We’ll thoroughly examine the seven best VCA compressor plugins and 2 free plugins you can find in 2023 in VST, AU, and AAX formats.
Every engineer since the eighties has relied on VCA compression to glue their mixes together. It’s not uncommon to hear producers refer to that “glue” sound as the SSL sound, as it’s probably the most famous compressor in the world. However, there are other options out there, and we want to show you a few of the best. Let’s dig right in!
The 7 Best VCA Compressor Plugins 2023 (VST, AU, AAX)
1. Cytomic The Glue
The Glue, By Cytomic, is designed to provide your mixes with that final punch and tightening.
Inspired by SSL 4000 hardware, The Glue is a clear-sounding plugin with a wide array of applications. Whether in compressing single tracks, busses, or entire mixes, this plugin will give you enough versatility to create the industry’s tried-and-true bus compression effect.
An excellent addition that wasn’t part of the original circuit is the Side-chain function, which allows you to either use internal or external sources at selectable frequencies across the entire spectrum.
- Range Knob
This control limits the amount of compression without considering the threshold value, making for a more natural-sounding result. It is a way to countermeasure the fixed several fixed control voltages present in the original hardware design. You can use the other parameters in this compressor to achieve hard compression and then use the range knob to dial it back to the sweet spot.
- Peak Clip
This button engages a waveshaper with zero attack and release times, medium knee, and infinite ratio. It cuts out the peaks at -0.5dB and audibly distorts the sound. If you have the MakeUp gain too loud, it will generate a harsh sound on the transients. The best alternative is engaging the Peak Clip when the Range knob is also active so that the compressor stops overreacting to the transients and leaves enough room for the Peak Clip to work smoothly.
The Glue offers up to 16 times real-time oversampling, which expands the sample rate to a maximum of 705.6 kHz. You can use these options while mixing and monitoring. It will introduce latency and increase CPU usage, but it will give you a more precise definition of the high frequencies. Alternatively, you can choose to oversample when rendering. Here you can go up to 64 times, or 2.8 MHz, for incredible frequency clarity.
- Factory Presets
The Glue comes with 14 categories and 80 presets – it’s great especially for drums, guitar, vocals, mastering.
Character & Sound:
The Glue offers genuinely transparent sound, with the classic grit of VCA compression. If you push it too hard, it will distort, especially with the Peak Clip engaged. The plugin comes with a collection of astounding presets for drums, bass, guitars, strings, keys, lead and backing vocals, side-chain, and mastering.
These are very helpful when you need a hand to find a starting point for your compression but can sometimes convert into set-and-forget settings. You can always fine-tune these presets into something that precisely fits your track.
This plugin is available as AU, AAX, RTAS, VST for macOS 10.8 and above and Windows XP or later.
The Glue is an outstanding alternative to the classic SSL-4000 sound due to its increased versatility. You will find yourself using this compressor in numerous busses and instruments, but it also does what the name proposes, effortlessly gluing your entire mix together.
This plugin is an attractive addition to your collection of VCA compressors.
2. Softube VCA Compressor
Softube VCA Compressor is a virtual audio plugin designed to replicate the sound and character of vintage analog compressors.
It features a classic VCA compressor design with various unique features, including a mix knob, a sidechain high-pass filter, and an external sidechain input. The plugin also includes a variety of presets designed for different types of audio material, as well as extensive controls for customization.
- Classic VCA compressor design
With its classic VCA compressor design, the plugin emulates the sound and behavior of vintage analog compressors, delivering smooth and transparent compression. This process accurately captures the tonal characteristics, dynamic response, and hardware saturation, resulting in a warm and transparent sound.
The plugin’s controls behave like their hardware counterparts, offering you the same level of control and flexibility. It is a popular choice for producers and engineers seeking classic analog compression in their digital recordings.
- Mix knob
You can achieve a more natural and dynamic sound with the plugin’s unique mix knob, which blends compressed and uncompressed signals.
- Sidechain high-pass filter
You get a sidechain high-pass filter, which allows you to control which frequencies trigger the compression. This feature provides greater control over the sound, allowing you to apply compression more selectively and achieve a cleaner, more focused mix.
