Analysis
Phase-vocoder FFT
2048-point FFT with 4× overlap-add reconstruction. The phase-vocoder approach lets the filter modify magnitude without smearing transients — the analysis hop is small enough that consonants and percussive attacks survive the round-trip cleanly.
Filter
Multiplied-spectrum envelope
Each anchor shape is a frequency-domain envelope; the current shape is a linear interpolation between the two adjacent anchors. The spectrum is multiplied bin-for-bin and inverse-transformed back to time domain. RES controls a per-bin gain curve that sharpens peaks without changing their centre frequencies.
Modulation
Dual-LFO motion engine
Two independent LFOs at related but offset rates feed both MORPH and FREQ, with their phase relationship chosen so the modulation does not repeat predictably. RATE is exponentially curved so the same knob throw covers drift (0.1 Hz) and tremolo (6 Hz) musically.
Shimmer
Octave-up band-limited feedback
A pitch-shifter produces the octave-up harmonic content, then feeds it back into the input with a high-pass at 30 Hz and a low-pass at 6 kHz — the classic Abbey-Road EQ trick. Per-cycle pitch jitter prevents the repeats from stacking into a static drone; instead they chorus naturally.
State
ValueTreeState-backed
Every control is bound to an AudioProcessorValueTreeState. Automation works everywhere, undo/redo is deep, sessions restore exactly how you left them, and the host can ride the MORPH knob through whatever you draw in.
Build
AU · VST3 · Standalone
Universal binary (arm64 + x86_64), targeting macOS 10.13+. Drops in as an insert on any audio or instrument track in Logic Pro, with host-side bypass routing and click-free parameter changes.