ACQUA - Ruby2


D.W Fearn's VT-5 vacuum-tube equalizer

RUBY 2 is a VST/AAX/AU plug-in that faithfully replicates the operational mode and classy sonic imprint of the highly prized VT-5 vacuum-tube equalizer built by D.W. Fearn. The VT-5 has been lovingly conceived, perfected, designed, and finally produced by D.W. Fearn due to his long-standing experience as a recording engineer/audio designer who is used to working with the best existing audio processors.
Over the years, D.W. Fearn has come to know the sound he’s after, like the back of his hand: because of this, the task of producing a convincing digital replica of his processors has proven to be an impossible mission for a long time.

Several past attempts have been discarded by the man himself, just because he felt something was lacking in the various proposed digital emulations, so much that he didn’t feel confident enough as to put his brand name (and his credibility) on those half-baked efforts.

It took Acustica Audio’s proprietary sampling technology to finally succeed in the difficult task of appeasing D.W. Fearn; only RUBY 2 could convince him to release a digital replica of his stellar equalizer in a plug-in format with his name on it.



Ruby is an official endorsement and a faithful representation of the D.W. Fearn highly sought-after vacuum tube equalizer VT-5. The original hardware equalizer uses passive LC circuitry with class-A triode vacuum tube stages for the input and output. The input transformer is made by Jensen. The output stage utilizes the same custom Jensen transformer used on the VT-1/VT-2 mic preamps.

The preamp stage dynamically recreates the pass-through sonic coloration of the original unit. This includes the harmonic distortion behavior of the hardware, the inherent phase shift, and frequency response deviations.

When the preamp is switched off, the plug-in offers a much cleaner and more linear sonic character than the hardware. Gain staging into the plug-in behaves similarly to hitting the original unit at different input levels, so Ruby comes with an "Input Trim" control. This allows for one-knob internal gain control by means of hidden linked input and output gain stages.

For details about the installation/authorization process, please refer to this page.

Technical Specs

  • Core 16
  • Available sample rates: 44.1kHz | 48kHz | 88.2 kHz | 96kHz

All updates and bug fixes will be available inside Aquarius under the 'Updates' section.
All other trademarks and trade names mentioned on this page are used for identification purposes only and are properties of their respective owners.



Operating System Windows7 Windows10 OS X 10.8 OS X 10.13
CPU Quad Core Latest multicore CPU (1) Quad Core Latest multicore CPU (1)
RAM 4 Gb 16 GB to 128 GB 4 GB 16 GB to 128 GB
HDD/SDD 4000 Mb 4000 Mb 4000 Mb 4000 Mb
Screen Resolution 1024x768 (XGA) 1920×1080 (HDTV) 1024x768 (XGA) 1920×1080 (HDTV)
Audio Host VST2/AAX 32 bits VST2/AAX 64 bits VST2/AU/AAX 32 bits VST2/AU/AAX 64 bits

(1) Intel i7 or Intel i9 generation 4 or 8 or newer is recommended.

Acustica reserves the right to change these specifications without notice in any time.



ACQUA - Ruby2

  • LIST PRICE: €235.00