hear it in action

Listen to some audio examples

Envelope Synth

A resonant filter driven by an envelope follower with a touch of warm distortion
Play

Sine FM Showcase

A showcase of what this plugin can do with just a simple sine wave
Play

Metallic Drums

A drum loop with high resonance peak filtering and a hard fold distortion
Play
filtrr is a...ladder
filter
filtrr is a ladder filter, inspired by the classic analog ladder design but with a twist - it is smoothly morphable between lowpass, highpass, bandpass and other shapes!
It is a nonlinear filter, meaning that it can produce unique distortion and saturation in addition to filtering the sound. The nonlinearities in filtrr are inside the feedback path of the filter, making them evolve and change character depending on the input signal, cutoff frequency and resonance settings.
Six nonlinear modes - from simple sigmoid saturation to exotic crunchy folding!
filtrr can be...audio-rate
modulated
filtrr comes with a versatile built-in modulation system that is easy to use.
Modulate the cutoff, resonance, drive, gain, or even the shape with fast LFOs, envelopes, or even audio sidechain!
Please note that the plugin is designed to be pushed to its limits, and extreme modulation or self-resonance can cause very loud output. filtrr has a built-in limiter that is on by default!
filtrr is...clean &
optimized
filtrr uses a fast low-latency oversampling algorithm to reduce aliasing. You have full control over the tradeoff between CPU usage and sound quality. Additionally, filtrr includes intelligent bypass and dynamic update rate for modulation.
Simple to use and intuitive UI, optimized for fast workflow. Minimalistic design. Cute visualizer. Dark and light modes. Freely resizable!

ui overview

Hover over UI elements to read more

Gain Handle

  • Controls the overall filter gain
  • ALT + Click sets it to 0 dB
  • Hold CTRL for precise editing
  • Hold SHIFT or RMB + Drag to control the modulation amount of the gain

Cutoff Handle

  • Drag this to control the cutoff frequency and resonance amount (Q)
  • Hold CTRL for precise editing
  • Hold SHIFT or RMB + Drag to control the modulation amount of the cutoff frequency and Q factor

Main Visualizer

  • Shows the main filter curve (bold)
  • Shows the filter modulation curves (shown when SHIFT or RMB are held or while in Modulation Mode)
  • Also shows the input and output spectra

UI Settings

  • CTRL + Click or Double Click this button to show the UI settings menu
  • Mode. Choose between Dark, Light and Simple color schemes
  • Range. Choose the gain range for the main visualizer/gain handle/cutoff handle
  • Guides. Choose whether you want frequency and gain guides to be shown

Extra Parameters

  • Click this button to show "extra" parameters
  • Limiter. Turn on/off the internal safety limiter that keeps the output from getting too loud
  • Channel. Choose which channels to bypass and which channels to apply the filter to
  • Quality. Choose the internal oversampling quality. Determines the tradeoff between CPU usage and the amount of aliasing
  • Mix. A simple global mix control

Modulation Parameters

  • Available modulation types are: Oscillator (sine, triangle, saw, square), Envelope (input, sidechain), Random (perlin noise), Midi (ADSR, pitch), and Audio (use sidechain input as an audio-rate modulation signal)
  • Hold Mouse Wheel while hovering over "mod" to open the selector menu for fast selection
  • Hold ALT, or use RMB + Drag on the "freq" parameter in "oscillator" mode to sync the frequency to the project tempo

Modulation Mode

  • Click this button to show/hide the internal modulation related parameters

Resize

  • Drag this to make the interface however large or small you want
  • Double click the logo to reset the scale to default

Nonlinearity Mode

  • Choose between 6 unique nonlinear modes, or disable it completely
  • Each nonlinearity has its own unique sound and character
  • Available modes are: Clean, Subtle, Heavy, Warm, Fuzz, Chew and Fold
  • Hold Mouse Wheel to open the selector menu for fast selection

Drive

  • Determines the pre-gain and post-gain applied before and after the nonlinearity
  • Affects the character and sound of the nonlinearity
  • Hold CTRL for precise editing
  • Hold SHIFT, or RMB + Drag to control the modulation amount

Filter Type

  • Controls the filter shape
  • Available types are: Lowpass (6-24 dB/oct), Highpass (6-24 dB/oct), Bandpass, Asym. Bandpass and Peak
  • Hold CTRL to smoothly blend between the shapes
  • Hold SHIFT, or RMB + Drag to control the modulation amount
  • Hold Mouse Wheel to open the selector menu for fast selection