We’re currently living in the age of digital audio, and in-the-box mixing within a digital audio workstation is commonplace. Plugins are, therefore, invaluable assets for the modern audio engineer. There are plenty of plugins that aim to emulate analog hardware in an attempt to make digital audio sound more like its [arguably] nicer-sounding analog counterpart.
There are plenty of excellent analog optical compressors and plugin emulations of such compressors. With so many options to choose from, I’ve compiled what I consider to be the 10 best optical compressor emulations plugins.
What is an optical compressor? An optical compressor is an analog compressor that uses a light element and optical cell to alter the dynamics of an audio signal. As the amplitude of the audio signal increases, the light element emits more light and causes the optical cell to attenuate the amplitude of the output signal.
For more information on optical compressors, check out my article What Is An Optical Compressor & How Does It Work?
The top 10 best optical compressor emulation plugins for digital audio workstations are:
- Softube Tube-Tech CL 1B
- Cakewalk CA-2A
- Native Instruments VC 2A
- IK Multimedia T-RackS Opto-Compressor
- Waves CLA-2A
- Brainworx bx_opto
- Audiority LDC2 Compander
- Brainworx Shadow Hills Mastering Compressor
- Universal Audio Teletronix LA-2A Collection
- Variety Of Sound ThrillseekerLA
It should go without saying that any “top X” article is subject to bias. I would expect the next person’s top 10 to be different than mine but hope that there would be plenty of overlap.
That being said, I believe these plugins to be the best optical compressor emulation plugin options today. The criteria I used to judge these plugins include the following:
- Sonic performance: how does the optical compressor emulation plugin sound subjectively/objectively?
- Graphic user interface (GUI): how does the optical compressor emulation plugin look when loaded in the DAW?
- Ease-of-use: how user-friendly is the optical compressor emulation plugin?
- Functionality: how many different functions does it serve and/or how many parameters are available for the optical compressor emulation effect?
- Accessibility/compatibility: how easy is it to acquire the optical compressor emulation plugin, and what are the system requirements?
Let’s discuss each of the top 11 best optical compressor emulation plugins in greater detail to learn why they made this list.
Softube Tube-Tech CL 1B
The Softube Tube-Tech CL 1B (link to check the price at Plugin Boutique), as the name would suggest, is an emulation of the world-famous Tube-Tech CL 1B optical compressor.
The Softube Tube-Tech CL 1B is compatible with Mac OS and Windows OS and comes in AAX Native, AAX DSP, AU and VST formats.
Since 2006, Softube and Tube-Tech’s partnership has brought forth many superb plugins. This CL 1B brings the warm, punchy analog sound of the original and is truly a modern classic.
This optical compressor plugin is a complete ground-up model of the CL 1B compressor. From the sound of the software to the graphic user interface, this plugin is spot on. In addition to the original controls, Softube has included extra features to make this compressor’s legendary character even more versatile.
The standard features are plentiful in this opto compressor emulation. Dial-in the Output Volume, Ratio, Threshold with virtual continuously variable knobs. Set the attack/release controls to one of three settings and fine-tune the time constants with their own virtual knobs.
To learn more about compressor ratio, threshold, output (makeup) gain, and time constants, check out the following My New Microphone articles:
• Dynamic Range Compression: What Is The Ratio Control?
• Dynamic Range Compression: What Is The Threshold Control?
• Dynamic Range Compression: What Is The Makeup Gain Control?
• Dynamic Range Compression: Attack & Release Controls
Select what the VU meter will display (input, compression or output) with a 3-way knob and choose whether the sidechain signal is internal or external.
The parallel blend and side-chain low cut are now standard features on many compressor plugins. Softube offers both features for easy parallel compression and improved compression detection, respectively.
This plugin is also capable of mid-side processing (along with stereo processing), making it even more versatile in DAW applications.
For more information on system requirements and authorization instructions, check out the Softube user manual.
Softube is featured in the following My New Microphone articles:
• Top 11 Best Audio Plugin (VST/AU/AAX) Brands In The World
• Top 11 Best DAW Control Surface Brands In The World
Tube-Tech is featured in My New Microphone’s Top 11 Best Audio Compressor Brands In The World.
The Cakewalk CA-2A (link to check the price at Cakewalk) is a T-Type Leveling Amplifier plugin modelled after the legendary Teletronix LA-2A.
The Cakewalk CA-2A is compatible with Mac OS and Windows OS and comes in AAX, AU, VST and ProChannel Module formats.
