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Crate Audio CPL2 Stereo Compressor/Limiter

I have recently noticed a renewed trend toward improved design and quality disciplines involving Crate's products, and was intrigued when the Soundscape CPL2 stereo compressor was dropped at my door.

(click thumbnail)Fast FactsApplications: Sound reinforcement

Key Features: Two-channel; compressor/limiter with expander; Interactive Ratio Control; Breath processor; auto function

Price: $169

Contact: Crate Pro Audio at 314-727-4512,

Product Points


+ Quiet Operation

+ “Breath” processor restores lost high frequency content

+ Solid construction

+ Price


– Tricky expander threshold control

The Score:

A well-built low-noise stereo compressor/limiter/expander with some added bells and whistles at an ultra low price. St. Louis Music (now owned by Loud Technologies) has been a purveyor of musical instruments for more than 80 years, and their Crate division has been cranking out electronic instrument amplification for 25 of those years. After a brief flirtation with the Audio Centron line of professional sound reinforcement products, St. Louis Music decided to fold the Audio Centron line into Crate Audio.

Decidedly aimed at the MI market, they design products for the music stores and MI catalog houses of the world. However, I have recently noticed a renewed trend toward improved design and quality disciplines involving Crate’s products, and was intrigued when the Soundscape CPL2 stereo compressor was dropped at my door.


The CPL2 is a dual-mono compressor, which can be linked for stereo applications. A look at the front panel reveals the prominent features. From left to right, you will find expander/gate threshold control with LED indicators, -40 dB to +20 dB compressor/limiter threshold control, 1:1 through infinity:1 ratio control, 0.1ms to 200ms attack time control, manual/auto mode switch, 0.05s to 4s release time control, -20 to +20dB output control, enable/disable button, and a “breath” control. Next is the true RMS detection stereo/mono mode switch, and then the second channel of the unit, which mirrors the aforementioned functions. The manual/auto, enable/disable, and mono/stereo mode switches each have LED function indicators, and each channel has 12-segment 1 through 30dB LED gain reduction meters. The master power switch resides at far right.

Around to the rear jackfield, we find from left to right an IEC AC power socket with fuse housing, channel two’s balanced 1/4-inch TRS phone and XLR output jacks, +4 dBu/-10 dBV input sensitivity range switch, balanced 1/4-inch TRS phone and XLR input jacks, and duplicate jacks/switches for channel one.

Two items I noticed straight away while going through the CPL2’s features were the “breath” processor and the expander/gate function. The “breath” processor is claimed to add high-end clarity to the signal post-compression that will compensate for a perceived loss in this area, which they call dynamically controlled frequency correction. The expander/gate section features IRC (Interactive Ratio Control), which is claimed to continually adjust the expansion ratio and attack time to match incoming program material characteristics. I was anxious to try these accommodations in a real-world environment.

In Use

I decided to try the CPL2 in my project studio, utilizing signals that typically need compression: electric bass and vocals. I plugged my ’67 Fender Jazz bass into a Radial JDV direct box, from there into a Mackie 1604 VLZ mixer, and inserted the CLP2 into the channel strip. Monitoring the resulting signal through AKG K240 sealed headphones, I initially noticed that even with the expander dialed off and the output set at maximum that the noise floor was very low, good considering the use of single coil pickups. Dialing up the breath processor did introduce a slight increase, but not too invasive. The expander section took some getting used to, however – a very sensitive control. When long sustained notes would fade in volume past the threshold dB setting it would cause the expander to chatter a bit. In soft passages or song ends this would have to be reckoned with. The compressor section did a nice job of controlling quick slap bass transients on a rendition of Sly Stone’s “Thank You Fa Lettin’ Me Be Myself,” and the breath control gave a nice, wiry presence to the strings. The auto switch enables a good, program dependent setting for attack and release parameters, but if you want to go a little over the top you’ll have to go manual.

On vocals, I used a Shure Beta 58 through the Mackie. The expander worked much better in this setting, shutting off background noise effortlessly between passages, although mic handling noise gave it some trouble. On a stand this wouldn’t be a problem. The breath control added some nice air, except on sibilants, but judicious use produced a nice effect.

In a live setting with a local rock band I patched the CPL2 into the buss insert for the drums with good results, taming an otherwise skull shattering 6.5-inch x 14-inch chrome Ludwig snare and 26-inch bass drum (the guy likes Bonham).

From a fit and finish standpoint, the CPL2 is solid, with nice easy to read graphics on a silver powdercoat chassis. I also appreciate the IEC power cord, as opposed to those infernal wallwarts. This also means the unit had to pass NRTL (Nationally Recognized Test Lab) testing with an internal power supply, as evidenced by the ETL logo. The unit has a high 50 kohm input impedance and low 60 ohm output impedance, which should easily enable good impedance matching with most other brands of pro audio equipment.

I liked the Crate CPL2 stereo compressor; it has all the basic functions needed in a dynamics processor, with a couple of useful additions. And while it probably won’t be found in a mastering lab, at a list price under $170 dollars, it is a good means to entice the MI crowd into embracing dynamics control.