The Rupert Neve Designs OptoFET is a highly versatile analogue compressor and wave shaper that combines a newly developed FET compression circuit with an optimised optical compressor in a single 1U rackmount unit. Designed to move effortlessly from transparent dynamic control to extreme envelope shaping with rich harmonic content, the Rupert Neve Designs OptoFET is intended for tracking, mixing, and creative sound design applications where flexibility and tonal character are equally important.
At the heart of the Rupert Neve Designs OptoFET are two independent compression engines that can operate either together or separately, depending on the selected global mode. In Dual-Stage mode, the FET and OPTO compressors are placed in series, allowing precise, multi-stage control over complex sources. This configuration mirrors a common high-end recording and mixing technique, enabling fast transient control followed by smoother, programme-dependent levelling within a single unit. The order of the compressors can be freely switched, allowing either FET into OPTO or OPTO into FET operation.
In Dual-Band mode, the Rupert Neve Designs OptoFET becomes a true two-band analogue compressor. A variable crossover allows the signal to be split between low and high frequency bands, with each compressor assigned to one band and operating independently. The crossover frequency is continuously adjustable from 50Hz to 500Hz, and the compressor assignment can be flipped, enabling the FET or OPTO section to process either frequency range as required. This provides powerful control over low-end energy, midrange punch, and high-frequency texture, particularly useful for bass instruments, drums, and full mixes.
The FET compressor section of the Rupert Neve Designs OptoFET is an all-new design developed specifically for this processor. It delivers ultra-fast attack times down to 100 microseconds, along with variable attack, release, threshold, and up to +20dB of make-up gain. Ratio options of 4:1 or 8:1 are provided, along with a 125Hz sidechain high-pass filter to prevent low-frequency content from triggering excessive gain reduction. A continuously variable Blend control allows precise parallel compression directly within the unit.
A unique GRIT mode transforms the FET compressor into a harmonic wave shaper, introducing pronounced upper-frequency harmonic distortion. GRIT can be used subtly to add presence and edge, or pushed harder for more aggressive tonal transformation. When combined with the Blend control, it allows extremely precise control over the amount of distortion introduced.
The OPTO compressor section is designed to complement the speed and brightness of the FET stage with slower, smoother dynamics and enhanced low-frequency harmonic content. Variable attack, starting at 5 milliseconds, release, threshold, and up to +20dB of make-up gain are provided, along with Blend control and selectable ratios of 2:1 or 5:1. A 125Hz sidechain high-pass filter is also included. The OPTO section introduces its own unique BLOOM mode, which significantly increases low-order harmonics, adding warmth, weight, and low-end presence. BLOOM can often replace traditional equalisation for final tonal shaping, particularly when used in parallel.
Both GRIT and BLOOM differ fundamentally from Rupert Neve Designs SILK processing. Rather than relying on transformer saturation, these modes are generated through the interaction of the compressor circuits with newly developed sidechain designs. This allows far more dramatic wave-shaping effects, with harmonics extending well beyond traditional saturation characteristics.
Gain staging flexibility is central to the Rupert Neve Designs OptoFET design. Global input and output trim controls of ±12dB allow precise control over levels, ensuring transparent compression or deliberate driving of the compressors for enhanced harmonic character. Each compressor also features its own make-up gain, which can be used creatively in both Dual-Stage and Dual-Band modes to shape tone, balance frequency bands, and explore gain-dependent behaviours.
Features
- Newly designed FET compressor and optimised optical compressor in a single 1U unit
- Dual-Stage mode for serial FET and OPTO compression with switchable order
- Dual-Band mode with variable crossover for independent low and high frequency processing
- Continuously variable crossover frequency from 50Hz to 500Hz
- Ultra-fast FET attack times down to 100 microseconds
- GRIT mode for upper-frequency focused harmonic wave shaping
- BLOOM mode for enhanced low-order harmonics and low-end warmth
- Independent Blend controls for parallel compression on each compressor
- Selectable compression ratios on both FET and OPTO stages
- 125Hz sidechain high-pass filters on both compressors
- Global input and output trim for flexible gain staging
- Up to +20dB of make-up gain per compressor stage
- Transformer-balanced output stage
- Expandable to dual-mono operation using two units