Airchain — FM Radio Airchain Emulation | VST3 & AU Plugin for macOS

01 / The chain

Ever wondered why everything sounds better on the radio?

It isn't an accident — it's a rack of processing gear between the studio and the antenna. Airchain models every stage of it, in order, and points the whole thing at your mix.

Stage 1

AGC

The patient studio engineer that rides your levels before the fireworks start.

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Stage 2

Phase Rotator

The classic broadcast trick that tames spiky vocals before they hit the limiters.

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Stage 3

Four-Band Squash

L / LM / HM / H compression, all driven at once by the SQUASH knob — with live gain-reduction meters.

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Stage 4

FM Emphasis

EU 50 µs / US 75 µs — the real reason radio highs shimmer like that.

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Stage 5

Soft Clipper

Oversampled. Loudness, density, attitude — ceiling respected.

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Stage 6

Transmission

Hiss, pilot tone, flutter and blend — from pristine signal to pirate station three hills away.

Turn up SQUASH. Feel your track lean forward. That's the airchain working — and a Mix knob lets you parallel-crush anything.

02 / Features

A transmitter rack's worth of processing. One big knob.

The SQUASH Knob

One macro drives the entire four-band section: thresholds sweep −20 to −45 dB, makeup rises to +6 dB, releases speed up at the top. The loudness war, on a dial.

0 – 100 % · drives all four bands

Four-Band Compression

Low, low-mid, high-mid and high bands squashed in parallel, with live gain-reduction meters so you can watch the loudness war happen.

L / LM / HM / H

FM Emphasis

Genuine 50 µs (EU) and 75 µs (US) pre-emphasis curves — the boost real transmitters apply, and the reason radio highs shimmer.

EU 50 µs · US 75 µs · exact null in tests

Oversampled Soft Clipper

Loudness, density, attitude — with oversampling keeping aliasing down and the ceiling respected. Six samples of latency, correctly reported.

Up to +12 dB drive · 15k lowpass

Transmission Artifacts

Hiss, 19 kHz pilot tone, flutter and multipath blend — dial in anything from a pristine signal to a pirate station three hills away.

Hiss · Pilot · Flutter · Blend

Built-in Help Mode

Press ? and any control under your cursor gets spotlit and explained in plain English, with the actual numbers underneath. No manual required.

Every control · plain English

03 / Presets

14 presets, three flavors of radio.

Every preset is loudness-matched, so switching compares character, not volume. Your ears stay honest.

Eras

A time machine — from warm 1970s gold through the full-tilt 1990s CHR loudness war to today's streaming-safe conservative sound.

1970s Gold1990s CHR Loudness WarModern Conservative

Characters

Instant atmosphere for lo-fi, synthwave, vaporwave and film cues — distance, hiss and flutter on tap.

Late-Night DriveHighway FadeDistant SignalPirate Transmitter

Utility

The serious tools hiding inside the fun ones — for mastering checks and bus processing.

Mastering PreviewParallel CrushClean Airchain

Use it for

Mastering previews — hear how your track survives real-world broadcast processing.
Lo-fi, synthwave, vaporwave — instant era-correct radio character.
Film & game audio — diegetic radio sound with distance, hiss and flutter on tap.
Drum bus destruction — Parallel Crush at 35 % mix is a legal high.
Making literally anything sound 20 % more exciting — radio engineers have known this for 50 years.

04 / Pricing

One price. Every format. Yours to keep.

Full License

€19one-time

No subscription. No dongle. Buy once, use it everywhere.

VST3, AU & standalone app — macOS Universal
Full six-stage airchain, one SQUASH macro
14 loudness-matched presets
Built-in help mode — no manual required
Free updates

Buy on Gumroad — €19

Specs

Tested 44.1 – 192 kHz, mono and stereo. 6 samples latency, correctly reported. Passes Apple's auval plus an automated DSP test suite — flat crossover, exact emphasis null, bit-exact silence.

VST3AUStandalonemacOS Universal

Questions, answered.

What formats and systems does Airchain support?

Airchain ships as VST3, AU (Audio Unit) and a standalone app for macOS — a Universal binary that runs natively on Apple Silicon and Intel. It passes Apple's auval validation. A Windows build is not available at launch.

What does the SQUASH knob actually do?

It drives the whole four-band section at once, the way a station engineer would push the processing harder: thresholds sweep down from −20 dB to −45 dB, makeup gain rises to +6 dB, and releases speed up at the top of the range for that pumping CHR density. One knob, the entire loudness war.

Does it add latency?

Six samples, from the oversampled soft clipper — correctly reported to your DAW so plugin delay compensation keeps everything aligned. At 44.1 kHz that is about 0.14 ms.

Do the presets change loudness when I switch?

No — every one of the 14 presets is loudness-matched, so flipping between a 1970s gold chain and a full-tilt 1990s CHR chain compares character, not volume. Your ears stay honest.

Do I need to know broadcast engineering to use it?

Not at all. Press ? and help mode spotlights any control under your cursor and explains it in plain English, with the actual numbers underneath. And when in doubt: turn the big knob.

How do I buy it, and are updates free?

Airchain is sold through Gumroad as a one-time €19 purchase — no subscription, no dongle. You get instant access to the installers, and future updates are free for license holders.

Turn the big knob.

The entire FM airchain, pointed at your mix — for €19.

Get Airchain · €19 Follow @mrthymusic

Show Clock

Your mix, but ON THE RADIO.

Ever wondered why everything sounds better on the radio?

A transmitter rack's worth of processing. One big knob.

The SQUASH Knob

Four-Band Compression

FM Emphasis

Oversampled Soft Clipper

Transmission Artifacts

Built-in Help Mode

14 presets, three flavors of radio.

Eras

Characters

Utility

One price. Every format. Yours to keep.

Questions, answered.

Turn the big knob.

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