When it comes to injecting character into the mix, compressors can play a pretty big role when they’re not being used for plain old dynamic control.

Here we take a look at three ‘clean’ compressors for transparent dynamic massaging, and three characterful comps for more creative flavourings. In this context, by clean we mean those devices that do dynamics and not much else. Our character compressors, by contrast, were designed to do the same but deliver classic sounds by way of their mid-twentieth century foibles. We also look at a modern classic that could do the work of nearly all of them…

Clean Compressors

1 - Massenburg Designworks MDWDRC2

First we kick off with a tool that might be less on every engineer’s radar. But if we’re talking about clean transparent control of dynamics, few can equal George Massenburg’s MDWDRC2 (Dynamic Range Controller 2). Noticeable in this list for not calling itself a compressor, it still does what its predecessors have always done: reduce the difference between loud and quiet. It’s just that MDWDRC2 is different to the rest thanks to its humanistic detection and potential for both upward and downward treatments.

That’s not to say that MDWDRC2 can’t be set to stun. It’s just that this remarkable tool does that, as well as doing undetectable-yet-purposeful, and everything else in-between. If you’re not afraid of taking the time to read the manual in more than one pass, fully comprehensive dynamic delights await you…

2 - Softube Weiss DS1-MK3

Before the DAW revolution, digital boxes were a thing. For some they still are, especially on time-based effect duties, but digital compressor/limiters in a box also exist. OK, you often only get a couple of instances, and you might have to sell all your other gear to afford one. That said, the ones that have survived can still lay claim to some of the most powerful, cleanest compression on the planet. It turns out that DSP hardware processors have been outrunning analogue for longer than some might think.

While most developers’ recreations of hardware comps claim total authenticity, Softube’s Weiss DS1-MK3 can actually lay claim to (almost) being the very same thing as its exotic digital hardware muse, with code ported directly from the unit itself. Spread out across four audio plugins in one (DS1-MK3, MM-1 Mastering Maximizer, Deess, and Compressor/Limiter) Softube’s suite of Weiss precision could be the best 2U you’ll never fill.

3 - SSL 4K E Channel

Yes, this one’s a whole channel. Although no analogue compressor is perfectly linear, numerous VCA designs that started to appear in the 1970s got engineers pretty close. This has made it a popular design on both channel and bus duties, with predictable, repeatable results that didn’t impart too much of themselves on the audio.

SSL’s 4K E compressor is nestled among an entire channel strip with other goodies, and if you’re looking for simple dynamic control for tracks, one of studio audio’s best known channel compressors will not disappoint. It does the whole gamut of tasks for tracks from light dynamic shaping through to full-on squashiness, with the added bonus of adjustable auto makeup gain offset as well. There are tonnes of other trusted E Series channel recreations to choose from, but this one is from the people who made the real thing in the first place.

Three Compressors For Character

1 - Plugin Alliance Brainworx ACME Audio Opticom XLA-3

Inspired by a bona fide studio classic, we kick off our character selection with an audio plugin that is a homage not to the Teletronix LA2A itself, but to its supercharged hardware protege, the ACME Audio Opticom XLA-3. The LA2A’s transformer-and-valve chunkiness is for many the epitome of the vintage opto compressor sound. Anyone who made a circuit with a battery and a lightbulb at school will instantly understand the ‘2A’s time constants which could be described as a bit relaxed…

Taking the Opticom XLA-3’s refinements on the LA2A theme, Plugin Alliance’s Brainworx audio plugin version delivers its Amp Mode and three compression response speeds, with the former allowing it to be used on ‘tone box’ duties without the gain reduction. Unlike either the LA2A and Opticom XLA-3, the virtual one has the ultimate mod hiding in plain sight: you can run one of them in stereo and have as many as you like!

2 - Arturia Comp DIODE-609

Although optical, variable mu, and FET designs are the stuff of legend, another type has been for more than the past fifty years no less of a presence in record making: the diode bridge compressor. These compressors became popular as a faster alternative to opto designs, with some unintended odd-harmonic colour helping to edge sounds further forward.

Arturia’s Comp DIODE-609 sets out to bring the Neve 33609 sound to the DAW. Going further than the original, Arturia’s creation has more comprehensive options for sidechain EQ-ing as well as mid-side stereo processing available. Although the original was developed to sit across mix outputs, it has a shared lineage with Neve’s console channel compressors, making it useful for tracks or busses. That could make it a good match for elements in need of anything from subtle rounding to the broad-brush gloopiness that diode bridge compressors can do so well.

3 - Overloud Comp670

Any compressor Hall Of Fame has to include at least a handful of units, and one of those is Fairchild’s uber- desirable 670 compressor limiter from the early 1950’s. For the uninitiated, this is the variable-mu valve limiter driven by World War II tech that inspired countless audio plugin homages with a broadly similar virtual design: build a valve amp, and use valves for the compression as well. Oh, and make it as big as a small fridge and so expensive (now) that you’ll need to sell your house and/or internal organs to afford one. These things reportedly sound so good that those with access will run audio through them for their revered tones whether they need its compression or not.

We’re spoiled for choice on which developer’s 670 to choose, however one interesting option is Overloud’s Comp670. Going one further than many of the Big Girls’ and Boys’ offerings, this one has sidechain filtering and parallel control as well. No two units were ever the same so how do you model an authentic one? Simple, just model three and let the user switch between them in Comp670…

The One That Does Them All?

FabFilter ProC-2

It could be said that modern developers have the luxury of drawing upon decades of revered compressor designs. There are plenty of beautifully rendered GUIs complete with rusty screws and chipped paintwork as testament to that, and by all accounts these creations usually have sounds to match the look.

Other software houses offer solutions that strive to be themselves, with some going further with offerings that can bring desirable dusty delights from the past, coupled with forward-looking (or should that be forward-feeding) dynamic control. One venerable tool that has found a home with many is FabFilter’s ProC-2. Whether you wear a labcoat or a kaftan to work, not only does this one do itself via Clean mode, but also just about everything else thanks to seven other modes that should keep everyone happy.

FabFilter Pro-C2 Modes:

• Clean - An all-round, low distortion, feedforward, program dependent style originally from Pro-Cv1.

• Classic - Also from Pro-Cv1, a vintage, feedback, very programme dependent style.

• Opto - Pro-Cv1’s relatively slow, very soft knee, more linear opto style.

• Vocal - Algorithm designed to bring vocals to the front of the mix, said to work well with automatic knee and ratio settings.

• Mastering - Designed to be as transparent as possible, introducing as little harmonic distortion as possible, while still being able to catch fast transients.

• Bus - The Fabs describe this as “especially great for bus processing, or for adding a pleasant glue to your drums, mixes or tracks”.

• Punch - Traditional, analogue-like compression behaviour, which FabFilter describe as sounding good on anything.

• Pumping - Deep and “over-the-top” pumping, great for drum processing or EDM.

How About You?

What are your favourite comps that inform your sound or simply keep your dynamics in check? Maybe you use some of the hardware that inspired some of these devices, or perhaps there’s another software compressor that you can’t live without. Let us know in the comments.