Digitally Controlled Analog Knee Compression

The product that started it all for Empirical Labs. Born of founder Dave Derr’s love of classic compressors like the 1176, LA-2A and Gain Brain (among others), the Distressor incorporates his favorite sonic characteristics of these, along with other unique and interesting features that have made it a staple for audio engineers all over the world. With over 38,000 units in the field, it’s safe to say that the Distressor is one of the best selling high end compressors of all time… if not THE best selling. A prominent recording engineer recently wagered that there probably was not a top 40 record made in the last five years that didn’t have at least one Distressor on it.

Besides providing a wide range of control and a unique feature set, the Distressor offers a warm, vintage sound by using a custom designed gain control circuit. This “warmth” or “vintage sound” has become a major issue in the last few decades, as the super clear and linear digital technology does next to nothing to soften “harsh” sounds, nor emphasize the bass frequencies in music sources. Conversely, older analog tape, vinyl records and tube equipment could not be prevented from coloring the sound, often to the frustration of recording engineers. However, many people now realize that this coloring can be extremely pleasant and musical. Digital technology is often referred to as “cold” and “brittle” among other terms (although we prefer “unforgiving”).

The EL8-X (top) is the new and improved version of the EL8 (bottom). The EL8-x includes Stereo Image Link and British Mode switches. An EL8 can be upgraded to an EL8-X. Click here for more information.

Unique Compression Curves

All eight of the Distressor’s curves are unique and distinctive, from the 1:1 mode that simply warms up signal with low order harmonics without intentional compression, to the “Nuke” setting – a brick wall limiting curve that shines on live drum room mics. Each curve has its own personality and several actually use different circuitry, and are effectively different compressors. Most exceptional is the 10:1 “Opto” ratio which uses separate detector circuitry to emulate the oldest (and valued) “light controlled” devices, such as the LA-2A.

Distortion (Color) Modes

Another large part of the Distressor’s personality and power derive from three modes that color the signal, even without compression. These extended audio modes were designed to allow emulation of some very old and expensive vintage compressors & limiters, and let the Distressor deliver a classic “knee” sound all its own by providing user programmable, warm harmonic distortion. In addition to the basic distortion mode, Distort 2 emphasizes tube-like 2nd order harmonics, while in Distort 3 setting the distortion becomes dominated by 3rd harmonics more closely resembling tape. Two HP filters – one in the audio path, one in the detector path – are also available to help with low frequencies that can cause pumping and breathing.

Go Stereo

For many Distressor owners, one is never enough – in fact, one extremely successful engineer has twelve of them! For those who want (at least) a stereo pair, ELI offers the EL8-S, a pair of Distressors that are matched at the factory, and come with the cables you need to lock them together. If you want the Brit Mod and Image Link options, an EL8X-S package is also available.

British Mode - EL8-X

The concept of British Mode came from an unusual setting on the classic UREI LN1176 limiter. The unit was designed to have only four ratios, each ratio being engaged by selecting one of four buttons. However, as early as 1980 (or before), renegade recording engineers, always on the lookout for something a little more “over-the-top”, found that you could make all four buttons stay in if you pressed them just right. What resulted was a very aggressive sound that had some elements of the unit’s 20:1 ratio, but with an unusual knee and new envelope shape. Somewhere along the line, someone called it “British Mode”, and the name stuck.

The EL8-X has the advantage of being able to selectively apply this aggressive characteristic – not just to the new “British” ratio (1:1) – to any of the ratios, simply by engaging the dedicated “British Mode” switch.

The British Mode and Image Link options are only available on the EL8-X. Click here to learn more about upgrading your EL8 to an EL8-X.

Image Link - EL8-X

The original Distressor stereo link function used a summing and phase detection method, which allowed slight stereo image shifting. Although frequently desirable for its phase correction, and its “thickening” on open room mics and other stereo sources, this approach can sometimes be a problem on stereo program material where the producer/engineers want to maintain absolute left/right balance at all times. With the new “Stereo Image Link” option, the EL8-X now has three link options – the original “phase” link, the new Image Link and the combination of the two, phase and image linking – something never before offered on any compressors or limiters.


