Arguably the coolest and most unique device in the Empirical Labs arsenal, the FATSO (Full Analog Tape Simulator and Optimizer) is a digitally controlled analog device that gives musicians and engineers easy access to many of the desirable characteristics exhibited by older tube and Class A electronics and magnetic tape mediums. This two channel audio processor musically integrates frequencies and transients, increasing the apparent volume while keeping tight control over peak levels.


With the FATSO, recording studios and audio production facilities can enhance and soften the sound of Hardware Digital Recorders (HDRs) and Digital Audio Workstations (DAWs).  Mix engineers will have the option not to have to use bulky, expensive analog tape recorders to get the warmth and sweet high end they’ve come to rely on for so many decades.  Owners of DAWs and HDRs can finally put a stop to complaints about the coldness and brittle edge of their mixes and instruments. Even audiophiles can benefit from the FATSO, bringing back the warmth and ambience of LP’s and tapes to their CD players and other digital reproduction mediums.









As with most Empirical Labs products, the unit is incredibly easy and fun to use. Large Distressor-style knobs control the input and output levels. Four meticulously tweaked compression modes - including the extremely popular “Buss” setting and the legendary “Spank”, a subtle knee followed by hard limiting resembling the SSL talkback compressor - can be selected (and combined!) with the push of a button.  Seven different high frequency saturation “Warmth” settings are accessed just as easily.  The FATSO also features switchable transformer circuits, which can add the musical artifacts generated by classic devices like NEVE, API, etc such as low order clipping and inter-modular distortion, transient clipping... and some other very musical non-linearities.  True to its name, the FATSO Jr. is rather sturdily constructed - you’ll be impressed with how well built it feels when you first lift it out of the box.


The FATSO Jr. has been the “secret weapon” of studio and live engineers for many years, allowing them to add the elusive magic of vintage gear to their sound.  Once you start using it, you’ll never want to be without it!

•  Harmonic Generation and Soft Clipper (Distortion Generation) - this class A circuit gently rounds the peaks like saturated tubes or tape.


•  High Frequency Saturation (Warmth) - a one-of-a-kind dynamic low pass filter which softens high frequencies when they “pile up” on a source.


•  Transformer & Tape Head Emulation - a simulation of the effect of input and output transformers of older devices, which adds  the low frequency harmonics that characterize them, as well as analog tape..


Classic Knee Compression - your typical automatic leveling device found on just about every instrument and vocal track as well as on  the overall buss, done Empirical Labs compression – smooth and sweet, but in your face!

Universal Audio’s FATSO Plugin

Endorsed and scrutinized for accuracy by designer Dave Derr of Empirical Labs, Universal Audio has painstakingly recreated the FATSO Jr. in this highly anticipated UAD Powered Plugin, capturing the sonic nuances of the original hardware. As part of the FATSO Powered Plugin, UA has also worked closely with Dave Derr to model the original concept of the FATSO, the FATSO Sr., with attack, release, and threshold compressor controls, among other features not available elsewhere.


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“In a word, the FATSO is a very good answer to what a lot of people loathe about digital recording. It smooths out the sharp, brittle edges to exactly the extent you choose, and fills in the hairline cracks just right. I use one on almost every mix I do. I could easily use one and quite possibly two more.” - George Massenburg



“The winner of the highly -coveted, “I’m going to write you a check right after the show award  was picked up by Empirical Labs for its FATSO processor”

- Craig Anderton, Pro Sound News



Best new Signal Processor-EQ AES Awards

“Empirical Labs Fatso took this category, despite the introduction of a variety of cool new processors. Who can resist the best aspects of analog tape combined with great compression” - EQ Magazine



 “The kick drum chain was pretty complex, and on the bass and keys, I used a variety of the old compressors, as well as six Fatso compressors chained together for the surround mix and the SSL console compressor for the 2-channel mix. They sound great; they are clean and variable and dynamic.”

- Kevin Shirley (on using the FATSO for Led Zeppelin’s recent 5.1 Live DVD)



All I know for certain is that I mixed a record through one recently, and ever since I’ve been at a loss to figure out what I’ m going to do without one.”

- Electronic Musician Magazine



 “People used to have to hunt for old, expensive gear to get the kind of sounds that the FATSO gives me.” - Ed Cherney  (Lenny Kravitz, Dave Mathews, Eric Clapton, The Wallflowers, Goo Goo Dolls, Jackson Brown, Bonnie Raitt, Stones, etc.)



“For over a decade the FATSO Jr. has had a proven track record of adding a warm fuzzy feeling to every buss and instrument it has ridden, and I will tell you the buss compressor alone is worth the price of admission.” - Recording Magazine


• Freq. Response is 2 Hz to 60 kHz in clean audio mode (+0, -3 dB).


• Dynamic Range 110 dB from maximum output (20%THDsoft clipping) to minimum output. Greater than 100 dB signal to noise.


• Distortion Ranges between .06% and 20% depending on mode and settings.


• DC coupled Input and Outputs


• High quality audio caps used internally. Compressor Time Constants - Attack range 1mS - 60mS. Release range .05 sec to 3.5 seconds. Attack and Releases are fixed by the compression type selected.