Bandlimited oscillator
Saw and square with glide, tuned for bass. No aliasing folds on high notes, because the oscillator is bandlimited rather than naïvely sampled.
VST3 + standalone · Windows x64 · free download
G- ACID BASE A Goa trance acid bass synthesizer. 303 reimagined.
One bandlimited oscillator into a nonlinear resonant ladder filter, with the two gestures that define the sound — accent and slide — and a 16-step sequencer that carries gate, accent and slide per step. 4x oversampling keeps the resonance from aliasing when the cutoff is wide open, and 50 factory presets get you to a squelch before you touch a knob.
- 50factory presets
- 16sequencer steps
- 4xoversampling
- v1.1.1current release
Sound
Original 303-inspired synthesis, not a circuit emulation
The signal path is deliberately small: one oscillator, one filter, one amp, and the accent and slide gestures that make an acid line move. Everything else in the window is there to bend that path.
Nonlinear resonant ladder
A resonant ladder filter with the resonance the genre is built on, and a nonlinear stage that gives it the squelch rather than a clean biquad slope.
Accent and slide
Per-step accent and slide, the two 303 gestures that separate a line that breathes from one that just plays notes. Accent hits the filter and the amp together.
4x oversampling
The filter and distortion run oversampled with JUCE polyphase IIR half-band filters, and the reported latency is an integer number of samples, so a host can compensate.
Four distortion colours
A distortion panel with four characters for pushing the filter into the room, from a gentle saturation to a full-on squashed acid tone.
Space and movement
Reverb with predelay and diffusion, a tempo-synced ping-pong delay with filtered feedback, tone shaping and stereo movement — each on its own page in the FX panel.
Sequencer
16 steps, each with its own gate, accent and slide
The sequencer is the instrument. Every step carries a pitch, a gate, an accent and a slide flag, and the pattern banks let you keep several lines around and chain them into a longer arrangement.
- Per-step probability — a step can play, or not, on any given pass.
- Ratchets — subdivide a step into repeats without leaving the grid.
- Microtiming — nudge a step early or late against the grid for swing.
- Pattern banks and chains — hold patterns in banks and chain them with repeat counts.
- Host tempo and PPQ — when the host is playing, the sequence follows its transport.
Performance
Made to be played, automated and learned
MIDI CC learn
Right-click any continuous control to bind a MIDI CC. Pickup and two relative encoder modes cover both kinds of hardware controller, and the mappings are remembered.
Macros and morphing
Assign parameters to macros, capture two states of the whole instrument and morph between them — the pattern you sketch becomes something you can sweep.
LFOs and a mod matrix
LFOs and a MIDI modulation matrix for movement that stays in time, including mod wheel vibrato and CC1-style expression.
Undo, redo, A/B
Undo and redo across edits, plus A/B compare with a store action, so a tweak you regret is one shortcut away from being undone.
MIDI export
Export the pattern as a MIDI file and drag it straight out of the plugin into your DAW's timeline.
Animated header
The mark beside the plugin name runs one cycle per beat of host tempo, and opens up with the resonance control — a small thing that tells you the transport is live.
Screens
The pages behind the panels
Download
Install G-AcidBase for Windows
The installer puts the VST3 instrument and the standalone app where your DAW looks for them, and removes them again. Prefer to place the files yourself? The same ZIP holds the plugin folder. Nothing to activate, no account, no phone-home.
Download 1.1.1ZIP package·Installer·SHA-256 checksums·all files
- Run
G-AcidBase-Setup-<version>.exeand press INSTALL. It puts the plugin in the standard VST3 folder every DAW scans (Windows asks for administrator permission once) and the standalone app beside it. Prefer no administrator rights? Choose Custom folder and pick%LOCALAPPDATA%\Programs\Common\VST3\if your DAW scans that user location. UNINSTALL, or--silent <folder>with no window at all, are both there. - Or unzip
G-AcidBase-Windows-x64.zipand copyG-AcidBase.vst3into%LOCALAPPDATA%\Programs\Common\VST3\, or add the unzipped folder to your DAW's VST3 scan paths. The machine-wide location isC:\Program Files\Common Files\VST3\, which needs administrator permission. - Rescan plugins and load G-AcidBase as an instrument on a MIDI track — it is a synth, not an audio effect.
