Electro Optical
The U2A is a homage to what is rightfully considered the ultimate opto compressor of all time. It celebrates the bold minimalism and beautiful nonlinearities which built the legend, while providing unique access to system relevant component conditions for unconventional flexibility and control.

Through the Decades
In the analog world, there is a wide variety in how the individual hardware units sound and behave due to physical aging effects. The U2A makes use of this phenomenon, allowing you to blend from a freshly serviced unit with a new opto cell, and an age-old vintage device in its original state. Meanwhile, the near magical program-dependent release character of the T4B attenuator can be tweaked with an individual knob.

Two in One
The U2A assigns makeup gain and THD injection to separate controls, so opto compression and tube saturation can be adjusted independently of each other. Rounded off with onboard parallel processing and the usual suspects like the infamous R37 sidechain filter network and a limiter mode switch, the ultimate tool for beefy and most musical leveling just got… complete.


  • A homage to what is rightfully considered the ultimate opto compressor of all times, based on sophisticated analog modeling with a couple of nifty tweaks.
  • The Aging parameter solves the hardware reference question: Based on a new machine - or an old one? The U2A can be both, and the user is given access to the resulting effects with just a single knob.
  • The natural behavior of the T4B opto cell is the key for the ultimately smooth and natural leveling characteristics of LA-2A based designs. There’s nothing better if the fixed scheme fits, but not much of a chance if it doesn’t. The Recovery knob adds a lot of flexibility in terms of timing to the tried and trusted design.
  • Two audio processors in one: The U2A decouples the dependence of the degree of saturation generated in the tube amplifier stage from the actual amount of make-up gain being set. Now, compression and saturation can be used completely on their own, or in a glorious combo to easily achieve that unique fat compression everybody loves.
  • Of course, the U2A offers a mix control for onboard parallel compression/saturation. All of the beautiful effects described above can be added to the original signal just in little doses or full on.
  • Ease of use: Compression doesn’t get any easier than with an LA2A. The additional features have been created honoring exactly that spirit: A single control for each function, hiding all technological complexity under the hood.

Audio Examples

Industry Reviews

  • Joe Carrell

    Joe Carrell

    Mix / Recording Engineer

    I like the idea of reimagining a classic to be better and even more usable. That’s what I find in the U2A. It does exactly what I would want and expect, but with the twist of newer fresher… Read More

  • Tom Van Den Heuvel

    Tom Van Den Heuvel

    Mixing Engineer

    When the organic tone of the most iconic opto compressor meets such levels of flexibility you enter a new world of musical possibilities, and that's what makes the U2A priceless!

Customer Reviews

  • Great for fatten up your project

    by BluelagoonStudios
    I use the U2A since it came out, very easy to use, and paired with a black Box HG-2 a great combination, if you like a saturated sound, I even have a setup where I use the Opticom XLA-3 together with… Read More
  • oh my god

    by Pexou
    A very usefull compressor so undless mojo when you put it hard
  • U2A is ThE WAY!

    by Kenok
    This is my absolute FAVORITE Opto compressor at the moment!! I'm in LUV with it's lush, thick but freely-customizable sound! It's effortless!... I used it for mastering a debut track recently and it… Read More
  • very accurate

    by Sergio Frias
    So i just tested this one to the uad LA-2A (silver) using plugindoctor and i can match the same curves ,theres only a slight difference at the 100 hz area , r37 is also a match, i left the… Read More
  • Spectacular

    by Mario Blankenberg
    NEOLD did it again. A sensational box that makes for a larger than life sound. The "Aging" function gives me a crystal clear and beautiful analog tilt towards the low-end.


Supported Plugin Formats
AAX Native, AU, AAX AudioSuite, VST2, VST3

Supported Operating Systems
macOS 13 down to macOS 10.11
Windows 11 down to Windows 8

Intel or Apple Silicon architecture

x64-compatible CPU

System Requirements
Display resolution: 1440 × 900px or 1280 × 960px or higher
Memory: 2 GB RAM




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NEOLD U2A - Changelog

Version 1.0 (Apr 27, 2023)
- Initial released version