Cakewalk has meticulously modelled the Teletronix LA-2A to program an opto compression plugin that offers the same silky smooth sound as the legendary hardware unit. From the optoelectric gain reduction circuit to the 4 vacuum tubes, this plugin is spot on.
The limited controls of the plugin make it super easy to use, and, like the original, it sounds great on pretty much everything. From tracking to mixing, this zero-latency plugin performs incredibly well.
Choose a softer or harder knee for this largely program-dependent compression via the Compress/Limit switch. Adjust the high-end with the expertly-modelled “R37” HF Pre-emphasis control. Dial-in the Gain and Peak Reduction knobs for the perfect amount of compression and meter one of four options in the virtual VU display: GR (gain reduction), dBFS (decibels full-scale), +4 dB or +10 dB.
To learn more about decibels (dB), check out my article What Are Decibels? The Ultimate dB Guide For Audio & Sound.
This superb compressor plugin offers up to 40 dB of transparent frequency-dependent compression with relatively slow program-dependent time constants (attack and release times). Choose between Classic & Fast Reset modes to control the release time to some extent.
The modern functionality of external sidechain control has been included in this amazing optical compressor plugin.
To learn more about compressor sidechain, check out my article The Complete Guide To Sidechain Compression In Audio.
For more information on system requirements and authorization instructions, check out the CA-2A at Cakewalk.
Native Instruments VC 2A
The Native Instruments VC 2A (link to check the price at Native Instruments) is one of many emulations of the classic LA-2A Leveling Amplifier/optical compressor hardware to make this list.
The Native Instruments VC 2A is compatible with Mac OS and Windows OS and comes in AAX, AU, and VST formats.
Native Instruments’ VC 2A is an easy-to-use and sonically accurate emulation of the legendary Teletronics LA-2A. It’s part of the Vintage Compressors collection that has come about from the successful Native Instruments and Softube collaboration.
Along with the classic program-dependent attack and release controls, this slow-response compressor an external sidechain input with a variable low-cut (high-pass) filter in the detector path.
Described as smooth and silky, the electro-optical tube compression and limiting of the NI VC 2A is as musical and “vintage-sounding” as the original hardware it aims to emulate.
For more information on system requirements and authorization instructions, check out the VC 2A at Native Instruments.
Native Instruments is featured in the following My New Microphone articles:
• Top 11 Best Virtual/Software Instrument Plugin Brands
• Top 11 Best MIDI Controller Brands In The World
IK Multimedia T-RackS Opto Compressor
The IK Multimedia T-RackS Opto-Compressor (link to check the price at Sweetwater) is an optical compressor emulation plugin that affords all the characteristics of an opto compressor without specifically mimicking a specific hardware unit.
The IK Multimedia T-RackS Opto Compressor is compatible with Mac OS and Windows OS and comes in AAX, AU, VST and RTAS formats.
We’ve already spent some time describing the character of optical compression with terms such as “smooth”, “silky”, “transparent”, “slow,” and “vintage”. The T-RackS Opto-Compressor captures all these adjectives in a fantastic stereo opto compressor plugin.
IK’s proprietary DSM and SCC modelling have been used to recreate the distinct analog sound of optical compression, though, as we’ve discussed, this plugin isn’t a direct clone of any particular hardware.
This plugin offers 6 simple controls: Input, Ratio, Attack, Release, Compression and Output. Dialling in the perfect amount of opto compression is made easy. There is no distortion or coloration during gain reduction, and the compression is of a gentle, transparent, and organic sonic nature.
In typical T-RackS fashion, The Opto-Compressor is designed for operational mode with both L/R and M/S channels. Choose linked or independent channel sidechaining with the Link switch.
For more information on system requirements and authorization instructions, check out the T-RackS Opto Compressor at IK Multimedia.
IK Multimedia is featured in My New Microphone’s Top 11 Best Virtual/Software Instrument Plugin Brands.
The Waves CLA-2A (link to check the price at Waves) is a third emulation of the famous LA-2A Leveling Amplifier.
The Waves CLA-2A is compatible with Mac OS and Windows OS and comes in AAX, AU and VST formats.
This plugin version of the LA-2A features all off with Chris Lord-Alge’s personal presets, offering a variety of ready-to-go smooth frequency-dependent optical compression options.
