZZFX

The "Zuper Zmall Zound Zynth" [ZZFX](https://github.com/KilledByAPixel/ZzFX) is also integrated in strudel.

Developed by [Frank Force](https://frankforce.com/), it is a synth and FX engine originally intended to be used for size coding games.

It has 20 parameters in total, here is a snippet that uses all:

<MiniRepl

  client:idle

  tune={`note("c2 eb2 f2 g2") // also supports freq

  .s("{z_sawtooth z_tan z_noise z_sine z_square}%4")

  .zrand(0) // randomization

  // zzfx envelope

  .attack(0.001)

  .decay(0.1)

  .sustain(.8)

  .release(.1)

  // special zzfx params

  .curve(1) // waveshape 1-3

  .slide(0) // +/- pitch slide

  .deltaSlide(0) // +/- pitch slide (?)

  .noise(0) // make it dirty

  .zmod(0) // fm speed

  .zcrush(0) // bit crush 0 - 1

  .zdelay(0) // simple delay

  .pitchJump(0) // +/- pitch change after pitchJumpTime

  .pitchJumpTime(0) // >0 time after pitchJump is applied

  .lfo(0) // >0 resets slide + pitchJump + sets tremolo speed

  .tremolo(0.5) // 0-1 lfo volume modulation amount

  //.duration(.2) // overwrite strudel event duration

  //.gain(1) // change volume

  ._scope() // vizualise waveform (not zzfx related)

`}

/>

Note that you can also combine zzfx with all the other audio fx (next chapter).

Next up: [Audio Effects](/learn/effects)...