ONE LA 500

Classic LA2A in your 500 series rack!

Two knobs of happiness.

The IGS ONE LA 500 is an opto-compressor built for the 500 series format. This is the first high voltage vacuum tube 500 series module that is offered by IGS. It is powered with 250V DC from an on-board voltage converter, so it can be plugged into any 500 series rack equipped with a standard power supply.

Every single ONE LA is hand made with high quality, matched components (1% metal film resistors, Wima caps). It is equipped with JJ tubes and individually calibrated to give you the unique and unspoiled experience of one of the best opto-compressors in the history - the Teletronix '68 LA-2A. We have spent hundreds of hours designing the ONE LA, to make sure that it is as simple to use as it is versatile. Not only for harmonically rich vocals and strings, but also for huge and beefy drums and bass instruments.

Using two ONE LA 500 as a stereo pair will allow you to use it as an excellent bus compressor!

There is something else.

Three audio transformers (IGS Custom in an audio path and OEP in sidechain) have been used to provide excellent performance and with only two knobs and a single compressor/limiter switch, there is nothing that could go wrong. Additionally, you can replace the photocell easily (special version available)

"No compromise device - all tubes are powered by 250V DC!"
  1. Videos
  2. Gallery
  3. Download
  4. Specification
  5. Reviews
  1. Device type
    Optical Compressor Yes
    Basic features
    Stereo Link Yes, for a custom order
    Hard wire bypass Yes
    Input & Output
    Input Impedance (balanced) 600 ohm, IGS Custom transformer
    Output Impedance (balanced) 600 ohm, IGS Custom transformer
    Audio transformers Yes, IGS Custom
    Operating Level +4 dBu
    Max input level +20 dBu
    Max output level +21 dBu
    Dynamic Range 100 dB
    Noise Level -99 dBA
    Max. gain 32 dB
    Max Gain Reduction 32dB
    Time constants
    Ratio 4:1 in COMP mode, 100:1 in LIM mode
    Attack: 10ms
    Release: 0.5 – 5s (50% @ 60ms)
    Frequency response 8 Hz - 20k Hz, +/- 1 dB
    Distortion (@ 20 Hz - 20 kHz)
    THD+N 0.002% @ 0dBu
    Front Panel
    VU Meters Yes, GR (backlit)
    Voltage API Standard, internal DC-DC conversion for powering tubes (250V DC)
    Power consumption 8.16W. Slot #1: 190mA@+16V, 170mA@-16V. Slot #2: 150mA@+16V, 0mA@-16V
    Packing box
    Shipping weight 3 kg
    Tube set ECC802, ECC803
  2. Files
    IGS LA500 user manual.pdf

      Working with opto-style compression (1) - by Tim Teissen.

      Opto compressors are said to sound very musical, especially when used with bass instruments and/or vocals. In my live rig, I’ve been using an opto compressor pedal for quite a while now, it makes my bass or guitar sound thick and warm, while preserving the punch of the instrument...

      Read more »


      Working with opto-style compression: mixing a song (2) - by Tim Teissen.

      As I promised (see my first post on the topic), I’m going to reveal some secrets about my last mix project. It’s kind of a DIY music video, made for my youtube channel. It’s an acoustic ballad, played by Julia Motz and me on two guitars. If you like our music, check out

      Read more »



      When I first came across IGS products, I was immediately taken by the care and precision these units are built with. It shows the people at IGS take pride in their work and stand by their products. A while ago I had the opportunity to spend some studio-time with an IGS ONE, basically their take on the legendary LA-2A design.

      Read more »