Physical Audio's Tetrad Synth Plugin: Revolutionizing Sound Design

In a significant advancement for digital music production, UK-based software developer Physical Audio has unveiled its latest synthesizer plugin, Tetrad, which marries physical modeling techniques with innovative sound design inspired by real-world sculptures. Launched on July 28, 2025, Tetrad is now available in VST3, AU, and AAX formats, marking the company’s fourth such product aimed at modern electronic musicians.

Tetrad's design is notably influenced by the experimental art of musician and artist Gadi Sassoon, whose original installation, the "Sculpture-based Synth," utilized slashed metal plates with a custom Max/MSP setup to forge unique soundscapes through tangible interaction. Tetrad serves as a digital counterpart to this installation, translating its tactile essence into a versatile plugin format that forges new pathways in audio synthesis.

At the heart of Tetrad lies a sophisticated four-voice engine that offers an expansive range of signal manipulation. Each oscillator can operate in several modes, including Basic, Chords, Modal Chords, Free, and Flex, and is equipped with FM synthesis controls. Notably, Tetrad features three distinctive processing modules: Quad AM, Quad Granulator, and Quad Plate Resonators, which enhance user control over sound at both global and individual voice levels.

As described by Dr. Sarah Johnson, a Professor of Music Technology at Berklee College of Music, "Tetrad’s integration of physical modeling and MPE (MIDI Polyphonic Expression) is a game changer, allowing musicians to explore sound in ways that were previously unattainable with traditional synthesizers." The Quad AM module, for instance, introduces phase-based modulation with adjustable parameters for shape, depth, gain, and rate, while the Granulator module enables granular synthesis with features like grain size, feedback, and pitch variation.

The Plate Resonators within Tetrad simulate the acoustic properties of slashed metal plates, allowing users to graphically manipulate their positioning on a virtual stage. This feature enables sound designers to adjust the decay, drive, and tonal shaping of the simulated plates, further enhancing the plugin’s experimental capabilities. Additionally, Tetrad supports a glide range of ±48 semitones and includes a sidechain input and quad-channel output, making it adaptable for diverse musical applications.

Physical Audio's commitment to real-time computation and avoidance of sample-based synthesis positions Tetrad as a forward-thinking tool for musicians seeking nuanced control. According to industry analyst Mark Thompson, CEO of SynthTech Solutions, "As DAWs evolve, tools like Tetrad will become essential for artists who wish to push the boundaries of sound design and performance. The reliance on real-time modeling rather than pre-recorded samples fosters a more organic sound, thus bridging the gap between digital and physical music creation."

Tetrad arrives at a pivotal time when the demand for innovative sound tools is surging among electronic musicians. The trend towards high-resolution modulation and real-time interaction is reshaping the landscape of music production, making Tetrad a timely addition to the arsenal of both amateur and professional sound designers.

The plugin is currently offered at an introductory price of $59, with a standard price of $99 set to take effect shortly after its launch. As the music production community embraces these new technologies, Tetrad's introduction could herald a new era in electronic sound design, emphasizing the convergence of art and technology in music.

Overall, Tetrad not only exemplifies Physical Audio's dedication to pioneering audio technology but also reflects a broader movement within the music industry towards embracing innovative methodologies that enhance creative expression and artistic exploration. As this plugin gains traction among musicians, its impact on the future of sound design remains to be seen, potentially influencing the development of subsequent audio tools and technologies.