Filters & Modulation
Shape your sound in Draw.Audio with highpass and lowpass filters, filter and pitch ADSR envelopes, and LFOs on 40 synth parameters.
- Highpass Filter
- Thins out the sound by removing low frequencies. Cutoff: frequencies below this are attenuated Resonance: boost at the cutoff point
- Lowpass Filter
- Darkens the sound by removing high frequencies. Cutoff: frequencies above this are attenuated Resonance: boost at the cutoff point
- Filter Graph
- The graph at the top of the Filter panel shows the combined response of both filters, with one node for each cutoff. LFO and automation movement shows on the curve as it plays. Drag a node: left and right sets the cutoff, up and down sets the resonance. Hold Shift for finer steps Scroll over a node: changes the resonance Double-click: resets the nearest node Switch: the switch beside Highpass or Lowpass bypasses that filter
- Filter Envelope
- Sweeps the lowpass cutoff once per note, starting at each note-on. Turn it on with the switch beside Filter Envelope. It has no effect while the lowpass filter is bypassed, and drum tracks do not have it. ADSR: shapes the filter sweep over time Depth: how far and which way the cutoff moves, from −100% to 100%. Positive sweeps up toward 20 kHz, negative sweeps down toward 20 Hz
- Pitch Envelope
- A pitch sweep on each note, found in the Envelope tab of the Oscillator panel. Useful for synth drum hits, laser zaps, or plucks. Drum tracks do not have it. ADSR: shapes the pitch sweep Amount: semitones of pitch bend at peak, from −48 to 48. Negative values bend down
- LFO Overview
- An LFO (low-frequency oscillator) moves a parameter up and down in a repeating cycle. In the LFO tab of the Modulation panel, click Add LFO Target and pick from 40 targets in five groups. Oscillator: pitch, glide, pulse width, wavetable position and warp, FM amount, unison detune, sub osc level, noise level. Filter: lowpass and highpass cutoff and resonance, filter env amount. Amp & envelope: volume, pan, velocity, attack, decay, sustain, release, gate length. Drive & color: warmth (with color and bias), distortion drive, shape, tone and mix, crush rate, ring mod mix and frequency. Effects: stereo spread and detune, chorus rate, depth and mix, delay time and feedback, reverb send. The list offers only what the track can hear: pulse width needs the subtractive synth, FM amount the FM synth, the wavetable targets the wavetable synth, and drum tracks get a shorter list. Attack, decay, release, glide, filter env amount, velocity and gate length are set once as each note starts. Volume and velocity only turn down from their set value. A lane that has no effect, for example because its effect is off, says why and offers a button to fix it. Each lane has an on/off switch and the same controls: Waveform: sine, sawtooth, triangle, or square Rate: 0.01 to 20 Hz, or press Sync to lock it to a note division from 16/1 to 1/32, including 1/4 and 1/8 triplets Depth: how strongly the LFO modulates its target, from 0 to 100 Anchor: restarts the LFO from phase 0 each time you press Play, and when you preview a note while stopped, which keeps the modulation aligned with the beat
- Pitch LFO
- Moves the pitch up and down (vibrato). At full depth the pitch swings one octave each way.
- Highpass LFO
- Moves the highpass cutoff up and down for rhythmic thinning or sweeps on the low end. The cutoff moves in octaves, up to 4 octaves each way at full depth, so a sweep covers the same musical range at any cutoff. No effect while the highpass filter is bypassed.
- Lowpass LFO
- Moves the lowpass cutoff for an auto-wah or filter pulse effect. Like the highpass LFO, it moves in octaves, up to 4 octaves each way at full depth. Raise the lowpass resonance for a sharper sweep.
- Volume LFO (Tremolo)
- Pulses the volume for a tremolo effect. The LFO only turns the volume down from the track's level, never above it. At full depth each dip reaches silence.
- PWM LFO
- Modulates the pulse width of the Pulse waveform, shifting the duty cycle in real time for the shimmering, hollow sound of classic PWM synths. At full depth it sweeps the whole range. Subtractive synth only, and heard only on the Pulse waveform.