Headrush Help Logo
Air Filter
Headrush Wah & Filter

Air Filter

Inspired by AIR® Filter (Plug-in)

Advanced modulated filter (synth filter / auto-wah / filter sweep type) Combina:

  • dynamic filter (LP/HP/BP)
  • LFO modulation
  • harmonic control

GENERAL FUNCTION

Change the audio spectrum using a filter

Can be:

  • static (creative EQ)
  • modulated (auto-wah / synth feel)

Ideal for:

  • electronic effects
  • rhythmic movement
  • sound design

Control Parameters

LFO SyncY/N
  • ON: synced to BPM
  • OFF: free speed in Hz

determines how LFO Rate works

LFO RateHz

Modulation speed

  • slow (0.1–1 Hz) → slow sweep
  • medium (1–5 Hz) → musical movement
  • fast (5+ Hz) → vibrating / synth effect
LFO Depth%

Modulation intensity

  • 0% → static filter
  • medium → natural movement
  • 100% → full sweep
FrequencyHz

Filter center frequency

  • low → dark sound
  • high → bright sound

key point of the stamp

Resonance%

Emphasizes the filter frequency

  • low → soft
  • high → pronounced “peak”.

Create effect:

  • wah
  • synth

Too high → acidic sound

Fatness%

Adds body/saturation on the low end

  • 0% → clean
  • tall → fuller

Useful to avoid sounds that are too thin

Modes

Filter Type:

  • 24 dB: Very steep low-pass (modern, synthetic sound)
  • 18 dB: Medium low-pass (more musical)
  • 12 dB: Soft low-pass (natural)
  • BP (Band Pass): only one band passes (radio/wah effect)
  • HP (High Pass): low size (subtle/shiny effect)
Mix%

Blend between filtered and dry signal

  • 0%: dry
  • 50%: parallel
  • 100%: full effect
GaindB

Output volume

  • compensates for variations

Pro Tips

  • high resonance → risk of aggressive sound
  • depth high → very evident effect
  • HP mode → can lose body
  • high mix → less intelligibility

Creative workflow:

  • choose Mode
  • set Frequency
  • add Resonance
  • then LFO (motion)

Quick Reference

  • LFO Sync: sync tempo
  • Frequency: filter frequency
  • Resonance: emphasis
  • Fatness: body
  • Modes: filter type
  • LFO Rates: speed
  • LFO Depth: intensity
  • Mixes: blend
  • Gain: volume

Setup Examples

Light auto-wah

Mode12 dB
Frequencymedium
Resonance40–60%
LFO Rate1–2 Hz
Depth40–60%

Funky effect

Synth filter (EDM)

Mode24 dB
Resonance70–90%
LFO Ratesync 1/8
Depthhigh

Electronic sound

Ambient movement

Mode12 dB
LFO Rateslow (0.2–0.5 Hz)
Depthmedium

Slow evolution

Band-pass radio

ModeBP
Frequency1–2 kHz
Resonancemedium

Telephone effect