PAA Audio – American FET v1.1.1 for WiN

American FET | FET 500 series compressor, thanks to which American records sounded in a new way.

Each unit was measured at the factory before shipping. Fixed readings, pass or fail. American FET is calibrated to the same list and matches all six levels in Compress and Limit modes.

Listen before you buy. Next up: the same plug-in option, with levels matched so no one sounds louder than the others. Switch between them and choose.

One knob does all the work. CEILING compresses the signal and returns it to the original level, so you can rely on it and eventually get back where you started.

Color with the compressor off. In OFF mode, the discrete amp and transformer remain in the signal path, so you get cantilevered weight on tracks that don’t need compression.

The circuit works as long as there is an audio signal passing through it. Insulated-gate FET, discrete op-amps as transistor stages, custom-hardware transformer.

It’s fast. A JFET controls the gain, so the capture occurs before the transient is complete, and the discrete op amps behind it change color while it’s engaged. Attach it to a room mic, and distance becomes weight; in a trap, it finds the right touch. On vocals, it holds the line without even sounding like it’s holding anything.

There’s a reason this design is still used in racks that already have three other compressors installed. It lacks subtlety. The drums sound like a recording, not a session, and they’re audible across the room, not after the third track.

• Ceiling stages are separated from the resistive ladder in the schematic. 2 dB per stage, measured by components, not by the curve
• The DS sidechain filter is separated from the switching network in the schematic, including the part that no one notices: it boosts both low and high frequencies.
• The output transformer is the same as in the original, modeled using our own hardware. When used, it saturates, not simply increases volume.
• The detector restores its peak between samples at around 380 kHz, regardless of the operating speed of your device, so short transients are captured where a conventional digital detector indicates a low level.

All of this is recorded, including places where the model still differs from the measured equipment.

Uncompressed Color

Switch the mode to OFF, and the gain cell will move away, but the discrete output amplifier and transformer will remain in place. Now OUT is not a volume control, but a tone control: press it, then pull TRIM towards you to set the desired level.

When working with a quiet source, this path remains clear. Feed it a “hot” track and press OUT, and the compressor will begin working, with the third harmonic significantly ahead of the second, as if a push-pull output stage were saturating. This is a cantilevered weight on a track that doesn’t need compression at all. Most compressors force you to choose between the two options. This one doesn’t.

What you get?

• Four modes: C is 2:1 compression that doesn’t interfere, L is 20:1 limiting that completely stops the signal, OFF is amp and transformer without dynamics, BYP is a true bypass.
• CEILING is the only control you need for compression. One press and you go from gentle compression of a couple of dB to full limiting.
• Four release times on the front panel: from 0.1 sec to 2.5 sec.
• DS tilts the detector towards the high end. When working with vocals, it turns into a de-esser without a separate plugin.
• External sidechain, Dual / Stereo-link / Mono modes, dry and wet mix for parallel operation, and a post-transformer TRIM function so you can use the amp without going over your level.
• Peak display below the meter so you can see exactly what was removed.

What’s different about PCCN?

Traditional DSP models model the result: a fixed saturation curve, an impulse response, a neural fixation of behavior over the course of a single day. 

PCCN models the cause: the circuit adjusts as the audio signal passes through it. You hear what the curve can’t reach. The knee exits the rectifier in the detector, the slope increases as the gain cell runs out of space, and when a signal is applied to the output, the transformer responds before the amplifier.