It seems fitting that Universal Audio offers the Capitol Mastering Compressor plug-in. When the first hardware units were made, Capitol Mastering engineer/tech Ian Sefchick [Tape Op #134] drew from his love of the Universal Audio 175 compressor and his desire to pair its tube front end with a solid-state back end. Named the CM5511, the unit has been used on more albums than one could swing a cat at, including releases from labels like Capitol, Blue Note, Motown, and Verve.

If Sefchick’s name seems familiar, it should be. He’s also the creator of the Magic Death Eye Compressor (modeled by DDMF [Tape Op #137]), which looks similar at first glance but is a different beast than the CM5511. With a nod towards Fairchild, Gates Sta-Level, and a dissimilar sidechain approach, the Magic Death Eye is a distant relative, not a competitor. Basically, I’m saying you’ll want both plug-ins. Sorry/not sorry about that.

The reason for the excitement surrounding this release begins with the original CM5511 hardware – or lack thereof. Only four units were made! I remember reading details in Capitol Mastering engineer Evren Göknar’s book, Major Label Mastering. The whole time I was thinking, “That’s just great, man. How in the heck could any of us use the darned thing?” It’s a win for the rest of us that Universal Audio worked on this plug-in so we can get our virtual hands on it.

The controls are straightforward, with the standard Input, Threshold, Attack, Release, and Output logically presented left to right. It runs in dual mono or linked stereo, as well as M/S. On the hardware, the link sets the right channel as the control, but the plug-in uses the left, which makes more intuitive sense. Large, circular VU meters monitor the user’s choice of gain reduction or level.

Universal Audio didn’t stop there, choosing to add expanded controls. A closer look at the plug-in’s main controls, and you’ll spot the Ratio control. It’s easy to miss. Not on the original unit, it looks like the recessed tweaker pots used for VU calibration. It’s stepped and cycles ratios from 2:1 up to 10:1. The remaining additions are grouped on a fold-out strip that expands from the bottom of the GUI. Mix can blend from no processing to 100% wet. Headroom steps from 4 to 28 dB in 4 dB increments, allowing adjustable gain staging (one of the most critical tasks engineers do – or should be doing). The Saturator adds harmonic content. You can blend in saturation with the Shape knob, with an available range of 0 to 100%. Other niceties include mono fold (adjustable from 20 to 200 Hz), digital meters, and dBFS/LUFS switching. Mix and Headroom affect the compressed signal only, while Saturator and Shape still process the signal, regardless of the Mix setting.

In use, I recommend instantiating it and to start messing with the knobs. I was able to get usable results without reading a stitch of documentation. That’s a testament to the original design. Spending time with the Attack and Release settings proves most valuable, as each of the five steps may respond differently than expected. I’ve found some compressors are very good at fast settings, but not slow, and vice versa. However, the Capitol Mastering Compressor sounds polished, regardless of speed. Choosing the best combination is always a must, but you’ll have a more challenging time discerning with this unit because even when it's set "wrong," it never really gets bad sounding, only less good. Oddly enough, I never adjusted the ratio from the default 4:1 and didn’t see a need to (based on the full mixes I used). It’s also important to spend time gain staging the input and output, as each affects the processing differently(obvious to most, but worth noting).

In a mastering context, the compressor can give that sounds-like-a-record finish. But when I let it run wild, I learned this compressor loves submixes and individual tracks. Having Mid-Side for drums kept the stereo space in check without making the drums sound mushy. On snare drum, I found a killer use for the Saturation control. Increase it until you hear more crunch that feels right, then back it off a bit. Instant anger in a box. For an R&B female vocalist, the CM5511 provided almost invisible control, smoothing the performance without conveying a “hey, that’s compressed” dehydrated sound. While one set of backing vocals seemed to get dull, notably decreasing the clarity as they sat in the mix, another test recording was improved. Using aggressive compression settings blended at 40% subconsciously filled in the meat of the vocals while preserving the dynamics and high-frequency content. It wouldn’t be unreasonable to suggest the Capitol Mastering Compressor could find a place on every mix.

Thankfully, Universal Audio are some of the absolute best when it comes to recreating hardware in the digital realm. The Capitol Mastering Compressor is no exception. This plug-in combines the sound of the hardware with the additional power of features such as Saturator, Mix, Headroom, and Mid-Side, making it a compelling addition to any plug-in collection. Whether one spends most of their time mixing, mastering, or tracking, this plug-in can suit any taste or objectives. Along with the Distressor plug-in [Tape Op #126], this is by far my favorite dynamics plug-in Universal Audio makes.

Tape Op is a bi-monthly magazine devoted to the art of record making.

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