Cardinal vs SynthMaster 3
Cardinal
cardinal.kx.studioSynthMaster 3
kv331audio.comSide by side
| Figure | Cardinal | SynthMaster 3 |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | Yes |
| Open source | Yes | — |
| Web | Yes | — |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | — |
| iOS | — | Yes |
| API | Yes | — |
| Self-hosted | Yes | — |
| Plans published | 2 | 9 |
| Spec score · Software Synthesizers | 9.0 (#2) | 8.6 (#5) |
| Documentation depth | The official site documents OSC activation, ports, message formats and headless configuration, while general usage relies heavily on VCV Rack documentation. | KV331’s downloads page exposes a SynthMaster 2.8 manual, while an independent 2026 report says written SynthMaster 3 documentation was absent and an unofficial manual was created. |
| Product | Cardinal is a free, open-source virtual modular synthesizer based on VCV Rack and packaged as a self-contained plugin and standalone app. | SynthMaster 3 is a modular software synthesizer available as a plug-in. |
| Support | The maker asks users to report bugs on GitHub and lists the #cardinal IRC room on Libera.Chat for community discussion. | The maker directs users with product support issues to its contact form. |
| What it does | Cardinal is a virtual modular synthesizer based on VCV Rack, delivered as plugins and a standalone application. | SynthMaster 3 is KV331 Audio’s flagship semi-modular software synthesizer for sound design and music production. |
Plans
SynthMaster 3
- SynthMaster 3$99, paid once
- SynthMaster 3 Free BetaFree
- SynthMaster 3 upgrade from SynthMaster 2$29, paid once
- Upgrade from SynthMaster 2$29, paid once
- SynthMaster 3 upgrade from SynthMaster 3 Player$49, paid once
- SynthMaster 3 upgrade from SynthMaster One$49, paid once
- Upgrade from SynthMaster 3 Player$49, paid once
- Upgrade from SynthMaster One$49, paid once
- Everything Bundle$249, paid once
In their own words
Cardinal
Cardinal is a free, open-source modular synthesizer based on VCV Rack, available as a standalone app and as a plugin. It bundles 1,382 modules from 84 authors or brands, but does not load external modules or connect to the official Rack library or store; modules cannot be added to an existing build. Cardinal runs on Linux, macOS, Windows, and the web. Its plugin formats are AudioUnit, CLAP, LV2, VST2, and VST3, with Main, Synth, and FX variants that all support MIDI input and output. Main provides eight audio inputs and outputs and ten CV inputs and outputs, but is unavailable in AU and VST2 and is not yet available in CLAP. Mini has a smaller hand-picked module selection, two audio ports, and five CV ports, and is available only as LV2 or standalone. OSC remote control works in standalone use, not in the plugin. The project describes Cardinal as stable, while noting CLAP support is still in progress and VST3 hosting inside Carla or Ildaeil is experimental. It is licensed under GPLv3+.
SynthMaster 3
SynthMaster 3 is a modular software synthesizer available as a standalone app and plug-in for macOS and Windows. It offers VAnalog, additive, vector, wavetable, granular, phase modulation, phase distortion, frequency modulation, pulse width modulation, ring modulation, physical modeling, and SFZ sample playback. Each instance can contain up to 16 layers, with each layer holding up to 16 modules and 32 modulation sources. The software includes waveform, wavetable, and multi-sample editors; multi-samples can be imported from WAV or AIFF files and exported in SFZ format. Each layer has a MIDI output channel for routing arpeggiator or sequencer output to different DAW tracks. Plug-in formats are VST2, VST3, AudioUnits, and AAX. The product includes 3150 factory presets. SynthMaster 3 costs $99, paid once and includes 6 free expansions. A free player and demo are also available. The demo stops after 30 minutes, adds noise every minute, and disables WAV wavetable and SFZ multi-sample export.