Project
Swayline: AUv3 Chorus
Chorus, doubler, and widener — with a live LFO visualiser
What it is
Swayline is a modulation lab. Six voices — Chorus, Ensemble, Vibrato, MicroShift, Double and Wide — run through a single engine whose shape you sculpt, and everything you set is drawn live on screen. A thin LFO visualiser sits at the top of every view and draws the exact delay voices the DSP is running: one curve for a single tap, two opposing curves for double taps, three staggered curves in Ensemble mode.
Who it’s for
Guitarists, vocalists, and producers on iPhone and iPad who want classic chorus and ensemble movement, natural doubling, or mono-safe stereo width inline in their AUv3 host.
Features
Live modulation strip
A thin LFO visualiser at the top of every view draws the exact delay voices the DSP is running — one curve for a single tap, two opposing curves for double taps, three staggered curves in Ensemble mode.
Six voices
Chorus, Ensemble, Vibrato, MicroShift, Double and Wide run through a single engine whose shape you sculpt.
Double mode
Two detuned copies of the mono sum, each behind its own slowly drifting delay and panned apart, for vocals and guitars without any warble.
Wide mode
A static mid/side widener with a decorrelated mid for mono sources, a side lift up to 6 dB, a side-only high-pass to keep bass centred, and a live correlation readout.
Shaping controls
Rate spans from a 100-second crawl to a 10 Hz flutter, with Amount, Width, Feedback, Warmth, and a high-pass filter for the low end.
Whole-app theming
Selecting a voice re-skins the plugin in that voice's colour: Chorus violet, Ensemble magenta, Vibrato teal, MicroShift periwinkle, Double amber and Wide seafoam.
Works in any AUv3 host
Runs as an Audio Unit extension on iPhone and iPad — AUM, GarageBand, Cubasis, Logic Pro for iPad, Loopy Pro, and other compatible hosts.
Tech
- Swift
- SwiftUI
- C++ DSP kernel
- AUv3 extension architecture
- Real-time audio
- AU parameter automation
- iPhone & iPad
The modulation strip
A thin LFO visualiser sits at the top of every view. It draws the exact delay voices the DSP is running: one curve for a single tap, two opposing curves for double taps, three staggered curves in Ensemble mode. Turn Rate and push Amount and you watch the waveform breathe in real time.
Six voices
Chorus layers a detuned voice into a wide shimmer. Ensemble stacks three staggered voices for the classic string-machine wash. Vibrato goes fully wet — pure pitch warble with no dry signal, for tape wobble and rotary movement. MicroShift applies hairline detune for a pocket stereo widener. Double records the effect of two takes: two detuned copies of the mono sum, each behind its own slowly drifting delay and panned apart, for vocals and guitars without any warble. Wide is a static mid/side widener — no modulation and no pitch movement — with a decorrelated mid for mono sources, a side lift up to 6 dB, a side-only high-pass to keep bass centred, and a live correlation readout. Its mono fold-down always matches the dry signal.
Shaping controls
Rate spans from a 100-second crawl to a 10 Hz flutter on a logarithmic knob. Amount and Width govern depth and stereo spread — Detune, Drift and Spread in Double mode, Mono to Stereo and Width in Wide. Feedback runs through a polarity-invert switch for flanger-leaning tones. Six delay-time voicings, one or two taps, Warmth for gentle analog colour, and a high-pass filter that keeps the low end clean and central.
Whole-app theming
Selecting a voice re-skins the plugin in that voice's colour: Chorus violet, Ensemble magenta, Vibrato teal, MicroShift periwinkle, Double amber and Wide seafoam. Double-tap any knob to reset it, every control is host-automatable, and the compact view keeps the essentials in tight mixer rows. No account, no subscription, no ads.
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