- External sidechain input
The plugin includes an external sidechain input, which enables you to trigger the compression with an external source, such as a kick drum or bass guitar. This feature provides even greater control over the sound and allows for more creative sound design possibilities.
You get a variety of presets designed for different types of audio material, such as vocals, drums, and guitars. These presets can be used as a starting point for customization and provide various options for achieving your desired sound.
- Customization controls
There are extensive controls for customization, including attack, release, ratio, and threshold controls, as well as a makeup gain control for adjusting the overall output level. These controls provide a high degree of flexibility, enabling you to create unique and complex soundscapes.
Softube VCA Compressor is compatible with major DAWs on both Mac and Windows systems that support AAX, VST, and AU formats.
The plugin recreates vintage analog compressors’ tonal qualities and characteristics. Its features, such as the classic VCA compressor design, mix knob, sidechain high-pass filter, and external sidechain input, provide smooth and transparent compression with customizable controls.
3. Waves SSL G-Master Buss Compressor
The SSL G-Master Buss compressor is a direct emulation of the original compressor found in the SSL 4000 desk.
The plugin attempts to emulate the classic sound of the SSL 4000, which is present in most of the music released by major artists since the console’s creation.
Attested by countless mix engineers the world over, the original hardware is now sold in several formats, and the Waves plugin leaves nothing to be desired, except maybe the feel of turning the actual knobs.
You can engage this function, which will create different fade forms, depending on the number of times you click the button. By default, the control is set to Fade Off. When you click it, it becomes Fade Out, and if you toggle it again, it becomes Fade In. The Rate-S button above determines the amount of time in seconds that the fade will take to occur. This function is great to use with automation when you want to create a fade effect in an instrument or on the entire mix, for that matter.
Some people say this button is absolutely useless, but there’s a good reason for its existence. This button allows you to use the compressor using a transparent or more dirty approach. It’s a very subtle difference, though. What happens is: as the G-Master Buss Compressor was modeled after the original hardware, Waves faithfully recreated all the components. Activating the Analog button makes these components operate similarly to how they would on the actual desk, which causes noise and harmonic distortion. Disengage this feature if you’re looking for the compressor’s effect but not its characteristic sound.
Character & Sound:
The classic SSL sound has generated several emulations from different developers and manufacturers. The Waves plugin has a thorough representation of the original unit paired with several presets by the people who actually use it.
Overall, this is a plugin that adds a lot of texture to your sound, whether it’s drums, guitars, vocals, or the master bus. It has a gritty quality and a round bottom end that sounds great pushed to extremes or just adding that classic glue.
This plugin is available for Windows 10 64-bit and macOS 10.13 and higher in VST, VST3, AAX, and AU formats.
The SSL G-Master Buss Compressor, by Waves, carries the same sonic and visual characteristics as the original from which it has sprung. If you’re looking for a sworn-by sound for your final mixes, this must be your pick. It’s a user-friendly plugin with an unmistakable sound.
4. Arturia Comp VCA-65
Arturia’s Comp VCA-65 emulates the classic DBX 165A compressor that offers extended side-chain controls, unique sound and is rich in presets.
The DBX 165A was one of the most thorough compressors of its time and has become a staple in professional recording studios since its release. The distinct character of the original hardware has been faithfully translated to the digital realm by Arturia.
The plugin sounds fantastic on drums, pianos, guitars, and anything that needs an extra punch.
- Auto Attack and Release
One of the most exciting features of the original hardware was the Auto switch. It enabled the Attack and Release functions to be adjusted according to the input material. It sounds especially sweet on vocals and acoustic instruments, taking the compression to the smoother side due to its variable attack rate.
- Advanced Side-Chain
The VCA-65 offers fully-featured side-chain parameters that accept three input sources: Internal, External, and Manual. The last one lets you trigger and automate the side-chain without the need for an input signal. Additionally, the plugin offers high and low pass filters and an SSL style EQ, which you can use to tame sibilance. You can also change the compression range from soft to extreme.
