Start your trial

Bus compressor · included in the subscription

The A-Paralel Bus: the glue on your mix bus

The compressor that goes at the end of the bus and makes the tracks stop sounding separate and start sounding like a record. With parallel mix built into the plug-in. It joins the Astra Sampler FX subscription — if you are already in, it is yours at no extra cost.

Join the subscription

Astra A-Paralel Bus compressor panel

What it does

It is a classic bus compressor: threshold, attack, release, ratio and make-up, with the usual switched values instead of continuous knobs — because on a bus there are about four positions that work and the rest are in the way.

What gives it its name is the MIX knob: parallel compression is built in, so you do not need a send or a duplicated bus. Squeeze as hard as you like, then decide how much of that you hear.

The AUTO release runs in two stages — a fast 100 ms and a slow 12 s — which is what stops the bus pumping when a loud snare comes in.

What you get

It is included in the subscription. Not a separate purchase: if you have Astra Sampler FX you have this, and the subscription price does not go up for it.

From 28 September it will also be sold on its own, for anyone who only wants the compressor.

Why try it

Because we publish what we measure. These figures come from our own bench, on the same build you download, with the hardware it models right next to them.

0.000 dBHonest threshold

Raising the input 3 dB does exactly the same as lowering the threshold 3 dB. Zero drift.

0.17 msFastest attack

With 0.1 ms asked for. At the 30 ms position it measures 32.9: the markings tell the truth.

−160 dBFSDC at the output

No offset. You can chain it without anything piling up.

7.0 sAUTO tail

The slow stage takes this long to let go of 90 %. That is why it does not pump.

And where we don't win

The three ratio positions land a touch under the hardware: measured slope 0.49 / 0.72 / 0.88 where the original gives 0.50 / 0.75 / 0.90. In plain terms: it squeezes slightly less than the knob says, mostly at 4:1 and 10:1. It is small — tenths — but it is measured, and we are not rounding it in our favour.

We say it because the whole bench travels with the press kit: anyone can repeat these measurements and find the same.

Formats and requirements

macOS: VST3, Audio Unit and standalone app, universal binary (Intel and Apple Silicon), macOS 10.13 or later. Windows: 64-bit VST3, Windows 10 or later. Mono and stereo, any sample rate.

One heads-up: the installers are not signed with a paid certificate, so macOS will say it cannot verify the developer and Windows may warn via SmartScreen. On macOS you approve it in System Settings > Privacy & Security.