1
Boost
A transparent clean-blend boost stage modeled on the mythical gold boost pedal — it lifts and firms without smearing the transient. At 0 it is a hard bypass.
Audubon · Plugins
CSW-001
·
v1.0.0
Ultra Overdrive
Cassowary.
The world's most dangerous overdrive.
The world's most dangerous bird gets the world's most dangerous overdrive. Five circuit-modeled drive voices — two generations of the legendary green screamer circuit, a hard-clip rodent-style stage, a two-stage cascade fuzz and a warm low-gain valve stage — plus a STACK slot that runs any voice into any voice, behind a transparent clean-blend boost and in front of a transformer output stage. All of it wrapped in an LR4 Sub Guard, so the claw only ever comes down on the top end.
Under development · v1.1.0
$19
01 — Overview
A pedal chain, circuit-modeled.
Cassowary is not a curve you draw or a shape you pick from a list — it is a modeled analog chain, in order: a transparent boost, a drive stage with five circuit voices, a stackable second drive stage, a three-band tone section, and a transformer output stage. A Linkwitz-Riley Sub Guard splits the sub out before any of it and folds it back in clean, so a bass patch keeps its weight no matter how hard the top is pushed.
The centre of the interface is THE CLAW — a live transfer-curve display. The curve you see is the drive law you have dialed in, with the input and output level riding it as a ball, and a heat glow that blooms with the drive amount as signal passes through. Nothing on screen is decoration: it is the shape the audio is actually being pushed through.
Every colour stage is honest about doing nothing. BOOST at 0 and IRON at 0 are hard bypasses, not near-unity settings. TILT at centre is an exact identity. DYN at 0 is a factor of exactly one. MIX is a phase-aligned dry blend with no latency to compensate. Turn on only the parts the track needs.
02 — The Engine
Solved as a circuit, not sampled as a shape.
The clipper at the heart of Cassowary is a wave digital filter — the diode network is solved per sample, with its real feedback capacitance, so the knee, the recovery and the level dependence behave the way the circuit does rather than the way a static curve does.
Wave Digital Diode Clipper
The clipping stage is a wave-digital model of a real diode feedback network, evaluated sample by sample. Bounded no matter what you feed it, and asymmetric the way a biased circuit is — not the way a lookup table is.
Zero Reported Latency
The whole chain — boost, drive, tone, transformer, Sub Guard and dry blend — reports zero latency to the host. The dry path for MIX is time-aligned, so blending never combs.
Zero-Latency Oversampling
Off, 4× standard or 8× HQ, applied to the boost, drive and transformer cores, with no reported latency at any setting. 4× is the default; go to 8× when you are pushing extreme drive into bright material.
THE CLAW
The hero display draws the live transfer curve with the signal riding it, and glows hotter as drive rises. You can see the asymmetry BIAS adds and the way DYN moves the curve with your playing.
03 — The Chain
Five stages. In pedalboard order.
Signal above the Sub Guard crossover runs boost into drive into stack into tone into iron — the same order you would build it on the floor, with the colour stages hard-bypassed until you turn them up.
2
Drive
The overdrive itself: CLASSIC, ULTRA, TALON, FUZZ or VELVET — five circuit voices, with BIAS for asymmetry and DYN for envelope-tracked gain.
3
Stack
A full second drive stage: any of the five voices with its own DRIVE B, run after stage A — two pedals in series, in one box. OFF is a hard bypass.
4
Tone
TILT tips the balance dark-to-bright around the clipped signal, BODY is a 250 Hz shelf and PRESENCE a 3 kHz shelf. All three rest at centre, doing nothing.
5
Iron
A hysteresis-modeled transformer output stage. ALLOY morphs the core from clean iron to coloured nickel; IRON at 0 is a hard bypass.
04 — The Voices
Five circuits. Stack any two.
