Compressors are one of the most commonly used tools of the audio engineer. Although every compressor on the market essentially performs the same function of controlling the volume dynamics of the source, each compressor has a unique way of coloring the sound going through it and engineers lean on different models to bring the best out of any given instrument. Stereo compressors are simply compressors with two channels that can either be linked together such that each channel behaves similarly, or used as two independent compressors with different settings. Stereo compressors are exceptionally useful for processing stereo groups of signals (like the drums) or even the entire mix.
At Rarefied, we now have quite a few different stereo compressors, each with their own unique flavor of sound.
First up is the Neve 33609JD
The Neve 33609 compressor/limiter is a classic. I personally love it on drums, but it really can be used on anything. The design of this unit is based on the Neve 2254 going back to 1969. The JD version (vs. just the J) has a discrete output stage that is often preferred. You can go pretty heavy with this compressor without hearing many artifacts, but its hand-wound transformers impart an immediate tonal benefit to the input.
Next we have the ADR Compex (Re-issue)
The Compex is another classic loved for drums again. Apparently this compressor was used on the iconic “When the Levee Breaks” drums. The Compex is a bit more complicated to use than many compressors, with its expander/gate options and built in limiter, but with much patience comes great returns.
And here’s the Smart Research C1
The Smart C1 is a clone of the modern classic SSL G-Series bus compressor. This compressor was built into certain SSL consoles and quickly was found to really glue the entire mix together when used on the whole stereo bus. It can really tighten up the low end of a mix too. Alan Smart, the companies founder, actually worked for SSL for a time, servicing and installing many of their consoles around the world.
The AnaMod AM660
Rarefied has two of these unique 500 series compressors (thus making a stereo pair). Founded by Dave Amels (Bomb Factory, plug-ins), and Greg Gualtieri (Pendulum Audio, fine tube gear) AnaMod set out to do something very different in the Pro Audio world. Taking the same modeling approach used by the plug-in world, these two industry vets applied this process in the analog domain. It’s kind of strange to say that it is an analog model of analog gear, but that’s exactly what it is. The AM660 goes after the sound of the classic Fairchild 660 compressor which is no longer made and costs a small fortune to procure in good working order today. Just like plug-in manufacturers, they modeled the behavior of the Fairchild mathematically, but instead of implementing a DSP implementation of the model they used analog circuits to achieve the same thing (but without the many exotic tubes and transformers of the original Fairchild).
Here’s the odd-ball Standard Audio Level-Or
Another pair of 500 series compressors, these guys are based off the Shure Level-Loc. The Level-Or is a very aggressive compressor that pumps and breathes in often unruly ways. The Level-Or sound is definitely for effect and can hardly be called subtle. The “Crunch” mode is a special feature that unleashes less compression and more pure distortion and overdrive to your signal. Crunch is great for adding even more distortion to guitars and “Level” mode is great for making things get weird.
And now the Orban 424A
Orban was much more active in the Broadcast market so this compressor would probably more likely to be found in a 70’s radio station than in a studio. However, it still makes for a great compressor! The 424A is definitely colorful, not only in body, but in sound. It also incorporates a gate and de-esser which was probably put in for broadcast vocal duties.
And last, but not least- the Valley Audio Dynamite3
This is the 3rd iteration of the Dynamite line from Valley Audio. Valley Audio has also made gear under the names Allison Research, Valley People, and Valley International. The original Allison Research brand was founded by Paul Bluff who worked in the studio with Frank Zappa. After moving to Nashville, subsequent design work led to the patent of a Voltage Controlled Amplifier (VCA) circuit which is what gives the unique sound to the Dynamite line. The Dynamite has become known for how it can really add aggression to drum tracks. If you need your kick and snare to cut through a dense mix of heavy guitars, the Dynamite is up to the task.