UAD Empirical Labs FATSO: Authentic Tape Warmth

Few analog units have left their mark on as many modern mixes as the Empirical Labs FATSO. Built to capture the musical characteristics of multiple compressors, Class A electronics, and the highly sought-after behavior of magnetic tape all in one box, it’s a favorite of legendary engineers with credits ranging from Willie Nelson to AC/DC.

Now, Universal Audio has brought that exact character into the digital realm with the UAD Empirical Labs FATSO Tape Simulator, fully endorsed by Empirical Labs founder Dave Derr.

Two Plugins in One: Jr and Sr

Universal Audio has essentially delivered two distinct plugins in a single package, giving producers the very sound that thickened the records of Soundgarden, Pearl Jam, and countless others.

The FATSO Jr sticks rigidly to the sound you know from the original hardware, delivering that immediate, familiar analog glue. For those who need more granular control, the FATSO Sr steps in, adding deeper ways to shape and manipulate the compressor's response for complex modern workflows.

Four Distinct Flavors of Compression

The FATSO doesn't just offer saturation; its compressor gives you four classic curves to choose from, allowing you to glue drums, buses, and full mixes together with as much or as little attitude as each song calls for:

• Buss: Utilizes a soft-knee 2:1 ratio to gently and transparently bind a mix together.
• G.P.: Quietly and effectively holds levels steady on just about any source you throw at it.
• Tracking: Takes its cue directly from the legendary 1176, perfect for bringing vocals and instruments to the front of the speakers.
• Spank: Channels the famously slammed, aggressive sound of the talkback compressors found in vintage ’70s SSL consoles.

Unmistakable Saturation for Every Source

At its core, the FATSO brings complex analog character to every source in your session. A light touch on the Input knob rounds off harsh transients and adds pleasing harmonics. Cranking it past the Pinned LED turns a drum bus dense, gritty, and incredibly aggressive.

For electric guitars, the transformer saturation adds beautiful grit, while the signature Warmth control rounds off the top end, taking the harsh edge off bright amp tones or sibilant vocals.

Moving Beyond the Hardware

UA didn’t stop at simply 1:1 recreation. The plugin introduces features you won’t find on the original hardware unit. Sidechain filtering gives you far more precise control over what the compressor actually reacts to, preventing heavy low-end from triggering unwanted pumping.

Native

Additionally, variable transformer saturation lets you control exactly how much iron color lands on a track. Best of all? You can now run the FATSO natively on your Mac or PC, entirely independent of a UA Apollo interface.

Pricing and Special Launch Offer

If you’re looking to add this to your toolkit, Universal Audio is currently running a massive limited-time offer.

Right now, you can get the UAD Empirical Labs FATSO for $79.00, saving $70.00 off the standard retail price. This discount is effective immediately and runs through November 1, 2026.

Key Features Summary:

• Authentic tape saturation and compression developed alongside Empirical Labs founder Dave Derr.
• 2 plugins in 1: FATSO Jr for iconic hardware tones and FATSO Sr for deeper compression control.
• 4 compression modes: soft-knee 2:1 Buss, steady-leveling G.P., 1176-style Tracking, and SSL talkback–style Spank.
• Input drive that pushes drums, bass, guitars, and vocals from soft clipping to thick, crushed distortion.
• Signature Warmth control and variable transformer saturation to tame harsh top-end and sibilance.
• Modern upgrades include sidechain filtering and deeper compression parameters.
• Native compatibility: Runs with or without a UA Apollo interface.

Our Thoughts

I’ve been putting the FATSO through its paces today tracking a heavy alternative mix inside LUNA and a mix in Logic Pro, and I have to say it's been an absolute lifesaver.

I'd already heavily overloaded this bass track through a tube front-end preamp in my studio, and it was huge. FATSO let it sit in the mix and keep the low end when I moved to smaller monitors. I also tested the mix on my iPhone, and the bass is still there.

Getting bass to sit properly in a dense, heavy track without losing its attack can be a nightmare, but dropping this onto the bass bus instantly built body and overtones.

It gave the low end a gritty presence that ensures it still translates perfectly on small speakers, while the Warmth control let me aggressively roll off the brittle top end of the heavy guitars without losing their bite. If you need something to quickly glue a mix together and add instant analog weight, the $70 discount makes it well worth it.

UA

More UA