Every voice is a modeled circuit with its own gain structure and its own knee — and the STACK row underneath THE CLAW runs a second one after the first, the way players have chained drive pedals forever. Five voices, five stack partners, one BOOST in front and one transformer behind: that is 25 stacked drive laws before you touch a tone control.
A — Classic
The Dynamic Voice
A living model: bias drifts under sustained level the way a blocking-distortion stage does, the harmonic content changes with how loud you hit it, and the mids and highs are driven separately. Its mid hump sits at 980 Hz, +7.2 dB.
B — Ultra
The Authentic Three-Stage Voice
The default. A 30 Hz coupling high-pass into a 720 Hz Q1.5 mid hump at +6 dB, a hard ×41 drive, and three cascaded wave-digital diode clipper stages. The tearout voice.
C — Talon
The Hard Clip
A rodent-style hard clipper: a rising-treble gain stage into a silicon pair on a tight 1 kΩ source, so the knee lands late and bites hard — clean right up until it suddenly is not — with a fixed post filter to keep the fizz civilised. The neuro mid-grind voice.
D — Fuzz
The Wall
Two cascaded gain-into-clip stages, big-box style: the second stage re-clips the first stage's already-flattened output into a proper wall. No baked-in mid scoop — on a bass bus it still cuts; if you want the scoop, TILT is right there.
E — Velvet
The Warm One
A low-gain valve-style stage biased warm on purpose: second-harmonic colour is there even at zero drive, and the gain ceiling is modest, so it thickens instead of tearing. Beautiful alone on a Reese bed — and the natural stack partner for rounding off anything placed before it.
F — The Stack
Two Pedals, One Box
The STACK row loads any voice as a second stage with its own DRIVE B — stage A runs into stage B in series, exactly like chaining pedals. Push a screamer into the hard clip to tighten it, or land anything on VELVET to round it off. OFF is a true hard bypass.
G — Bias & Dyn
Global Character
BIAS offsets the signal into every clipper — centred it is symmetric and odd-harmonic, moved it brings even harmonics up. DYN is an envelope follower (1 ms attack, 30 ms release) that scales drive with your playing. Both feed stage A and the stack alike; at rest both are exact no-ops.
05 — Sub Guard
Maul the top. Leave the sub alone.
A — LR4 Crossover
Only the Band Above Gets Driven
A 4th-order Linkwitz-Riley crossover splits the input before the pedals. Only the high band sees boost, drive, tone and iron; the low band is carried around all of it and summed back untouched.
B — Sub X
60 – 300 Hz, Log
Set the split right above your fundamental — 120 Hz by default — so the harmonics get mangled and the weight underneath does not.
C — Sub Level
Up to 125 % Back Into the Sum
The clean sub returns at unity by default, and can be pushed a little past it when a heavily driven top needs more anchor underneath.
D — Sub Mono
Mono Below the Split, On by Default
Folds only the protected low lane to mono — the dubstep default, on out of the box. Club rigs are mono down low; the top of the sound keeps every bit of the width you gave it.
06 — Controls
Thirteen knobs, five switches.
Boost, drive and iron set the colour; tilt, body and presence shape it; the Sub Guard protects the bottom; mix, level and the utility switches finish the job.
Boost
0 → 100 % · def 0
The clean-blend boost stage. At 0 it is hard-bypassed, so the stage cannot colour anything until you ask it to.
Drive
0 → 100 % · def 35 %
How hard stage A's voice is pushed. The one knob that decides whether this is warmth or damage.
Drive B
0 → 100 % · def 35 %
The stack stage's own drive. Lives in the STACK row, and dims until a stack voice is loaded.
Bias
0 → 100 % · centre 50 %
Pre-clipper offset. Centre is symmetric and odd-harmonic; away from centre brings in even harmonics.
Dyn
0 → 100 % · def 0
Envelope-tracked drive from a 1 ms / 30 ms peak follower. Exactly no-op at 0.
Tilt
0 → 100 % · centre 50 %
Tips the clipped signal dark or bright. Centre passes the clipped signal through exactly.