- Time Warp
Located in the Side-Chain section, this knob ranges from Snap to Loose, and it introduces a lookahead function to the compressor when turned to the Snap side. However, when turned in the opposite direction, you can make the compressor respond even slower than the slowest attack time. These are advanced features that make this plugin the most versatile on our list.
Character & Sound:
If punch and presence are what you’re after, this VCA compressor gives them gladly. On a drum bus, it simply breathes life and pressure like no other VCA plugin. Additionally, you can make the plugin sound like it’s not even there by just adding enough glue to hold the sound together in “Over Easy” compression mode.
This parameter is basically what modern compressors call a “Soft Knee,” and you can achieve it by keeping the compression knob between 1 and 1.5. Furthermore, if you want to spice things up, this compressor also brings in a Limiter mode that tames only the loudest peaks and adds beautiful vintage saturation.
This plugin is available for macOS 10.13 and higher and Windows 8.1 and up in 64-bit VST2.4, VST3, AAX, and AU formats.
Arturia’s VCA-65 is a must-have in your collection. In fact, it is one of the very few plugins without which you can’t live. If you had to choose only ten compressor plugins to use forever, this should be one of your top picks. That’s why it’s on our list. It is a versatile VCA compressor with straightforward controls and a whole lot of character.
5. Tone Empire Model 5000
Tone Empire’s Model 5000 combines two classics: APIs 2500 and SLL’s 4000 bus compressor.
As far as emulations go, this plugin is an intense blend. By studying and recreating the circuits of 2 of the most sought-after VCA compressors, the developers promise to deliver the best of glue and thrust to your mixes. The digital signal processing engine focuses on creating a natural analog feel without disregard for clarity and quality. The plugin offers up to 8 times oversampling, which sounds pristine on the higher frequencies.
- Knock Circuit
The heart of the plugin’s sound, KNOCK delivers a punchy side-chain with variable slopes, selected through the FREQ knob. The frequencies all have a different Q, which makes each sound unique. It’s not a very versatile option, but as with most VCA compressors, it delivers the unit’s sound. You can add weight to the tone by turning the LIFT knob, which will boost the selected frequency. Here is also where you’ll find the oversampling options of two, four, and eight times.
This part of the plugin was modeled after the rasping sound of the bus console it emulates. It engages an input and output transformer to generate the whole semiconductor sound experience. As you push up the Input Gain knob, the harder the saturation. You can go up to 24dB of input gain, and by pressing the TRANSX button, it generates a drive. Parallel processing is achievable with the left-most Mix Knob, which introduces the dry signal as it’s turned to the right.
- Auto Gain
This tiny, almost hidden switch turns the Auto Gain circuit on or off. It is controlled by the threshold knob and designed to add gain compensation post-compression. As you turn the threshold knob to the right, more gain is added to the output. It will be better used if you’re making some extreme gain reduction and don’t want to lose overall volume.
Character & Sound:
The Model 5000 sounds familiar yet unique. It is not as versatile as the API and not as specific as the SSL. Somehow, it has managed to be a hybrid that incorporated some of the tone and punch of its predecessors and added its own twist, which is excellent.
The ability to choose how much grit or tone you want to incorporate makes it an improved-sounding version of the originals. It has borrowed the SSL parameters, which makes it feel more like a bus compressor. Even so, you can use it for single instruments as well.
This plugin is available for macOS 10.13 and higher and Windows 10 in 64-bit VST3, AU, and AAX formats.
By bridging some of the differences between two famous VCA compressors, the Model 5000 by Tone Empire offers a great deal of character paired with capable compression. It sounds like neither of the originals it has modeled its style after, so it’s a worthy addition to your collection even if you already have the classics.
6. IK Multimedia T-Racks Bus Compressor
IK Multimedia T-Racks Bus Compressor is inspired by the mix bus VCA-type compressor from a renowned British mixing console of the ’80s, with added enhancements.
It is a module within the T-RackS CS “Custom Shop” Mixing and Mastering Plug-In Collection. The compressor is known for its transparent and character-enhancing qualities, particularly suitable for drums and bass. It offers high-quality oversampling, precise digital processing, and versatility within the T-RackS CS Standalone application and as a plugin.
