Ruby 3
Ruby 3 is a high-end tube equalizer designed to recreate the authentic signature sound of the D.W. Fearn VT-5 through a new generation of hybrid modeling. Powered by Acustica Audio's NOVA architecture, it is built from the original unit provided by Doug Fearn and captures the full interaction between passive EQ sections and tube amplification, delivering enhanced harmonic accuracy, smoother tonal shaping, and a more natural response across all signal levels. Ruby 3 is available in VST3, AAX, and AU formats and is compatible with all major DAWs on macOS and Windows systems.
Doug Fearn’s Hand-Built VT-5

Ruby 3 is built from the personal VT-5 used by Doug Fearn himself - one of the earliest units ever made and his own reference for the sound of this legendary equalizer. This is not a generic production unit, but the original source behind Ruby.

This particular VT-5 carries a unique sonic identity. Built with high-grade components characteristic of early designs, it stays true to the VT-5 philosophy while expressing a distinct and recognizable voice.

Ruby 3 is designed to preserve exactly that voice - the authentic sound of Doug’s own reference unit.

Key Features
Original Unit

Based on Doug Fearn’s own hand-built VT-5 reference unit.

Deep Resampling

Advanced capture for greater detail and smoother response.

NOVA Preamp

Hybrid processing for accurate tone and nonlinear behavior.

Flexible Use

Ideal for tracks, buses, and mastering applications.

Extended Control

Auto Gain, Listening Modes (Left-Right, Delta, Mid, Side),

real-time EQ display.
Factory Presets

Ready-to-use presets for fast mixing and mastering.

Powered by NOVA

At the core of Ruby 3 is NOVA (Neural Optimized Volterra Audio), Acustica Audio’s hybrid architecture designed to accurately reproduce analog hardware behavior across the full dynamic range.

The result is a seamless transition between clean and driven behavior, preserving coherence, musicality, and realism at every level.

Technical information:
  • Supported formats: VST3, AAX, and AU.
  • Available sample rates: 44.1, 48, 88.2, and 96 kHz.
  • Compatible with Windows 10 and 11.
  • Compatible with macOS 10.15 (Catalina) to macOS Sonoma (version 14.x).
  • Native Apple Silicon support (Rosetta not supported).
  • Ruby 3 is a FREE upgrade for current Ruby users!