Body
±6 dB @ 250 Hz
Low shelf on the driven band — put the chest back in after the clipper thins it, or take out the honk.
Presence
±5 dB @ 3 kHz
High shelf on the driven band, for the bite that cuts through a busy mid range.
Iron
0 → 100 % · def 0
Drive into the transformer output stage. Hard-bypassed at 0.
Alloy
0 → 100 % · def 35 %
Morphs the transformer core from clean iron toward coloured nickel — more even harmonics, more high-frequency saturation.
Sub X
60 → 300 Hz · def 120 Hz
The Sub Guard crossover point. Everything below it bypasses the whole pedal chain.
Sub
0 → 125 % · def 100 %
How much of the clean, protected low band comes back into the sum.
Mix
0 → 100 % · def 100 %
Phase-aligned dry blend with no latency to compensate. At 0 the output is the dry signal.
Level
−24 → +24 dB
Output trim, for level-matched comparisons against bypass.
Voice
Classic / Ultra / Talon / Fuzz / Velvet · def Ultra
Picks stage A's circuit: dynamic screamer, three-stage screamer, hard clip, cascade fuzz or warm valve stage.
Stack
Off / any voice · def Off
Loads a second drive stage after stage A — same five circuits, its own Drive B. Off is a true hard bypass.
OS
Off / 4× / 8× · def 4×
Oversampling for the boost, drive and transformer cores. Higher settings buy cleaner top end at extreme drive.
Sub Mono
On / Off · def On
Folds only the protected low lane to mono. On by default, because bass music wants it that way.
Auto Gain
On / Off · def Off
RMS level matching across the drive range, clamped to ±18 dB. Off by default so nothing touches your level unasked.
Delta
On / Off · def Off
Monitors wet minus dry — exactly what Cassowary is adding, and proof that the sub is not in it.
07 — Workflow
From insert to damage, in six moves.
01
Insert Cassowary on a bass, a mid growl or a drum bus. Sub Guard is already active with Sub Mono on — the low end is protected from the first knob turn.
02
Set Sub X just above your fundamental, around 120 Hz, so only the harmonics go into the chain.
03
Choose a voice — ULTRA for aggression, TALON for hard grind, FUZZ for the wall, VELVET for warmth, CLASSIC when you want the drive to breathe with the part — and bring DRIVE up until it bites.
04
Want more? Load a second voice in the STACK row and set DRIVE B — a screamer into TALON tightens it, anything into VELVET rounds it off. Then push DYN so loud passages break up harder, and shift BIAS off centre for even-harmonic thickness.
05
Shape it with TILT, BODY and PRESENCE, add BOOST in front for a cleaner, firmer lift, and dial IRON with ALLOY for transformer weight at the end.
06
Blend with MIX, trim LEVEL, hit DELTA to hear exactly what you are adding, and raise OS only if extreme drive needs a cleaner top end.
08 — Specifications
Everything, on one page.
Format
VST3
Category
Fx · Distortion / Overdrive
Platform
Windows 10 / 11 · macOS 10.13+ (Universal — Apple Silicon & Intel) · 64-bit
Version
1.1.0
Signal chain
Sub Guard split → Boost → Drive A → Stack B → Tone → Iron → sum → Auto Gain → Mix → Level → Delta
Voices
Classic (dynamic, 980 Hz / +7.2 dB mid hump) · Ultra (three-stage, 720 Hz Q1.5 / +6 dB mid hump, default) · Talon (hard clip, 1 kΩ silicon pair, fixed post filter) · Fuzz (two cascaded clip stages) · Velvet (low-gain valve-style, second-harmonic warmth)
Stack
Second full drive stage — any voice with its own Drive B, in series after stage A · 25 combinations · hard bypass when off
Clipper
Wave digital filter diode network, per-sample, bounded output
Boost
Transparent clean-blend boost stage, hard bypass at 0
Bias
Pre-clipper offset — odd harmonics at centre, even harmonics away from it
Dyn
Envelope-tracked drive, 1 ms attack / 30 ms release peak follower, exact no-op at 0
Tone
Tilt (exact identity at centre) · Body shelf 250 Hz ±6 dB · Presence shelf 3 kHz ±5 dB
Iron / Alloy
Hysteresis-modeled transformer output stage, iron → nickel core morph, hard bypass at 0
Sub Guard
4th-order Linkwitz-Riley crossover, 60 – 300 Hz (default 120 Hz), clean low band summed back at 0 – 125 %
Sub Mono
Folds only the protected low lane to (L+R)/2 · on by default
Oversampling
Off · 4× · 8×, default 4×, on the boost, drive and transformer cores · zero reported latency
Auto Gain
RMS match, ±18 dB clamp · off by default
Delta Monitor
Listen to wet minus dry — exactly what Cassowary adds
Mix / Level
0 – 100 % phase-aligned dry blend · −24 to +24 dB output trim
Presets
18 factory presets, bass-first
Latency
Zero reported latency
State save
Full settings saved with DAW project
09 — Fine Print
Documentation.