The T-Racks Bus Compressor is favored for its ability to deliver polished, professional sound across genres like House, Pop, Hip-Hop, and more. Sonically, it is also known for its ability to add punch and power to tracks or full mixes, with a focus on achieving commercial loudness while maintaining dynamics.
The Sidechain Hi-pass filter in the plugin allows you to avoid the undesirable low-end pumping effect that can result from high ratio and low threshold configurations. Despite being a fresh feature, it aligns with the original unit’s design, featuring predefined values and curves. Four frequency choices—60, 150, 250, and 500 Hz—are available, enabling focused adjustment on the lower frequencies and low-mids.
- Mid-Side Processing
This T-Racks enhancement introduces another dimension to this highly sought-after bus compressor. Operating in Mid-Side mode facilitates distinct compressions for each channel. By toggling the switch below the prominent RESET button, you can establish independent settings for each channel. You can also compress it in L/R or multi-mono modes.
- Gritty sonic characteristics
Also developed as a new addition, this feature amplifies the plugin’s inherent character to emphasize harmonic distortion. It operates subtly but aims to replicate the behavior of imperfectly calibrated hardware—a quality sought after in specific scenarios.
- Versatile and modern-sounding
T-Racks suit a wide array of musical genres and excels even with delicate styles like Acoustic or Classical. It successfully marries the original unit’s sonic attributes with contemporary adaptability, substantially expanding its potential applications.
- “Gluing” effect
Accurate measurements from individual components to compression curves, soft knee response, and detection circuitry have been applied on this compressor behind the scenes. That ensures an exact replication that imparts a sense of unity to mixes, often recognized as the “glue effect.” This effect harmoniously blends each instrument, transforming mixed tracks into a cohesive musical composition.
- Attractive interface
The black-greyish skin of the compressor gives the right feel. Other than that, it has a dB meter, LUFS scale, Peak, RMS, and Direct Reduction readings, and L/R stereo volume scale for monitoring the plugin. Lastly, with parameters like Ratio, Attack, Release, Threshold, Makeup gain, Sidechain hi-pass, and Grit button, you can easily tweak things around and set the effect as per your liking.
The T-Rack Bus Compressor is available as a 64-bit VST2, VST3, AAX, and AU plugin for Windows 7 and up and macOS 10.9 or newer.
The Bus Compressor is a lovely plugin to have around, especially if you’re mixing more commercial genres like Pop and Hip-Hop. Using it on the master track will give your sound that polished, professional feel for which most of us are looking. That is an excellent plugin that will sit perfectly in your collection.
7. brainworx Vertigo VSC-2
Modeled after yet another classic unit, the Vertigo VSC-2 by Brainworx is a faithful recreation of the original VCA compressor.
With two voltage-controlled amplifiers per channel, the Vertigo VSC-2 was a staple of bus compression back in 1979. The Brainworx plugin offers a model of the same circuitry and attempts at revisiting the time period when the quad discrete VCA compressor ruled. The prolonged-release times offer vintage dynamic compression, while the Soft mode works as an automatic ratio.
- Dual Mono
The plugin’s two channels offer the ability to use it as a dual mono compressor. The advantage of flipping the switch is a broader and more independent stereo image. That is caused by the two slightly different compressions happening simultaneously. Alternatively, you can use the plugin in stereo with linked parameters.
- Soft Mode
The smallest ratio option is called Soft. Even so, it is not what most of us would think a soft knee and ratio relationship would likely be. In other words, Soft mode enables an automatic variable ratio that increases depending on the input level. That makes it simply impossible to make a ratio mistake since it rides the transients and compresses them accordingly. Short peaks will have a 1:1 compression, while louder ones can go up to 8:1 reduction.
Character & Sound:
The VSC-2 offers very audible compression; therefore, it’s a simple plugin to use and understand. You will know when it’s compressing too much or when you have just found the right amount. Indeed, it sounds “vintage,” but not because it adds distortion.
The plugin has an evident sound signature, which is also a trademark of the VCA circuit, but which is very apparent on this particular plugin. That makes it a great plugin to add compression and coloration to your mixes, busses, or single instruments.
