Vocoder
Headrush Vocal FX

Vocoder

Inspired by HeadRush® Original

Classic effect that combines:

  • voice (modulator) = shape of sound
  • synthesizer/oscillator (carrier) = stamp

Result: “robotic” voice, synth-voice, digital talkbox

GENERAL FUNCTION

Analyzes the voice into frequency bands.

Apply this “fingerprint” to a synthetic sound.

More bands → more intelligibility.

Control Parameters

Carrier

Select the sound source that is “modelled”

Typical behavior:

  • Internal Osc → internal synth
  • External → instrument (guitar / input)

The carrier determines the character of the sound

Smooth%
  • Range: 0 – 100%
  • Function: smoothing between the vocoder bands

Effect:

  • bass → more defined, robotic sound
  • high → more fluid, less articulated

Reduces artifacts and abrupt transitions

Bands

Number of analysis bands

Behavior:

  • few (8–12): lo-fi / robot
  • medium (16–24): balanced
  • high (24–32+): high intelligibility

more bands = more vocal detail

StereoY/N
  • ON → stereo output
  • OFF → mono

stereo often uses:

  • alternating L/R bands
  • greater breadth
Octave

Carrier shift ± octaves

Effect:

  • −1 → more severe
  • +1 → sharper

Change the vocoder register

Osc Setup

Oscillator configuration

Typical:

  • single osc
  • multi osc/detune

Influences sound thickness

Osc Shape

Waveform:

  • Sine: soft
  • Saw: Brilliant
  • Square: digital
  • Triangle: balanced

Defines the basic tone

Noise%

Adds noise to the carrier

Effect:

  • 0% → clean
  • 20–40% → improved intelligibility
  • high → harsh / industrial effect

Fundamental for understanding consonants (“S”, “T”)

Bright%

Emphasizes high frequencies

Effect:

  • low → dark
  • high → bright / intelligible

Helps “cut into the mix”

Mix%

Blend between original voice and vocoder

  • 0%: dry
  • 50%: parallel
  • 100%: vocoder only
Out BusMain / Alt

Output routing

useful for:

  • separate vocoder and dry vocals
  • FOH processing

Pro Tips

  • Few bands → difficult to understand words
  • Too much noise → dirty sound
  • Too smooth → loss of articulation
  • Wrong carrier → ineffective vocoder

Quick Reference

  • Carriers: sound source
  • Smooth (%): smoothing bands
  • Bands: number of bands
  • Stereo: stereo output
  • Octave: shift hue
  • Osc Setup: oscillator configuration
  • Osc Shape: waveform
  • Noise (%): added noise
  • Bright (%): emphasizes high
  • Mix (%): blend
  • Out Bus: routing

Setup Examples

Classic robot vocoder

Bands16
Smooth30%
Osc ShapeSaw
Noise20%
Mix100%

Daft Punk effect

Intelligible vocoder (pop)

Bands24–32
Smooth50–70%
Noise25–40%
Bright60%
Mix70–100%

Clear and musical voice

Lo-fi / electro

Bands8–12
Smoothlow
OscSquare
Noiselow

Vintage effect

Ambient / cinematic

Bandshigh
Smoothhigh
OscSine/Triangle
Mix50%

Soft texture