Tetrad by Physical Audio synth plugin interface

Tetrad: Physical Modelling and Granular Synth Plugin by Physical Audio

Rated 4.9/5 on Plugin Boutique (8 ratings)

Tetrad is a hybrid software synth from Physical Audio that combines physical modelling and granular synthesis. It uses four oscillators, quad amplitude modulation, a granulator and four modelled plate resonators.

VST3AUAAXWindowsmacOS

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01Overview

Tetrad is a plugin instrument built around a quad bus signal chain. Four oscillators can be routed through a 4×4 matrix mixer, a Quad Amplitude Modulation stage and a Quad Granulator, then shaped by four physically modelled plates. The developer, Physical Audio, created it with composer and transmedia artist Gadi Sassoon, and it was inspired by his sculpture-based synth installation. The result is a sound design tool aimed at textural, experimental and immersive work.

Best for

Experimental sound design
Textural pad creation
Granular processing
Microtonal composition
MPE controller performance
Sculptural ambient layers

Developer: Physical Audio
Category: Synths
Store: Plugin Boutique

02Key features

What you get

Quad oscillator unit with frequency modulation and multiple tuning modes
Sidechain audio option that bypasses the oscillators
4×4 matrix mixer blending four inputs onto four busses
Quad amplitude modulation with depth, shape, rate and phase per bus
Quad granulator with control over grain window, size, pitch and feedback
Four physically modelled plates with preamp drive and sound stage design
Three filter sections with lowpass, band or highpass modes
Modulation matrix with eight LFOs and MPE dimensions
Full MPE support with velocity, slide, pressure and glide sources
MTS-ESP micro tuning support

03In depth

Sound Design Architecture and Character

Tetrad's sound begins with four oscillators that can be frequency modulated and tuned in several ways, from basic intervals to diatonic inversions. A sidechain audio option bypasses the oscillators so any incoming signal can be processed instead.

The four busses then pass through Quad Amplitude Modulation, where depth, shape, rate and phase are set per bus. The granulator splits the signal into grains that can be reshaped by window shape, size, pitch and feedback. The four plate resonators add preamp drive and sound stage design, giving the sound a physical, resonant body.

Modulation, MPE and Tuning

A modulation matrix offers eight LFOs, MIDI values and MPE dimensions. The envelopes include the main ADSR as well as envelope-following signals derived from the AM and granulator levels.

MPE support makes velocity, slide, pressure and glide available as modulation sources, and pitchbend and glide remain continuous across the full MIDI note range in MPE mode. MTS-ESP micro tuning support is included for alternative tunings.

04Specs

Will it run?

Formats, systems and requirements as listed by Plugin Boutique. Missing details are left out, not guessed.

Developer	Physical Audio
Type	Plugin
Category	Synth
Formats	VST3, AU, AAX
Operating systems	Windows, macOS

05FAQ

Questions, answered

What formats does Tetrad support?

Tetrad is available in VST3, AU and AAX formats.

What operating systems does Tetrad run on?

Tetrad runs on macOS and Windows. The developer lists macOS Sierra 10.13 or above for AU, VST3 and AAX, and Windows 11 for VST3 and AAX, on Intel or Apple Silicon Macs and Intel or AMD processors.

Does Tetrad support MPE controllers?

Yes. Velocity, slide, pressure and glide can be used as modulation sources, and in MPE mode pitchbend and glide are available continuously across the full range of MIDI notes.