01
Init
All defaults, Sub in Clean mode. A clean pass-through with every module primed — build your own phat chain from here.
Audubon · Plugins
BTN-001
·
v1.0.0
Bass Phattener
Bittern.
The bass-colouring machine.
Bittern is a bass-colouring multi-effect built for heavy dubstep — vintage-voiced Tube and Mech distortion running into a filter with an envelope follower, a Magic EQ, and a glue compressor. It models that classic drive character in closed form, adds one dialled-in LFO wobble engine, and wraps the whole chain in a sub-safety layer most distortion boxes never had.
Under development · v1.1.0
$29
01 — Overview
The boom bird,
for the boom box.
The American Bittern — the "thunder-pumper" — is a marsh bird famous for its booming, sub-frequency call. Fitting, because Bittern is a dedicated bass-phattening chain: drive it, wobble it with a filter, thicken it with a Magic EQ, and glue it with a compressor. Every stage is voiced after the classic bass multi-effects, then wrapped in the Audubon family's sub-safety religion so it can crush and colour heavy bass without ever wrecking the low end.
Vintage-voiced Tube and Mech curves — solved in closed form — with a bass-safety layer most distortion boxes never had.
The two distortion shapers — a warm valve Tube and a hard-knee Mech grit — are defined as exact closed-form curves, continuous to full scale. On top of that sit a bit-crusher, an Aphex-style HF exciter, a TPT state-variable filter driven by an envelope follower and a tempo-synced LFO, a three-band Magic EQ, and a one-knob compressor. A Sub Guard splits the low end off with an LR4 crossover so full-band drive never destroys your sub — and an optional soft-clip ceiling, off by default per the family rule.
02 — The Phat Core
Two authentic curves, plus crush and sheen.
The heart of Bittern is the drive stack — Mech and Tube in series, both defined as exact closed-form curves and continuous to full scale. A bit-crusher and an exciter round out the colour. The whole stack runs inside 4× oversampling.
Mech — Digital Grit
A piecewise-linear hard-knee clipper: linear below the knee, a shallower slope above it. Continuous at the knee but slope-discontinuous — that kink is the "digital grit" that gives Mech its character. Full-scale in maps to full-scale out at every knob position.
Tube — Warm Bite
A linear core with a per-side parabola whose vertex sits exactly at full scale — the warm, biting valve character. Knob 0 is click-free identity; from knob 1 up it matches the original table row-for-row. A Tube-tracked low shelf (+4.5 dB @ 180 Hz at full) adds the low-end fullness for weight.
Crush — Bit Reducer
A bit-depth crusher sweeping from 16 bits down to roughly 2.5 effective bits at 100%. Dubstep grit and digital nastiness on demand — 0% is fully off (clean bypass), so it only bites when you ask.
Xcite — HF Sheen
An Aphex-style biased-tanh exciter on content above 1.2 kHz, generating even + odd harmonics for presence and air. The generated content is high-passed at 400 Hz so it adds sheen up top without muddying the sub — bass-safe by construction.
03 — Sub Guard
Crush the bass. Keep the sub.
Classic full-band distortion drives everything — great on a synth, ruinous on a sub-heavy dubstep bass. Bittern adds a Sub Guard: an LR4 crossover at 120 Hz that decides what happens to the low end while the rest of the signal goes through the full drive chain. It's the family's bass-safety religion, applied to a distortion box.
A — Drive
Full-Band Distortion
The whole signal — sub included — goes through the drive path. The classic full-band behaviour, for when you want the low end saturated too. Use it on synths and mid-heavy bass where a driven sub is part of the sound.
B — Clean
Sub Bypasses Entirely
The default. Everything above 120 Hz is driven and coloured; everything below bypasses the drive chain untouched and is delay-aligned back in. Your sub stays exactly as it came in while the harmonics get mangled on top.
C — Warm
Sub Gets Tube Only
A middle ground: the highs go through the full chain, but the sub receives only the Tube shaper for gentle harmonic weight — no clipping, crush or filtering. Adds valve thickness to the low end without the destructive full-band drive.