  • Frequency Response – 2 Hz to 160 kHz in clean audio mode (+0, -3 dB). Response is shaped in distortion modes (Dist 2, Dist 3).
  • Dynamic Range – 110 dB from max. output to min. output in 1:1 mode. Greater than 100 dB signal to noise in distort 3 mode.
  • Distortion – ranges between .02% and 20% depending on distortion mode and release times set on front panel.
  • I/O – DC Coupled input and outputs.
  • Time Constants – Attack range 50uS – 50mS. Release range .05 sec to 3.5 seconds, normal modes and up to 20 seconds in 10:1 opto mode. Time constants are dependent on ratio.
  • Power Consumption – 15 Watts Max.
  • Metal Chassis – single height 1.75″ high, 10″ deep, 19″ wide.
  • Shipping info – 12.1 lbs mono, 24.2 lbs Stereo pair. Mono box dimensions 22.5″ x 18.5″ x 3 1/4″. Stereo Pair box dimensions 22.5″ x 18.5″ x 6 1/4


Upgrade to an EL8-X

New EL8-X Metal Face Plate
British Mode Switch Modification
Stereo Image Link Modification

Stereo Pair Upgrade

New EL8-X Metal Face Plates
British Mode and Image Link Switch
Both units are matched as a stereo pair

All upgrades include a 24-hour burn in, full QC and unit test for the latest specifications, and free shipping back within the continental United States.


The type of distortion the Distressor produces isn’t supposed to be heavy guitar amp type distortion.  It was designed to sound like the somewhat grungier circuits from the early days of audio, when designers had to kick and scrap to get 1% THD (Total harmonic distortion) out of a tube or transistor.  Whereas today, a 30 cent op amp IC today can get .002% THD  without even trying!  However, the old tube and Class A transistor distortion often had this pleasing “bite” or urgency to it. Our goal with the distortion circuits in the Distressor, was to allow the user to recover some of this vintage “bite”.

There are ways however to make the distortion more obvious.  First, slowing up the attack will let the peaks hit harder and soften the compression, allowing hotter operating levels around the distortion generators.  Quickening the release can sometimes do the same thing since it “sucks” up the signal back to hot levels after it is done compressing a signal.

There is no limit to how many units can be linked – in theory. However, you must avoid long link cables since they will cause noise and degradation of operation. To wire up more than two units, go from the link output of the 1st unit’s link to the next units link input, then take that units link out to the next ones input etc. Finally, take the last units link out and feed it back to the first units link in. Again, your must use stereo phone plugs for the new “Stereo Image Link” to work.

Use this ratio to “skim” peaks. This means that most of the time it may not be doing anything, but when it does “hit” the signal, it will smoothly push back the signal and then get right out of the way again. If you are hitting the Gain Reduction all the time with the British mode on, you are going to be really “squashing” the signal. On the other hand, the Distressor will sound fairly subtle when compressing all the time in 2:1 mode, especially with a slower attack (>6).


Magazine Reviews


“The Distressor is probably the most adaptable compressor ever made, and used properly, sounds great on almost anything.”
Bob Power
A Tribe Called Quest, D'Angelo, Bobby McFerrin, etc.
“The most impressive and versatile compressor I have ever used”
Michael Brauer
John Mayer, Coldplay, The Fray, etc.
“The unit is really awesome! I’ve used it on guitars, bass, room mics, vocals it works great on everything. I’ve used it on records I’ve made with Beck, U2, Etta James, Hole and lots of others. I’m about to buy a second one.”
Joe Chicarelli
U2, Beck, Peter Gabriel, etc.
“A really good sounding vocal compressor. Guitars, Drums. Everything. You can’t have too many Distressors.”
Tchad Blake
James Bay, Tom Waits, Sheryl Crow, etc.
“The Distressor would be the last piece of hardware many engineers would relinquish; you’d have to pry it from their cold, dead hands, as the saying goes”
Pro Sound News

Software Versions

The Arousor™ is the only native Distressor plugin made by Empirical Labs. Rather than it being an emulation of the world famous compressor, it is an evolution on its great features. With uniques features such as the AtMod™ and Advanced Detector Sidechain, this plugin is not an imitation; it’s innovation.

The UAD EL8 Distressor is the only emulation officially endorsed by Empirical Labs. This product is only compatible with Universal Audio Devices and is distributed by Universal Audio.

Related Articles

Stereo Image Link Tips and Tricks

The original Distressor stereo link implementation used a summing and phase detection method which allowed stereo image shifting.
Read More

Brit Mode Tips and Tricks

The original concept of the “British Mode” came from an unusual setting on the classic UREI LN1176 limiter.
Read More