Empirical Labs Arousor Review featured image

Empirical Labs Arousor Review

If you enjoy this review and decide to grab the deal, please consider clicking through one of my links before you buy. I earn a small commission at no cost to you, which helps support this site and keep the reviews coming. Thanks!

Most compressor plugins based on hardware tend to emulate the same small handful of vintage hardware compressors: the LA-2A, the 1176, and the SSL bus comp. A much less commonly imitated model is the Empirical Labs Distressor, a more modern VCA hardware unit that has been a mainstay of recording studios since the late 90s. Empirical Labs just announced the v3 release of the Arousor, which is the plugin version of their Distressor hardware unit. I was excited to get my hands on their official in-the-box equivalent to their rackmount compressor and run it through its paces. Check out the video review below, then scroll down for even more details about the new Arousor:


Empirical Labs Arousor Review main plugin image

The Arousor is a close visual match to the Distressor with a few key differences. The original hardware unit has a flat black paint job with white pinstriping, while the Arousor has a charcoal grey matte brushed metal look with blue lines. The same big white knobs and fonts adorn the controls, but all of the extra features employ smaller black knobs. The default values are marked in blue on the dials for reference. There are lots of subtle jokes in the controls, and the interface is easy to understand and work with.

Looks 5 Stars


Let’s dive into the numerous features in the Arousor:

(Note: If you’re not terribly familiar with basic compressor operation, check out my article How to Use a Compressor Plugin for more info.)

Input, Output, Attack, and Release

Empirical Labs Arousor Review input output attack release

Along the top of Arousor are the four main big white knobs, just like on its big brother, which control input and output gain, plus attack and release. There’s no threshold control, similar to a leveling amplifier, so the thresholds are baked into the ratio controls. The gain reduction meter runs along the tippy top, including the BAD! Clip light, which is a hilarious addition. What isn’t in the original hardware unit are the A and B Opto buttons, which modify the attack and release curves to mirror the curves on a vintage or modern LA-2A. When engaged, the Opto also displays orange text below many of the knobs, which when clicked sets them to the values to best emulate the hardware. There are also presets that load all of those settings at once.

Ratio, Attack Modification, and Soft Clipping

Empirical Labs Arousor Review ratio attack mod soft clipping

The original Distressor unit has eight different compression ratios. Version 3 of Arousor comes with twelve, including two new ones that are part of the added functions with the Opto models: 6.5:! and 7:1. Clicking the Alt button brings up the two new ratios. RIVET is the name they gave to the infinity mode, which is the same idea as the NUKE setting on the Distressor with a different name.

The Attack Modification function allows you to set your own soft knee on the attack. Already a soft-kneed compressor, this control makes the knee even softer, and includes lights to let you see just how soft. The soft clipping adds saturation and harmonics, and has a meter with fun titles like “Pinned” and “Toasty.” Clicking the “e” button brings up the Expert Menu, which gives you direct control over the amount of 2nd harmonic distortion as well as the ability to stick the soft clipping in the signal path before or after the compression.

Detector EQ and Blend

Empirical Labs Arousor Review detector EQ blend

The detector EQ controls are very robust in Arousor, including a high pass which is fantastic for dialing in the perfect compression on sources with lots of low-frequency energy, and a sidechain EQ which allows you to find trouble frequencies in a signal and push more of them into the detector to enable more squash in that range. The blend control sets the overall dry/wet mix, and hitting the expert menu brings up a dry signal control which varies the amount of dry signal that bypasses the detector circuit.

Features 5 Stars


Simply put, this compressor rocks. I threw it at basses, drums, guitars, vocals, and whole busses and couldn’t find a source it wasn’t well-suited for. The ratio controls with the built-in thresholds are fantastic, and having twelve different ones makes Arousor incredibly versatile, even without all of the other features. The soft clipper is probably my favorite feature, and when added to a master alleviates the need for exciters or separate saturation plugins. Also, Arousor is incredibly light on CPU use, which means you can do fun stuff like throwing two or three compressors together on a buss to knock off big transients then even out a performance. Adding the Opto mode also makes this plugin a competitor for all of the LA-2A clones in your plugin folder. I could go on and on, but to say it’s an extremely usable plugin is an understatement.

A few months back I was going to review the Big FrEQ equalizer plugin, also from Empirical Labs, but decided not to because I didn’t want to buy a hardware dongle just to do a review. Luckily Empirical Labs has decided to get on the iLok Cloud bandwagon, so now you can enjoy Arousor without the hassle of hardware, which is great news and a boon to its usability as well.

Usability 5 Stars

Hear it in Action

Here’s a dry drum track to start with no effects other than a light plate reverb:

Here’s the same drum track with the Arousor giving it just the right amount of slam:

Now here’s Arousor taking some stray transients out of a master buss:

Here’s the exact same clip without the Arousor on the master. The difference is subtle since it’s in the mastering chain, but listen for the louder transients:

Empirical Labs Arousor Review – The Bottom Line

Value was the thing I was most concerned with before I loaded up the Arousor. Afterwards, however, I have zero concerns. Considering the hundreds or even thousands of dollars of compressor and saturation plugins that this replaces all in one, it’s well worth the price. I’m not saying that I will never use another compressor plugin, but I definitely will load up Arousor before any other to see how it sounds before moving down the list. In short, it’s worth every penny and more.

Value 5 Stars

I can’t say enough about the Arousor. It’s an absolute knockout of a compressor plugin.  Numerous ratios, multiple attack and release curves with attack modification, soft clipper, detector EQ, and tons of good presets make this a solid 5 stars in every category and my new favorite compressor plugin. If you’re using compression in the box, which is almost everyone, I dare you to try it out and not fall in love. If you see it on sale, don’t think twice.

Overall Rating 5 Stars

Disclaimer Text!
Empirical Labs Arousor Review main plugin image

The Arousor is the plugin version of Empirical Labs' legendary VCA soft-knee compressor called the Distressor, which adds more features and options to the original for less than a sixth of the price.

Scroll to Top