04 — The Wobble Engine
A filter that moves.
After the drive stack, the signal hits a TPT state-variable filter — and the filter's cutoff is alive. It can track the input dynamics via an envelope follower and sweep in time with your track via a tempo-synced LFO, both at once. This is the wobble engine, and it's where dubstep bass comes alive.
A — Filter
TPT State-Variable
Four types — LP12, LP24, BP, HP — with Cutoff (20 Hz–20 kHz, log) and Res (Q 0.5–8). Coefficients update per sample and the cutoff is smoothed in the log domain, so even slammed modulation stays stable and click-free.
B — Env
Envelope Follower
An abs-peak detector with Attack (0.1–100 ms) and Release (10–1000 ms) drives the cutoff up to ±4 octaves via the bipolar Env amount. Positive opens the filter on transients for auto-wah snap; negative ducks it. The amber knobs carry this motion.
C — Wobble LFO
Tempo-Synced Sweep
One LFO — Wobble depth (up to 3 octaves) with six shapes (Sine, Tri, Saw Up/Dn, Square, Rand) and 12 tempo divisions from 4 bars down to 1/32 including dotted and triplet. Beat-locked to host transport when playing, free-running at last BPM when stopped.
05 — Magic EQ, Comp & Master
Instant phat, then glue.
Two one-knob finishers voice and control the result, then the master section blends and caps it. Magic EQ is a single macro that voices three bands at once; Comp is a one-knob glue compressor; Master handles Mix, Output and an optional ceiling.
Magic EQ
One Magic knob voices three bands together: a low shelf at Tune (up to +7.5 dB), a mud-scoop dip at 5× Tune (up to −3 dB), and a presence lift at 2.8 kHz (up to +4 dB). Tune (40–160 Hz) sets where the weight lands. Instant "phat" without touching a full EQ.
Compressor
A one-knob 4:1 soft-knee compressor with threshold-tracking auto-makeup — Comp sets the amount, Comp Rel (30–800 ms) the release. Tuned so it lands loud and full like the original, with a cut-only gain-reduction meter. Glue for the whole bass.
Master
Mix (0–100%) blends the whole wet chain against the delay-aligned dry for parallel phattening. Output trims ±24 dB. Soft Clip is an optional tanh ceiling — off by default, per the family rule that true-peak/clip modes never default on.
06 — Controls
Every parameter, grouped.
Twenty-six parameters across five sections. Violet knobs shape tone; amber knobs carry motion and dynamics. Each module has a power toggle that hard-bypasses it with state kept primed, so toggling is click-free.
Input
−24 to +24 dB · def 0
Input trim before the drive stack. Use it to push harder into the Mech and Tube curves or to match gain into the plugin.
Tube
0 – 100% · def 0
The warm-bite valve shaper (exact closed-form curve) with a tracked low shelf for fullness. Click-free identity at 0.
Mech
0 – 100% · def 0
The hard-knee grit shaper (exact closed-form curve). Series after Tube. The slope-kink is the digital-grit character.
Crush
0 – 100% · def 0
Bit-depth reducer, 16 → ~2.5 bits. 0% = off. Digital grit and aliasing for dubstep nastiness.
Xcite
0 – 100% · def 0
Aphex-style HF exciter above 1.2 kHz, generated content HP'd at 400 Hz. Presence and air, bass-safe.
Sub
Drive / Clean / Warm · def Clean
Sub Guard mode (LR4 @ 120 Hz). Drive = full-band; Clean = sub bypasses; Warm = sub gets Tube only.
Filter Type
LP12 / LP24 / BP / HP · def LP12
TPT state-variable filter response. LP24 for steep dubstep sweeps, BP for the "talking" env sound.
Cutoff / Res
20 Hz–20 kHz · Q 0.5–8
Base cutoff (log, def 20 k = open) and resonance (def 15%). The point the env and LFO modulate around.
Env
−100 to +100% · def 0
Bipolar envelope-to-cutoff amount, up to ±4 octaves. Positive = auto-wah open on transients; negative = duck.