Like the original, the CLA-2A has both compressor and limiter modes, a high-frequency sidechain filter, and Gain and Gain Reduction knobs. This super-simple zero-latency plugin presents users with the same beloved character of the original 1960s Teletronix unit.
Users can choose to engage Analog modes in either 50 Hz or 60 Hz for realistic mains hum in the output signal. The VU meter can be set to meter the input, gain reduction or output amounts.
With low total harmonic distortion, variable release times and a distinct program-dependent compression style, the Waves CLA-2A is a top choice for those in need of an audio plugin version of the classic LA-2A.
For more information on system requirements and authorization instructions, check out the Waves CLA-2A user manual.
Waves Audio is featured in My New Microphone’s Top 11 Best Audio Plugin (VST/AU/AAX) Brands In The World.
The Brainworx bx_opto (link to check the price at Plugin Alliance) is a superb opto compressor emulation plugin that offers the best characteristics of optical compression without aiming to recreate the sound of any particular unit.
The Brainworx bx_opto is compatible with Mac OS and Windows OS and is available in AAX DSP, AAX Native, AU, AAX AudioSuite, SoundGrid and VST formats.
Brainworx is one of the best when it comes to modelling hardware and creating world-class plugin emulations. The bx_opto compressor is one such example of the superior modelling, and painstaking attention to detail Brainworx is known for.
Taking the best aspects and anomalies from top-performing optical compressor circuits, Brainworx has developed a sonically masterful software plugin.
This musical compressor features the typical peak reduction and output controls. The Speed knob adjusts the compression envelope, altering the attack and release times of the virtual gain reduction circuit. A Mix knob makes for super-simple parallel compression without the need for any mix buses.
The sidechain signal can be manipulated even further with fully sweepable sidechain filters (choose between high-pass, low-pass, band-pass and bell).
To learn more about HP, LP and BP filters, check out the following My New Microphone articles:
• Audio EQ: What Is A High-Pass Filter & How Do HPFs Work?
• Audio EQ: What Is A Low-Pass Filter & How Do LPFs Work?
• Audio EQ: What Is A Band-Pass Filter & How Do BPFs Work?
For more information on system requirements and authorization instructions, check out the bx_opto at Plugin Alliance.
Brainworx is featured in My New Microphone’s Top 11 Best Audio Plugin (VST/AU/AAX) Brands In The World.
Audiority LDC2 Compander
The Audiority LDC2 Compander (link to check the price at Plugin Boutique) is a unique opto compressor emulation plugin.
The Audiority LDC2 Compander is compatible with Mac OS and Windows OS and is available in AAX, AU, and VST formats.
Audiority’s LDC2 Compander offers warm, analog-sounding optical compression and expansion with a variety of modelled optical circuits, solid-state diode-based preamplifiers and output stages. Mix and match the following for optimal optical compression:
- 17 real-time optical circuit models
- Fixed ratio (4:1) Optical Compressor (max. GR of 40 dB)
- Fixed ratio (3:1) Optical Expander (max. GR of 30 dB)
Dial-in the compression even further with independent side-chain gain and high-pass filters and utilize the Mix control for easy parallel processing. With zero-latency performance, this plugin is a superb choice for tracking, mixing, mastering and live performances.
For more information on system requirements and authorization instructions, check out the Audiority LDC2 Compander user manual.
Brainworx Shadow Hills Mastering Compressor
The Brainworx Shadow Hills Mastering Compressor (link to check the price at Plugin Alliance) is a plugin emulation of the superb Shadow Hills Mastering Compressor hardware.
The Brainworx Shadow Hills Mastering Compressor is compatible with Mac OS and Windows OS and is available in AAX DSP, AAX Native, AU, AAX AudioSuite, SoundGrid and VST formats. It can also be run on UAD hardware.
The Brainworx Shadow Hills Mastering Compressor is also featured in My New Microphone’s Top 11 Best VCA Compressor Emulation Plugins For Your DAW.
The Shadow Hills Mastering Compressor is an impressively powerful optical compressor and is revered as the “godfather of dynamics control.”
Brainworx has meticulously modelled the legendary hardware circuitry of the Mastering Compressor and has produced one of the greatest compressor plugins on the market in doing so. The plugin has been approved and endorsed by the founder of Shadow Hills Industries, Peter Reardon.
Of course, adding this plugin to this list is a bit of a stretch. Since it has both an optical gain reduction circuit and a VCA reduction circuit, it’s not a “true” optical compressor emulation plugin. That being said, putting it last on the list, we could consider it as a bonus plugin after the “top 10” we’ve already discussed.
