VLA-FET

About the VLA-FET

Inspired by the classic 1176 FET compressor: the leveling amplifier that defined "fast and loud". The VLA-FET is our take on the discrete FET design, built around a modelled FET compression amp, an output transformer with real flux saturation and a discrete Class-A stage — then given a couple of modern tricks the original never had.

The VLA-FET is a vintage FET compressor, and it plays a completely different game from an opto unit. Where an optical cell breathes, a FET clamps — fast, hard and with attitude. The attack sweeps down to roughly one millisecond, faster than almost anything of its era, which is exactly why the 1176 became the drum-and-vocal weapon it is. You drive the Input gain to set how much compression you get, use Output gain to make up level, and pick a Ratio from a gentle 4:1 up through 8:1, 12:1 and a firm 20:1 — or the notorious All mode. Simple to handle, intense in effect, and never fussy about it.

The 1176: the FET that changed tracking

The original arrived in the late 1960s as one of the first true FET compressors, using a field-effect transistor as the variable-resistance element instead of a tube or an optical cell. That let it react far faster than anything before it, and its aggressive, forward sound turned it into a studio fixture within a few years. We modelled the VLA-FET as a living circuit: the FET compression amplifier, the output transformer with its genuine flux saturation and the discrete Class-A output stage, all simulated in real time with our SPICE-style approach. It moves fast, colours hard, and keeps that unmistakable FET grit — with adaptive oversampling running up to 4x under the hood to keep the fast transients clean.

Sound, ratios and the famous All-buttons mode

The VLA-FET hits with the punch and grit the 1176 is loved for. The Ratio switch steps through 1:1, 4:1, 8:1, 12:1 and 20:1, then lands on All — the legendary "all-buttons-in" mode where every ratio is engaged at once for that gnarly, aggressive, distorted crush famous on room mics and parallel drums. Attack is very fast (roughly 1 to 7 ms), Release is fully sweepable, and an Auto Fast mode adapts the release to the program for hands-off control on dynamic material. Set the Meter to watch Input, Gain Reduction or Output, and push the Input gain hard so the output transformer and Class-A stage add saturation you can lean on as an effect.

Using the VLA-FET on drums, bass and vocals

Drums are the VLA-FET's home turf: fast attack, high ratio and it turns a limp snare into a crack, or slam a whole kit into All mode on a parallel bus for that exploding-room sound. On bass it locks the low end in place with punch and consistency the source rarely has on its own. On vocals it adds urgency and forward presence — pick a moderate ratio and let the fast attack tuck the peaks. Three modern additions go beyond the hardware: the Sidechain Highpass (7.5 Hz to 1 kHz) stops heavy low end from over-triggering the compression, a real External Sidechain input lets you duck from another source, and the Mix knob blends dry and processed signal from 0 to 100% for instant parallel compression. Link stereo-links the detector for coherent bus work. Want smooth, slow optical leveling instead? Reach for the tube-based VLA-2A or the brighter opto-hybrid VLA-3A.

VLA-FET Features

True FET compression with very fast attack

A modelled FET compression amplifier gives the VLA-FET its razor-fast attack (roughly 1 to 7 ms) and the punchy, aggressive character that made the 1176 a tracking legend. Input gain drives the amount of compression while Output gain sets make-up level.

Ratio 4:1 to 20:1 plus All mode

The Ratio switch steps through 1:1, 4:1, 8:1, 12:1 and 20:1, then engages All — the famous "all-buttons-in" mode that slams the signal with gnarly, distorted, aggressive compression, perfect on parallel drums and room mics.

Release control with Auto Fast

The Release knob sets recovery time, while Auto Fast switches to a program-dependent release that adapts to the incoming signal — keeping busy, dynamic material controlled without constant knob-riding.

Sidechain Highpass and External Sidechain

A sidechain high-pass filter sweeps from 7.5 Hz up to 1 kHz so heavy low-end energy stops over-triggering the compressor, keeping kick and bass full. A real External Sidechain input lets you trigger compression from another source for ducking and rhythmic effects.

Wet/Dry Mix and stereo Link

The Mix knob blends processed and dry signal from 0 to 100% for instant parallel compression, while Link stereo-links the detector so both channels react together for a stable, coherent stereo image. The Meter switches between Input, Gain Reduction and Output.

Output transformer and discrete Class-A stage

An output transformer modelled with genuine flux saturation and a discrete Class-A output stage give the VLA-FET its analog weight and colour. Push the Input gain and both add harmonic saturation you can use as a deliberate effect.

Authentic circuit emulation

Our real-time, SPICE-type component-based circuit simulation captures the sound and feel of the analog counterpart in every nuance — the FET compression amp, output transformer and Class-A stage all faithfully modelled.

SSE2-optimised code

DSP operations are pipelined on the SSE2 instruction set for high-performance operation, even under complex processing.

Adaptive oversampling up to 4x

Adaptive oversampling runs up to 4x and auto-adjusts to your session's sample rate, attenuating aliasing on the fast FET transients while saving CPU when it can stay transparent.

HighDPI / Retina support

Crisp, high-pixel-density rendering on macOS and Windows for a sharp interface on modern displays.

VLA-FET Examples & Videos