DAW
Any VST3-compatible host — Ableton Live 11+, FL Studio 20+, Reaper, Cubase, Studio One, Bitwig, and others. VST3 only — Logic Pro and GarageBand load Audio Units, not VST3, so they are not supported.
Operating System
Windows 10 or 11 (64-bit) — the editor uses WebView2, which is built into Windows 11 and most current Windows 10 installs. macOS 10.13 High Sierra or later — one Universal build runs natively on both Apple Silicon and Intel Macs.
Format
VST3 effect. Insert on any mono or stereo channel that needs analog-style overdrive without losing its low end.
Latency
Zero reported latency, with the dry blend time-aligned so Mix never combs.
Recommended Setup
Start on the ULTRA voice with Drive around 35 %, Sub X at 120 Hz and Sub Mono on. Then add DYN for movement, BIAS for even harmonics, and IRON for weight.
Updates
First release 1.0.0. Free updates for all future 1.x releases.
v1.1.0 — Update check, from the logo
The Audubon Audio wordmark in Cassowary’s header is now a button. Click it and Cassowary asks audubonaudio.com one question — which build is current — then shows that number beside the one you are running, with a link straight to the members area if there is something newer and a plain “you have the current version” if there is not. If it cannot reach us it says so rather than claiming you are up to date. This is the only moment Cassowary touches the internet, it happens only on that click, and nothing about you goes with it — no serial, no licence, no machine id, not even your version or operating system. The comparison happens on your own machine.
v1.0.0 — Initial Release
First release. Five circuit-modeled drive voices — Classic (dynamic), Ultra (three-stage), Talon (hard clip), Fuzz (two-stage cascade) and Velvet (low-gain valve warmth) — on wave digital filter diode clippers, plus a Stack slot that runs any second voice in series with its own Drive B. A transparent clean-blend boost stage, a Tilt / Body / Presence tone section, a hysteresis-modeled transformer output stage with iron-to-nickel Alloy morph, an LR4 Sub Guard with Sub Mono, envelope-tracked Dyn drive, Off / 4× / 8× oversampling, Auto Gain, Delta monitoring, phase-aligned Mix, and 18 factory presets.
Full User Guide
A step-by-step walkthrough of the five voices, the Stack, the Sub Guard, the tone section and the transformer stage — plus workflow recipes for bass and dubstep mids — publishes here with the 1.0.0 release.
Personal & Commercial Use
Use Cassowary in any project — music production, mixing, sound design, post-production, broadcast, and live performance. No royalties, no project restrictions.
Single User
One license per user. Install on the computers you personally own or operate.
Serial Activation
Your license includes a unique serial number tied to your email. Your serial and download are permanently accessible in your Members Area.
Free Updates
All 1.x updates are free. Your serial activates the current version and all future updates in the 1.x line.
No Redistribution
The plugin binaries may not be shared, resold, or redistributed. Each user must obtain their own license.