The Brainworx bx_opto compressor combines some of the best colors, character and features from what Brainworx has learned modeling the optical circuits of some of the world’s best-loved compressors, like the Shadow Hills Mastering Compressor, the elysia alpha compressor, or the Millennia TCL-2.

But in this case, rather than re-recreating a hardware product in software, the bx_opto takes the best aspects and anomalies from legendary light-dependent Circuits to create a software compressor you wish you could buy in hardware!

Opto Compressors respond differently to different input signals, which is often referred to as being “program dependent”. For example, an opto compressor will react differently to a longer loud part of a song than to a short loud hit in a quiet part, as the photo cells will build up heat over time, which slows down the attack and release times significantly. With opto compressors, everything is moving constantly, and in an ear-pleasing way!

The musical characteristic that optical compression circuits possess, has made them a favorite of professional engineers for decades.

Next level Opto Compression

And Brainworx take the opto-concept to the next level with this plugin. bx_opto not only delivers that musical quality, but opens up new sonic possibilities with its variable speed knob, simulating changes in speed at which the photo cell in an optical compressor reacts to light. This gives you control over release times that shape transients in such a manner no hardware optical compressor can match.

Most optical compressors are appreciated for their musical, program dependent character introduced by anomalies in the light dependent circuitry of the sidechain; the general speed of compression is cemented by the given behavior of the compressor’s Light Dependent Resistor (LDR).

But hardware opto-compressors can only allow the user to adjust the effect of this character by introducing a separate resistance circuit that gives some control over the compression envelope.

After intense experimentation and listening tests, Brainworx found a way to adjust the compression envelope itself by allowing users to adjust the speed at which the LDR (Light Dependent Resistor) regains its dark resistance, producing a sonic character impossible to replicate with a hardware optical compressor.

Take a listen and be ready to fall in love with this red beauty.


  • Analog, optical compression colors with more control than hardware compressors can offer!
  • Truly Content-dependent peak reduction / compression
  • ‘Speed’ knob controls the coefficient of Light Dependent Resistor, creating unique transient response
  • Fully sweepable sidechain filters
  • Wet/Dry mix for parallel opto-compression

Audio Examples

Industry Reviews

  • Tony Vincent

    Tony Vincent

    Artist/Producer (Queen’s We Will Rock You, Green Day’s American Idiot, The Voice)

    I find myself using this on bass guitar habitually. It adds a presence and clarity that is completely its own.

  • Jody Wisternoff

    Jody Wisternoff

    Way Out West

    Lovely compressor, just sounds very natural and really glues the drum buss together nicely!!

Customer Reviews

  • good

    by nice
  • Nice

    by Ilker S.
    A simple to use opto compressor with dry wet regulator with low CPU consumption, price / performance fits
  • Easy and nice

    by Bunzing
    I love simple compressors that are free of artifacts. Using your ears, it's easy to dial in a sound you like in seconds. I find myself using it on more and more sources, but it's excellent on vocals… Read More
  • Clean

    by Mchangani
    I love the mojo it brings into a vocal chain. thick and warm
  • Great Compressor!

    by Joel
    This is a terrific and flexible opto compressor. Really a workhouse, it works well on just about anything you throw at it. I especially like it on brass, it tames trumpet perfectly. Great with… Read More


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

Supported Operating Systems
MacOS 10.9 through 10.14
Windows 7 through 10

Intel CPU only (minimum 2 GHz recommended)

Intel-compatible CPU with SSE2 instruction set (Pentium 4 compatible or higher; minimum 2 GHz recommended)

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


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