ECM-519 compressor



"Incredibly versatile compression and tone….this thing is deep!"
- Ryan Hewitt

Red Hot Chili Peppers, Blink 182, Tom Petty, The Avett Brothers

“The ECM-519 is a superb feedback fet compressor, with all the bells and whistles and then some. I’ve commonly used it just for the transformer selections for saturating digital audio material that needed some character. It’s stellar at adding snaps to drums, and the auto-modes work like a charm on finger picked acoustic guitar. And if I ever feel I’ve gone over the edge, the mix knob is there to bring me back to reality. It’s easy to see why it's nick-named the Empressor!”
- Dylan Dresdow

Black Eyed Peas, Michael Jackson, Usher

"It's really really good, it's quick as hell. You can really spank the living fuck outta stuff."
- Tim Gilles (Slipperman)

Thursday, Catch22, The Bouncing Souls, Taking Back Sunday

"The empress compressor is fantastic on drums, I love hitting overheads hard at 6 or 12 to 1 and pulling the mix knob back without using the transformer to keep it clean."
- Jonathan McMillan

Ellie Goulding, Stereophonics, The 1975, Jack Johnson

"what comes to mind immediately is musical, musical.. did I say musical!!"
- Ross Murray

Great Big Sea, The Mighty Popo

"The ECM-519 is nearly as versatile as a Distressor for half the price and space. Once again Empress knocks one out of the park. For the win."
- Mixerman

Foreigner, Ben Harper, Hilary Duff

"Since picking up my Empress 519 compressors, there is not a single session that I haven't used them on. I only wish I had more of them."
- Steve Foley

Kellylee Evans, J. Cole, Prairie Oyster



We've strived to design a feedback FET compressor with personality, that can excel where plug-ins fall short and seamlessly integrate with your DAW to add some often needed analog warmth. The pleasing FET harmonic distortion, and some transformer saturation options really help to add that analog character.

This compressor is extremely versatile. It's great on aggressive time settings and applying a lot of gain reduction, but can also be extremely transparent. The auto modes engage two completely separate side-chain circuits that change the way the compressor behaves, giving you sounds that aren't possible with conventional attack and release settings.

True bypass switching makes meaningful comparisons against the original signal quick and easy, and parallel compression is only a knob twist away. Happy squishing!

  • All Analog Signal Path - no digitals in here!
  • Selectable Output Transformer - Use the active balanced output for a pristine signal path or engage the output transformer for some added warmth. Load down the output transformer for even more old school analog character and some pleasant saturation.
  • 3 Ratios - 3:1 gives great transparent compression for evening out dynamics. 6:1 gives great control and can be pretty aggressive when doing lots of gain reduction. 12:1 is approaching limiting and can be very useful when you need to sit something in the mix or hit it hard for tons of character.
  • Super Fast Attack Speeds - Dial in attack speeds down to 50 microseconds! Great for controlling transients, and the beauty of FET based compressors.
  • Mix Knob for Parallel Compression - Blend in dry signal for New York style compression.
  • 10 segment LED Gain Reduction Meter - The very responsive meter lets you know what the compressor is doing.
  • Sidechain HPF - High pass the sidechain at 120 Hz or 220 Hz so the compressor doesn't react to the really low frequencies.
  • Auto Modes - These two modes employ completely separate sidechains. They both have two detectors that work together; one with really fast time constants at a higher threshold that reacts primarily to peaks, and a slower detector, with a lower threshold to smooth the overall signal. This allows the auto modes to provide extremely transparent compression that isn't possible with traditional attack and release controls.
  • Stereo Link - connect two units and link them as a stereo pair using either the link pin on your rack or the supplied link cable.
  • Analog Warmth - Engage the transformer and set the mix for 100% dry to use the ECM-519 for adding warmth without using the gain reduction circuit.
  • True Bypass - The Empress ECM-519 employs true bypass, so you can be sure that it's not affecting the signal when disengaged.


  Here's a review from Slipperman on the MixerMan show. They were discussing the "Empressor", which was the working title for the ECM-519 during the prototyping phase.


Slipperman Review



Input Impedance 48 kOhm
Output Impedance 50 Ohm (600 Ohm with transformer)
Frequency Response (-3dB) 10Hz - 35kHz
Power Consumption 120mA per rail
Height 5.25"
Width 1.5"
Form Factor API 500 Series 1U module
Output Level up to +22dBu
Input Level up to +22dBu
Attack Range (manual mode) 50us - 50ms
Release Range (manual mode) 50ms - 1s