The Vertigo VSC-2 is available for macOS 10.9 and newer and Windows 7 and up as a VST2, VST3, AAX, RTAS, and AU plugin.
As it can range from soft compression to limiting, this VCA compressor offers a little more versatility than the previous ones on this list. The sound signature is apparent but not as harsh as the other plugins, too. In the end, all this makes the VSC-2 a classy unit, desirable for its tone and ease of use. You can’t go wrong with getting it for your collection.
The Best Free VCA Compressor Plugins
1. Analog Obsession BUSTERse
Analog Obsession’s BUSTERse plugin can be your main tool for “gluing” mixes.
Now, what do you use the bus compressor for anyway? First, it allows you to shape transients, and second, to get the effect of “gluing” the mix as a whole. The SSL Bus Compressor is a very popular equipment for this, which was part of the console. But now, there are enough plugins that emulate its operation.
Such is the free software BUSTERse from Analog Obsession. Its main feature is that, in addition to the compressor settings, it has many additional features that will help you affect the character and dynamics even more. Let’s now try to take them all apart.
- Familiar Compressor Settings
If you already have experience with SSL-style compressors, then the set of basic settings will not discourage you. In particular, there is the usual Auto Release, Ratio from 1.5 to 10, Attack from 0.1 to 30 milliseconds, Make-Up Gain, and Threshold control.
- Dry/Wet Control
Unlike many paid plugins, the developers have also implemented the Mix knob, which implies selecting the ratio of Dry and Wet signals. This parameter can be very helpful if, for example, you want to do a parallel compression for drums.
- Additional Mods
At the top right of the plugin window, you will get three buttons that are responsible for mods. In particular, the first Main will work like the usual bypass. Also, here is the Turbo, which will bring the plugin to work more similarly to the original unit. And in addition, there is an Xformer mode to get more saturation.
- Sidechain Filter
The Sidechain section makes your work with the plugin most exciting. You can use it to influence how the compressor perceives frequencies. For example, there is a High Pass Filter here and two Mid and HF knobs.
- Transients Shaping
On top of that, the Sidechain section has another set of TR controls to help you influence the transients a bit more. For example, you will find a Tilt control that will boost the high frequencies and cut the lows, or vice versa. In addition, there are also separate Mix and Boost knobs.
Analog Obsession BUSTERse is available for Windows 7 or higher and macOS 10.9 or higher. It comes in VST/3 and AU formats.
Analog Obsession’s BUSTERse plugin may seem a bit complicated at first. But if you learn how to use it, it can become a powerful tool for bus compression. This software will allow you to “glue” the mix and influence the transients in the best way. And the fact that it’s free is wonderful.
2. Sender Spike SN01-G
Sender Spike’s SN01-G is a free VCA compressor for Windows inspired by two classic hardware units.
The minimalistic looks hide the full power of this plugin’s sound. It excels at bus compression, as expected from its SSL/API inspiration. The three available Modes and Push options make it a versatile plugin, but the hidden secret behind its sound is the Topology Switch.
The Mode knob changes the side-chain filters. There are three available modes: A, B, and F. Mode A shelves the high end and adds a slope cut to the lows, preserving the mids. On the other hand, B creates an upward EQ line from -12dB at 20Hz and +12dB at 20kHz. If you want to bypass this section, simply turn the knob to F, which means “Flat,” and will apply no side-chain filtering.
You can use the plugin in its standard compression rate or choose to go to extremes with the Push knob. Here you have the options Zero, One, and Two. Zero bypasses the effect, while One lowers the threshold by 9dB and Two doubles that amount, reducing the dynamic range even further.
- Topology Switch
On the left-hand side of the GUI lies a small switch that holds a power no other plugin on this list possesses. Inspired by the Old/New switch on the API 2500, the SN01-G lets you change your topology from Feed-Forward to Feed-Back. That causes the plugin to work in two absolutely different ways, which increases its versatility significantly.
Character & Sound:
The developers insisted on adding no coloration engine, which means no saturation or, in their words, “digital fakery.” All you get is straight-up the compression sound. This makes the SN01-G a clean-sounding compressor, but it doesn’t decrease its punchy character.
