Vocal Doubler
Headrush Vocal FX

Vocal Doubler

Inspired by HeadRush® Original

Create copies of the entry (from 1 to 32)

Each copy comes lightly:

  • out of tune (pitch)
  • delayed (time)
  • moved into the stereo panorama

Result:

  • voice more wide
  • more thick
  • “studio double tracking” effect

Control Parameters

Pitch Varcents
  • Typical range: 0 – ±50 cents
  • Function: Random pitch variation between voices

Behavior:

  • 0 → all entries identical (useless)
  • 5–10 cents → natural (study)
  • 15–30 cents → noticeable chorus
  • 40+ → detune / dissonant effect

It is the most important parameter for “realism”

Pitch Speed ​​%
  • Function: speed with which the pitch varies over time

Behavior:

  • low → slow variation (natural, human)
  • high → fast variation (chorus/vibrato-like)

Technically it controls an LFO modulation on the pitch

Time Varms
  • Typical range: 0 – ~50 ms
  • Function: random delay between entries

Behavior:

  • 0–5 ms → almost mono
  • 10–25 ms → double realistic
  • 30–50 ms → slap / chorus effect

Simulate the fact that no one sings perfectly in time

Stereo Spread%
  • Range: 0 – 100%
  • Function: stereo opening of the voices
  • 0%: mono
  • 50%: moderate
  • 100%: super wide

Increases the perception of "largeness"

Voices1 / 2 / 4 / 6 / 8 / 12 / 16 / 24 / 32

Number of entries generated

Behavior:

  • 1–2 → realistic double tracking
  • 4–8 → vocal ensemble
  • 12–32 → pad / “choir” effect

More voices = more density but less definition

Lead LeveldB

Original voice volume (dry)

controls how much the main vocal stays in the foreground

Doubler LeveldB

Volume of duplicate entries

  • balance effect vs lead vocal
  • Similar to “wet level” in the plugins
Out BusMain / Alt

Route the output of the doubler

Options:

  • Main → main output
  • Alt → alternative output (separate routing)

Useful for:

  • send only the doubler to FOH/mixer
  • create separate mixes live

(HeadRush allows multiple output routing) (InMusic Brands)

Pro Tips

  • Too many voices → loss of intelligibility
  • Too much pitch var → artificial out of tune
  • Time var high → perceivable delay effect
  • High spread in mono → can lose energy

Quick Reference

  • Pitch Var (cents): pitch variation
  • Pitch Speed ​​(%): pitch modulation speed
  • Time Var (ms): timing variation
  • Stereo Spread (%): stereo width
  • Voices: number of entries
  • Lead Level (dB): dry voice volume
  • Doubler Level (dB): effect volume
  • Out Bus: output routing

Setup Examples

Realistic double tracking (study)

Voices2
Pitch Var5–8 cents
Time Var10–20 ms
Stereo Spread60–80%
Doubler Level−6 dB

Real double recording type effect

Vocal Chorus (modern pop)

Voices4–8
Pitch Var10–20 cents
Pitch SpeedMedium
Time Var15–30 ms
Spreads100%

Wide and brilliant voice

Choir/vocal pad

Voices12–24
Pitch Var15–30 cents
Time Var20–40 ms
Spreads100%
Doubler LevelHigh

“Synthetic choir” effect

Trap / hyperpop

Voices6–12
Pitch Var20–40 cents
Pitch SpeedHigh
Time Var10–25 ms

Glitchy / modern effect