Attack / Release
0.1–100 ms · 10–1000 ms
Envelope follower timing (def 5 ms / 120 ms). Fast attack for snap; slower release for smoother movement.
Wobble / Rate
0–100% (0→3 oct) · 4bar…1/32
LFO depth (def 0) and tempo division (def 1/4, 12 options incl. dotted/triplet). Beat-locked to host transport.
Shape
Sine · Tri · SawUp · SawDn · Square · Rand
LFO waveform (def Sine). Square and Rand land click-free thanks to the log-domain cutoff smoother.
Magic / Tune
0–100% · 40–160 Hz
Magic (def 0) voices low shelf + mud dip + presence together; Tune (def 80 Hz) sets where the low weight lands.
Comp / Rel
0–100% · 30–800 ms
One-knob 4:1 glue with threshold-tracking makeup (def 0), release def 150 ms. Cut-only GR meter.
Mix / Output
0–100% · −24 to +24 dB
Dry/wet against the delay-aligned dry (def 100%) and final trim (def 0). Parallel phattening lives here.
Soft Clip
On / Off · def Off
Optional tanh output ceiling. Off by default — the family never defaults a clip/true-peak mode on.
07 — Factory Presets
Ten phat starting points.
Each factory preset resets every parameter to default and then applies its overrides, so it's a clean, reproducible starting point. Save your own as .bitternpreset files.
02
Phat Bass
Moderate Tube, a little Xcite, Magic EQ and light comp. The everyday thicken-and-glue starting patch.
03
Thunder Pump
Heavy Tube with a touch of Mech, strong Magic and comp. Big, booming, pumped — the thunder-pumper itself.
04
Wobble 1/4
Tube drive into a resonant filter with a 1/4-note LFO wobble. The bread-and-butter dubstep sweep.
05
Dotted Growl
Mech and Crush into a resonant filter with a dotted-1/8 LFO. Syncopated, gritty growl movement.
06
Neuro Talk
Mech into a band-pass filter with a fast, deep envelope follower. The "talking", vowel-like neuro sound.
07
Rude Crush
Heavy Crush and Mech with Xcite and comp. Aggressive, lo-fi, digital destruction for rude drops.
08
Warm Sub
Sub Guard in Warm mode with Tube and strong Magic. Adds valve weight to the low end while keeping it solid.
09
Squash & Shine
Light Tube, heavy Xcite, and a hard, slow-release compressor. Squashed, glossy, present — great for reeses.
10
Full Phat
Tube 50 / Mech 50, full-band Sub Drive, soft-clip on. The classic full-band distortion sound, faithfully.
08 — Workflow
How to use it.
01
Set the Sub Guard first. On a sub-heavy dubstep bass, leave Sub in Clean so the low end bypasses the drive chain. On a mid-heavy synth or reese where you want the whole thing coloured, switch to Drive. Warm is the in-between for a little valve weight on the sub.
02
Dial the drive. Push Tube for warm, full saturation or Mech for gritty digital edge — or stack both. Add Crush for lo-fi nastiness and Xcite for top-end presence. Watch the Phat Scope: the violet trace is your driven output against the faint input reference.
03
Bring in the wobble. Set a filter Type (LP24 for classic sweeps, BP for talking neuro), lower the Cutoff and raise Res. Then either raise Wobble with a synced Rate for tempo movement, or raise Env for dynamics-driven auto-wah — or both. The amber knobs are your motion controls.
04
Phatten with Magic EQ. Turn up Magic for instant weight, presence and a cleaned-up mud region, and set Tune to place the low shelf where your bass lives (usually 60–90 Hz). One knob does the work of three bands.
05
Glue with the compressor. Raise Comp until the bass feels solid and even — the auto-makeup keeps it loud and full. Use Comp Rel to set how it breathes: shorter for pump, longer for smoother control. Watch the GR meter.
06
Blend and cap. Use Mix for parallel phattening — keep some dry for punch — and set Output to match bypass. If you need a hard ceiling, enable Soft Clip (it's off by default). Save the result as a user preset.