Sender Spike’s SN01-G is a Windows-only VST plugin.
This plugin offers the classic sound of VCA compression with versatile functions at zero cost. So if you’re not willing to make a financial commitment to acquire any of the previous plugins on this list, rest assured you’ll have your needs fulfilled by this fantastic tool.
Unfortunately for Mac users, this is an advantage for all the PC people out there. Download this plugin to have the punchy sound of VCA for free.
CFA Sound GRIP By Resonance Sound
GRIP, by CFA Sound, borrows the circuitry of vintage tube compressors but is designed to perform as a VCA workhorse.
With a particular valve drive section and precise parameters, GRIP stands in a league of its own within our list. The compressor attempts to blend modern-sounding VCA technology with old-school Tube emulation for warmth and character.
Therefore, its sound is unique and its flexibility remarkable. Moreover, the 2x oversampling and user-friendly design make it a powerful ally for your mixing.
- Valve Drive
This section gives you control over the essential aspects of coloration to make the result suit your production the best way possible. Changing the Input value will directly shape how the tube colors the sound. The drive knob gives you up to 24dB of valve character, while Bias emulates the amount of passive current drawn by the tube, affecting the tone. Finally, the blend knob lets you dial back on the overall valve emulation if you want a cleaner sound. The two tube modes, Triode and Pentode, have very different characteristics as well. The first gives the sound musical even harmonics, while the second adds odd harmonics, thus further increasing the crunchiness of the signal.
- Compressor Blend
This knob lets you further manage the proportion between the drive signal and the compression effect. You can use this to bypass the compressor entirely if you happen only to want the sound of the valves. Alternatively, you can turn it all up to Wet mode and turn the Valve Blend knob back to dry, and bypass the valve. However, you’ll achieve the most interesting results when you strike the perfect balance between the three signals: dry, tube-driven, and compressed. That is when this plugin truly shines.
Character & Sound:
With the extensive set of controls that CFA’s GRIP gives you, it’s hard to get a bad-sounding record out of it. This plugin’s parameters allow you enough range to set the compression as fast and robust as you want. The ratio goes up to 20:1, and the Recovery function lets you dial up to two seconds of release time.
That is especially great if you’re using this plugin on a master or drum bus to give you the prolonged flavor of the compression, just as engineers of olden times used to do with their tube compressors.
This plugin is available for Windows XP or later and macOS 10.6 or newer in VST and AU formats.
This plugin’s tagline, “Compression with Character,” does not lie. It does give you enough warmth to be used within your mixes or on your master bus. The plugin also has a few interesting presets to show you a starting point of manipulating the drive and compression for the best results.
Overall, this is an excellent addition to your collection. It’s a plugin like no other on this list for a fair price.
Whether through classic hardware or independent designs, the sound of VCA compression is a staple of the recording industry. Since the early eighties, mixing and mastering engineers have relied on voltage-controlled amplification to give their work a final cohesive sound.
We expect you have found your go-to plugin on our list, but if you’re still in doubt, here’s an overview: The Glue, T-Racks Bus Compressor, and the SSL-G Master Buss Compressor are all modeled after the original SSL 4000 bus compressor.
The closest to the original is the Waves plugin, so if you’re into authentic historical sounds, go for it. The other two have slight differences from the original design, but they sound very similar. The Glue is the most versatile option, while T-Racks offers M/S processing, which can be very helpful.
However, Model 5000 is a blend between the SSL and the API 2500, making it around the same league as the plugins mentioned above, but with a slightly different, unique sound. The VSC-2 is a solid and powerful VCA compressor plugin that is useful for various applications.
The GRIP has the warmest tone on the list due to its extensive valve recreations, and the VCA-65 is the most versatile VCA compressor plugin there is. Finally, the free SN01-G will solve all your problems if you’re on Windows.
Pedro Nascente is an artist, record producer, and mix engineer, currently operating his own studio and working with his band, Yellow Boulevard. Believing that music should convey experiences and feelings, Pedro is known for applying design thinking to his workflow to achieve different sounds and deliver the right messages.