Sending the signal through both compression stages is a large part of the Brainworx Shadow Hills Mastering Compressor charm. Adjusting both these stages offers superior control over signal dynamics. With a bit of fine-tuning, this compressor will sound amazing on any source material.
Select between three different modelled output transformers to add extra character to the signal. Nickel adds high-end sparkle, Iron adds mid-range character, and Steel adds additional harmonic distortion.
The Brainworx Shadow Hills Mastering Compressor works in either stereo and dual-mono modes. Each compression stage features all necessary compression parameters.
In addition to all that functionality, Brainworx went ahead to include Parallel Mix control, a Sidechain Filter and an External Sidechain option in the proprietary toolbar. These controls further enhance an already incredible compressor plugin!
To get through all the features of this incredibly powerful plugin, I’d need a whole other article. Please consider checking out the Brainworx Shadow Hills Mastering Compressor user manual for all the information you’ll need.
For more information on system requirements and authorization instructions, check out the Shadow Hills Mastering Compressor specifications at Plugin Alliance.
Universal Audio Teletronix LA-2A Collection
The Universal Audio LA-2A Grey | LA-2A Silver | Original LA-2 (link to check the price at Plugin Boutique) are plugin emulations, recreating the variations in character across multiple versions of the legendary Teletronix/Universal Audio LA-2A.
The Universal Audio LA-2A plugins, like all UAD plugins, require UAD hardware to function with your DAW. UAD hardware is compatible with Mac OS and Windows OS, and the plugins are available in AAX, AU and VST formats.
This superb bundle of UAD plugins is the definitive plugin collection of the most famous LA-2A compressor versions. The history of Universal Audio and Teletronix goes all the way back to the 1960s, as both companies were acquired by Studio Electronics Corporation (which would eventually be rebranded as UREI). Bill Putnam, the founder of Universal Audio, is even credited with manufacturing the Silver version of the hardware.
Universal Audio’s first release of a plugin version of the LA-2A came in 2001, which set helped set the stage for the company to become one of the biggest names in audio plugins today.
Since then, UAD’s modelling has become much more precise, and today the company offers the most authentic emulations of three distinguished versions of this iconic compressor.
This bundle offers 3 distinct versions of the legendary Teletronix optical compressor:
- LA-2A Grey: manufactured by Jim Lawrence, this version has average time constants, providing excellent medium-speed compression.
- LA-2A Silver: manufactured by Bill Putnam (founder of Universal Audio), this flexible plugin has relatively fast time constants (for an opto-comp). It is suitable for a wide variety of program materials.
- Original LA-2: from the early 1960s, this rare model offers the slowest response and a uniquely mellow style of compression.
Select the best option for your applications and enjoy some of the greatest vintage compression ever in the flexibility of your digital audio workstation.
For more information on system requirements and authorization instructions, check out the UAD Plug-Ins Manual.
Universal Audio is featured in the following My New Microphone articles:
• Top 11 Best Audio Plugin (VST/AU/AAX) Brands In The World
• Top 11 Best Audio Interface Brands In The World
• Top 13 Best Microphone Preamplifier Brands In The World
• Top 11 Best Audio Compressor Brands In The World
Variety Of Sound ThrillseekerLA
The Variety Of Sound ThrillseekerLA (link to check the price at Plugin Boutique) is a freebie and a rather loose emulation of the LA-2A optical compressor.
The Variety Of Sound ThrillseekerLA is compatible with Windows OS and comes in the VST format.
This free stereo levelling amplifier plugin offers non-linear analog sonic qualities similar to the renowned LA-2A.
For a variety of smooth feedback compression styles, adjust the Input, Attack, Release, Range (similar to threshold) and Output knobs. Engage the SC Low-Cut switch to remove low-end information from the sidechain for a more concise triggering of gain reduction. An additional 6dB/octave SC low-cut filter adjustable from 20 to 500Hz with a virtual knob.
To learn more about feedback compression, check out my article Feedback Vs. Feed-Forward Dynamic Range Compressors In Audio.
This modernized plugin features external sidechain support along with a variety of colour-inducing options. Adjust saturation in a designated spectrum by engaging an optional modelled transformer and control the amount of total harmonic distortion with a horizontal slider. The Interstage switch offers even more subtle distortion to the output.
For more information on system requirements and authorization instructions, check out the ThrillseekerLA at Variety Of Sound.