09 — Specifications
Everything, on one page.
Voicing
Vintage-voiced bass multi-effect — Tube/Mech distortion curves defined in closed form, continuous to full scale
Drive
Mech (hard-knee grit) → Tube (warm bite + tracked low shelf) → Crush (16→~2.5 bit) → Xcite (Aphex HF, HP 400 Hz) · 4× oversampled
Sub Guard
LR4 @ 120 Hz — Drive (full band) / Clean (sub bypass) / Warm (sub = Tube only) · default Clean · delay-aligned
Filter
TPT SVF — LP12 / LP24 / BP / HP · Cutoff 20 Hz–20 kHz · Res Q 0.5–8 · per-sample coeffs, log-smoothed
Envelope
Abs-peak follower · Env ±100% (±4 oct) · Attack 0.1–100 ms · Release 10–1000 ms
LFO (Wobble)
Depth 0–100% (0→3 oct) · 6 shapes · 12 tempo divisions (4 bar…1/32, dotted/triplet) · beat-locked, free-runs when stopped
Magic EQ
One macro · low shelf @ Tune (+7.5 dB) · mud dip @ 5×Tune (−3 dB) · presence @ 2.8 kHz (+4 dB) · Tune 40–160 Hz
Compressor
One-knob 4:1 soft knee · threshold-tracking auto-makeup · Release 30–800 ms · cut-only GR meter
Master
Mix 0–100% (delay-aligned dry) · Output ±24 dB · Soft Clip (tanh) default Off
Parameters
26 total · per-module power toggles (hard bypass, state primed, click-free)
Latency
4× oversampler only (a few samples) · host-reported · dry + sub paths delay-aligned
Format
VST3 · Windows 10 / 11 · macOS 10.13+ (Universal — Apple Silicon & Intel) · 64-bit · window 900×764
MIDI
None — audio effect only (reads host tempo/transport for LFO sync)
Presets
10 factory · user presets saved to Documents (.bitternpreset)
Version
1.1.0
10 — Fine Print
Documentation.
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.
DAW
Any VST3-compatible host — Ableton Live, FL Studio, Bitwig, Reaper, Studio One, Cubase. Insert on any mono or stereo track; built for bass channels. Reads host tempo and transport for LFO sync. VST3 only — Logic Pro and GarageBand load Audio Units, not VST3, so they are not supported.
Latency
A few samples from the 4× oversampler, reported to the host and compensated via PDC. The dry and sub paths are delay-aligned so Mix and Sub Guard stay phase-coherent.
Activation
No iLok, no dongle — activation is offline with the serial from your Members Area. Your download stays accessible in your Members Area.
Personal & Commercial Use
One licence covers all your personal and commercial productions. No royalties, no project restrictions.
Terms & Refunds
See the Terms of Service and Refund Policy for full details.
Original, From-Scratch Design
Bittern is an independent, from-scratch design — its DSP, UI, and presets are our own. It draws on the classic bass-colouring multi-effects for inspiration but is not affiliated with, endorsed by, or derived from any other company or product.
No Redistribution
You may not resell or redistribute the plugin binary. Source code is not included.
v1.1.0 — Update check, from the logo
The Audubon Audio wordmark in Bittern’s header is now a button. Click it and Bittern 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 Bittern 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
Bass-colouring multi-effect for dubstep. Exact closed-form Mech and Tube distortion curves, Crush bit-reducer, Aphex-style Xcite. Sub Guard (LR4 @ 120 Hz: Drive / Clean / Warm). TPT SVF wobble engine with bipolar envelope follower and tempo-synced LFO (6 shapes, 12 divisions). One-knob Magic EQ and glue compressor. Optional Soft Clip (off by default). Live Phat Scope with transfer inset. 10 factory presets. WebView2 UI.
Full User Guide
A step-by-step guide covering the drive stack, the three Sub Guard modes, the envelope + LFO wobble engine, the Magic EQ and compressor, and four workflow recipes (phat bass, dubstep wobble, talking neuro, full-band classic).
Open User Guide →