The OptoFET is a highly versatile analog compressor and wave‑shaper designed to deliver everything from transparent vocal control to extreme tonal shaping with rich harmonic texture. It merges a brand‑new Rupert Neve FET compression circuit with an optimized optical compressor in a compact 1U chassis, giving engineers a powerful and musical dynamics tool for tracking, mixing, and sound design.

Dual Compression Architectures for Maximum Control

The OptoFET provides two distinct operating modes:

Dual‑Stage Mode
The FET and Optical compressors are run in series—replicating a classic studio technique for achieving complete dynamic control. This setup offers both the fast punch of FET compression and the smooth leveling of optical compression in a single pass.

Dual‑Band Mode
The two compressor circuits are split into low and high frequency bands, allowing independent processing of each range. This opens up new creative opportunities for tone sculpting, transient control, and mix‑bus shaping.

All‑New FET Compressor Design

The FET section features lightning‑fast attack times down to 100 microseconds, with finely tuned response and familiar ratio options. It includes variable Attack, Release, Threshold, Makeup Gain, and a wet/dry Blend control for parallel compression. A switchable 125 Hz sidechain high‑pass filter prevents low‑frequency energy from triggering unwanted gain reduction.

A standout feature is GRIT, a harmonic enhancement mode that transforms the FET circuit into a wave‑shaper—adding upper‑frequency harmonic energy for presence, edge, and creative saturation.

Optimized Optical Compressor

The optical compressor is designed to complement the FET circuit with smooth, musical behavior. Similar variable controls ensure precise shaping, while maintaining the warm, natural envelope characteristic of optical compression. Its response makes it ideal for vocals, bass, guitars, and bus leveling.

High‑End Workflow & Construction

Every variable parameter is controlled via 31‑position detented potentiometers, allowing precise recall and stereo matching when using two units. The layout is intuitive and designed for fast, confident operation in professional environments.

Key Features

• Dual compression engines: newly designed FET section + optimized Optical section
• Two operating modes: Dual‑Stage (series) and Dual‑Band (frequency‑split)
• GRIT harmonic distortion mode for the FET compressor
• Independent controls for Attack, Release, Threshold, Makeup Gain, and Blend for each compressor
• 125 Hz sidechain high‑pass filter on the FET section
• Variable crossover control (in Dual‑Band mode)
• 31‑detent precision controls for repeatable settings
• Can be paired with a second unit for stereo operation
• Designed for tracking, mixing, mastering, and creative sound design

Technical Specifications

• FET Attack: 100 µs to 50 ms
• FET Release: 50 ms to 1.5 s
• Optical Attack/Release: Program‑dependent, musical response
• Ratios:
  • FET: 4:1 and 8:1
  • Optical: gentler, musical ratios
• Controls: 31‑detent pots for all variable parameters
• Inputs/Outputs: XLR + 1/4" combo input, XLR output
• Form Factor: 1U rackmount
• Use Cases: Vocals, bass, guitars, mix‑bus, stems, mastering, experimental shaping