- Start with low monitor volume. Choose one of the 50 presets, or send note C2 (MIDI 36) and turn the cutoff down.
Every file in the archive is listed with its own SHA-256 in G-AcidBase/manifest.json,
and the archive also carries the verification reports the build produced. The published
SHA256SUMS.txt on the release is what the downloaded installer and ZIP are checked against.
Release notes
Change Log
What's changed in each G-AcidBase release. Version links open the same notes linked by the plugin's update dialog.
Version 1.1.1
- Added A Windows installer, G-AcidBase-Setup-1.1.1.exe: it puts the plugin and the standalone app where DAWs look for them - the standard VST3 folder every host scans (Windows asks for administrator permission once) or any custom folder - adds an Add/Remove-Programs entry, installs with no window at all through --silent <folder>, and removes everything again through --uninstall.
- Added The plugin checks for a new release by itself, once per session, on the first window opening. It stays silent unless a newer version is really available, so an unreachable feed and an up-to-date build say nothing; CHECK FOR UPDATES by hand still always answers, and reopening the window never repeats the automatic request.
- Added TOOLS → CHANGE LOG opens the full release history on the product site, and the up-to-date dialog links the running version's notes.
- Changed The update dialog's download link now goes straight to the new version's installer instead of the package, and the size it quotes is the installer's.
- Changed The product page's release notes and download section are generated from this changelog and the release's assets, so they name the package, the installer and the published checksums without anyone pasting links by hand.
Download 1.1.1ZIP package·Installer·SHA-256 checksums·all files
Version 1.1.0
- Fixed Sequencer transport fixed: RUN is the sequencer's play button - it starts the sequence from any play mode, browsing the 50 presets keeps it running, and choosing MIDI play mode stops it.
- Added Animated header mark: the logo beside the plugin name runs one cycle per beat of host tempo, swells on the beat and opens up with the resonance control.
- Added Pattern banks and repeatable chains: hold several lines in banks and chain them with per-entry repeat counts.
- Added Probability, ratchets and microtiming per step, so a line can breathe without leaving the 16-step grid.
- Added Macros with morphing, a MIDI modulation matrix, and controller pickup plus two relative encoder modes.
- Added MIDI CC learn by right-click on any continuous control, and MIDI file export with drag-out to the DAW.
Specifications
What is in the box
- Format
- VST3 (instrument / synth) and standalone
- Platform
- Windows 64-bit
- Presets
- 50 factory patterns, numbered 01–50
- Oscillator
- Bandlimited saw and square with glide
- Filter
- Nonlinear resonant ladder with accent and slide
- Oversampling
- 4x, polyphase IIR half-band, integer reported latency
- Sequencer
- 16 steps × pitch / gate / accent / slide, probability, ratchets, microtiming
- Patterns
- Banks and chains with per-entry repeat counts
- Modulation
- LFOs, MIDI mod matrix, macros with morphing
- Controllers
- MIDI CC learn by right-click, pickup and two relative encoder modes
- Editing
- Undo / redo, A/B compare with store
- MIDI
- Pattern export to a MIDI file with drag-out to the DAW
- Requirements
- 64-bit Windows and a VST3 host
- Licence
- JUCE modules are dual-licensed AGPLv3 or a commercial JUCE licence — see the notes in the source repository
Source and verification
Built in the open, checked before it ships
The repository holds the engine, the editor, the test suite, the logo generator and the release packager. CMake fetches JUCE at a pinned commit, so a clean checkout builds the same thing the release contains.
Two test suites
A 50-preset render and audio check, and a feature suite covering MIDI learn, controller modes, macro and LFO audio, chance and ratchets, host PPQ seeks, dense automation at 44.1 / 48 / 96 kHz and DPI behaviour. Both gate the package.
Per-file checksums
The release ZIP carries a manifest of every file with its own SHA-256, so what you downloaded can be checked against what was built.
One logo, two renderers
The mark is generated by a script and drawn as vectors in the editor from the same geometry, and a test compares the two renders pixel for pixel so they cannot drift.
Found something wrong? Open an issue on the repository — and if it is the host misbehaving rather than the plugin, say which DAW and version, because the two look the same from the outside.
Looking for a full Goa trance synthesizer rather than a bass line? GoaSynth covers supersaws, trancegate, arp, OTT and an AI patch designer.