A four-head tape delay, eight reverbs and a six-stage phaser — and a feedback loop you can build effects into. Free, open-source, light enough to live on every send.
A real take: heads punch in, the feedback rides up, the reverb flips route, the buffer freezes — audio rendered through the actual engine, knob for knob. Tap Sound to hear it.
It sounds the way it looks — warm, analog, alive. Feedback stays musical right up to self-oscillation, so you can grab the knob and ride it the way a dub engineer rides a send. Saturation, wow and flutter colour every repeat a little more than the last, and the width control opens the echoes wide while your centre image stays put.
Four tape heads, the phaser, a convolution reverb and the full mod matrix — everything switched on — and Doobie still sits around 2–3% CPU. Stack it across every send and bus in your session without watching the meter. Efficient DSP, not a stripped-down feature set.
On hardware you'd re-patch cables to try this. Doobie puts a route switch right on the phaser, the reverb and the pitch shifter — pre, post, or inside the feedback loop — so re-thinking the signal chain is one click, not a rebuild.
always in the path optional route dock — each effect picks pre, post or in feedback
Pick your material — Rhodes keys, a vocal, an acid bassline, a guitar — and hear it through all 79 factory presets: dub springs, tape wobble, shimmer choirs, gated snares. Tap Dry to hear what went in.
Any one of these would be a pedal on its own. Doobie puts them all in one box — and lets them feed each other.
Four heads tap one tape, each with its own level, pan and time, plus ±200 ms of slip for Haas width and off-grid swagger. Synced, heads snap to musical divisions; free, they sit anywhere. Punch them in and out click-free, like channel mutes.
4 heads · A/B/C/D matrixFrom pristine digital to a dying cassette. Tape adds wow, flutter and saturation; BBD goes dark and gluey like a bucket-brigade pedal; Diffuse smears repeats toward reverb; Pitch shifts every repeat by up to ±24 st — climbing octaves, Risset tails, shimmer lines.
Free 0.5 ms–8 s · synced 1/64 to 4 barsA dispersive spring tank for dub, a modulated plate, a dense 16-line hall, shimmer with a selectable interval, spring→plate in series or parallel, convolution with 48 bundled IRs — from York Minster to a nuclear reactor hall (or load your own), and a proper 80s gated plate for that bloom-then-snap snare.
Pre / post / in-feedback routingA classic all-pass cascade with feedback and a stereo offset between channels. Post, it swirls the repeats; pre, the echoes inherit the sweep; inside the loop it deepens with every regeneration until it's a slow, heavy flange.
0.01–8 Hz · stereoSeparate EQ for what goes in and what comes back: the input stage shapes what gets printed to tape, the feedback stage darkens every repeat like oxide wearing off. On top, a resonant multimode filter sweeps from auto-wah to acid squelch — all the way into self-oscillation.
Low-cut · high-cut · bass · trebleTwo LFOs and an envelope follower feed an eight-slot matrix — delay time, head levels and pans, filter cutoff, width, phaser, dozens of targets. Every modulated knob draws its range as an arc with a live dot, so a patch reads at a glance.
2 LFO + envelope · 8 slotsDrive the tape into soft magnetic saturation, add wow and flutter with real random drift, then turn AGE to wear the machine down — hiss, level dropouts, dulling highs, unstable transport. It compounds with every pass through the loop.
Wow · flutter · saturation · ageFlip the pitch shifter or the shimmer into MIDI note mode and play the interval from a keyboard — the delay becomes a harmonizer, the reverb a choir. Pitch bend is always live, and portamento glides between notes over up to two seconds.
AU MusicEffect · pitch bend · glidePing-pong, freeze for infinite holds, a feedback-kill switch for clean chops, and sidechain ducking so the repeats bloom between phrases, not on top of them. An LA-2A-style auto-leveler catches feedback runaway before it clips the bus — push the knob past 100% and stay safe.
Ping-pong · freeze · kill · duckEvery delay character and reverb algorithm, side by side — and each one routes pre, post, or into the feedback loop.
Clean, exact repeats ≈6 dB / repeat, no colour
Wow, flutter, saturation highs fade with every pass
Dark bucket-brigade murk clock noise rises as it dies
One repeat, then a wash ≈2.2 s smear measured
Every repeat shifts, ±24 st an octave up, each pass — measured
Dispersive dub tank tail ≈1.2 s
Dense, modulated sheet tail ≈1.1 s
16-line cathedral bloom tail ≈2.9 s
The tail climbs an interval tail ≈2.8 s
The tank blooms into the sheet tail ≈1.4 s
Both at once, in parallel spring · plate
48 real spaces, or load your own tail = the IR’s
Bloom, hold, then the ’80s snap tail ≈0.4 s
Download a build, or clone and compile it yourself. Doobie is GPLv3 — use it, study it, change it, share it.
VST3, Audio Unit and Standalone. Drop the plug-ins in your Library folder and rescan. macOS will quarantine the download — see the safe steps below.
Latest releaseVST3 and Standalone, built on Ubuntu. Extract into your VST3 path and you're done.
Latest releaseJUCE is vendored as a submodule. One clone, one build.
git clone --recurse-submodules …/doobie
Build instructions
The macOS builds aren’t code-signed with an Apple developer certificate yet, so Gatekeeper quarantines them after download. That’s macOS being cautious about software it can’t verify — not a malware detection. Only bypass it for software you got from a source you trust; for Doobie, that means the official releases page and nowhere else.
xattr -dr com.apple.quarantine ~/Library/Audio/Plug-Ins/VST3/Doobie.vst3 ~/Library/Audio/Plug-Ins/Components/Doobie.component
This removes the quarantine flag from those two bundles only — nothing else on your
system — then rescan plug-ins in your DAW.
Never disable Gatekeeper system-wide (e.g. spctl --master-disable,
a favourite of random forum posts). It protects you from everything else you’ll ever download —
take one known file out of quarantine instead.
Full instructions, changelog and every past version are on the releases page.